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All You Never Really Wanted to Know About Hepatitis A

What is Hepatitis A?

Hepatitis A is one of five human hepatitis viruses (hepatitis A, B, C, D, and E) that primarily infect the liver and cause illness. An estimated 80,000 cases occur each year in the U.S., although much higher estimates have been proposed based on mathematical modeling of the past incidence of infection. Each year, an estimated 100 persons die as a result of acute liver failure in the U.S. due to hepatitis A, but the rate of infection has dramatically decreased since the hepatitis A vaccine was licensed and became available in the U.S. in 1995.

Hepatitis A is a communicable (or contagious) disease that spreads from person-to-person. It is spread almost exclusively through fecal-oral contact, generally from person-to-person, or via contaminated food or water. Food contaminated with the virus is the most common vehicle transmitting hepatitis A. The food preparer or cook is the individual most often contaminating the food, although he or she is generally not ill at the time of food preparation. The peak time of infectivity, when the most virus is present in the stool of an infectious individual, is during the two weeks before illness begins. Although only a small percentage of hepatitis A infections are associated with foodborne transmission, foodborne outbreaks have been increasingly implicated as a significant source of hepatitis A infection.

Hepatitis A may also be spread by household contact among families or roommates, sexual contact, ingestion of contaminated water, ingestion of raw or undercooked fruits and vegetables or shellfish (like oysters), and from persons sharing illicit drugs. Children often have asymptomatic or unrecognized infections and can pass the virus through ordinary play to family members and other children and adults.

Symptoms of Hepatitis A Infection

Hepatitis A infection may cause no symptoms at all when it is contracted, especially in children. Such individuals will only know they were infected (and have become immune ñ you can only get hepatitis A once) by getting a blood test later in life. The incubation period (from exposure to onset of symptoms) is 15-50 days, with an average of 30 days. Many children and most adults will experience the sudden onset of flu-like symptoms. After a day or two of muscle aches, headache, anorexia (loss of appetite), abdominal discomfort, fever and malaise, jaundice (also termed icterus) sets in. Jaundice is a yellowing of the skin, eyes and mucous membranes that occurs because bile flows poorly through the liver and backs up into the blood. The urine will turn dark with bile and the stool will be light or clay-colored from lack of bile. When jaundice sets in, the initial symptoms begin to subside.

In general, the period of acute illness lasts from 10 days to three weeks, at which time affected individuals tend to recapture some sense of wellness. It is not unusual for blood tests to remain abnormal for six months (or more), prolonging recovery for up to a year. Most affected individuals show complete recovery within three to six months of the onset of illness. Relapse is possible, and although more common in children, it does occur with some regularity in adults.

Diagnosis and treatment of Hepatitis A

There are blood tests widely available to accurately diagnose hepatitis A; blood samples are tested for hepatitis antibodies, which are present when the immune system responds to the hepatitis virus. Antibodies of the immune globulin (Ig) M variety, which indicate acute disease, and IgG antibodies, which stay positive for life, should both be measured.

Hepatitis A infection is an acute self-limiting disease. There is no specific treatment; treatment and management is merely supportive. The liver function tests generally improve as the affected individual begins to feel better. It is therefore well accepted that the need for rest is best determined by the person’s own perception of the severity of fatigue or malaise.

Preventing Hepatitis A Infection

Hepatitis A infection is totally preventable. Ill food-handlers should be excluded from work. Commercial food workers and other individuals who prepare food for others must always wash their hands with soap and water after using the bathroom, changing a diaper, and before preparing food. Cooking food to a temperature of 185∞F or higher will inactivate hepatitis A.

After a known exposure to hepatitis A, administration of a shot of immune globulin should be considered. If administered within two weeks of the exposure, it will usually be effective in preventing or at least ameliorating the disease.

Hepatitis A vaccine is the best protection from hepatitis A infection. The vaccine is recommended for persons traveling to areas with increased rates of hepatitis A, men who have sex with men, injecting and non-injecting drug users, persons with blood clotting factor disorders (such as hemophilia), persons with chronic liver disease, and children living in regions of the U.S. with increased rates of hepatitis A. The vaccine may also help protect household contacts of those with hepatitis A infection. Vaccination of food handlers would likely substantially diminish the incidence of hepatitis A outbreaks. The vaccine is licensed for individuals aged two and older, but there is good evidence that the vaccine is safe and effective at one year of age.


Advisory Committee on Immunization Practices (ACIP), Fiore AE, Wasley A, Bell BP. (2006). Prevention of hepatitis A through active or passive immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep.55(RR-7):1-23.

Bialek SR, Thoroughman DA, Hu D, Simard EP, Chattin J, Cheek J, Bell BP. (2004). Hepatitis A Incidence and Hepatitis A Vaccination Among American Indians and Alaska Natives, 1990–2001. Am J Public Health. 94(6):996-1001.

Bownds L, Lindekugel R, Stepak P. (2003). Economic impact of a hepatitis A epidemic in a mid-sized urban community: the case of Spokane, Washington. J Community Health. 28(4):233-246.

Butot S, Putallaz T, Sánchez G. (2008). Effects of sanitation, freezing and frozen storage on enteric viruses in berries and herbs. Int J Food Microbiol. 126(1-2):30-35.

Calder L, Simmons G, Thornley C, Taylor P, Pritchard K, Greening G, Bishop J. (2003). An outbreak of hepatitis A associated with consumption of raw blueberries. Epidemiol Infect. 131(1):745-751.

Centers for Disease Control and Prevention (2009a). Disease Burden from Viral Hepatitis A, B, and C in the United States. Available at http://www.cdc.gov/hepatitis/PDFs/disease_burden.pdf).

Centers for Disease Control and Prevention (2009b). Surveillance for Acute Viral Hepatitis—- United States, 2007. Surveillance Summaries. 58 (SS03):1-27.

Centers for Disease Control and Prevention (2009c). Hepatitis A. In: Epidemiology and Prevention of Vaccine-Preventable Diseases. Atkinson W, Wolfe S, Hamborsky J, McIntyre L, eds. 11th ed. Washington DC: Public Health Foundation, pp. 85-97.

Centers for Disease Control and Prevention (2009d). Updated recommendations from the Advisory Committee on Immunization Practices (ACIP) for use of hepatitis A vaccine in close contacts of newly arriving international adoptees. Centers for Disease Control and Prevention (CDC); Advisory Committee on Immunization Practices. MMWR Morb Mortal Wkly Rep. 58(36):1006-7.

CDC (2007). Update: Prevention of Hepatitis A after Exposure to Hepatitis A Virus and in International Travelers. Updated Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR. 56(41);1080-1084.

Detry O, De Roover A, Honore P, Meurisse M. (2006). Brain edema and intracranial hypertension in fulminant hepatic failure: pathophysiology and management. World J Gastroenterol. 12: 7405-7412.

Feldman, M, Friedman, LS, Sleisenger, MH. (2002). Sleisenger and Fordtran’s Gastrointestinal and Liver Disease: Pathophysiology/Diagnosis/Management. 7th ed. [2-volume set]. St. Louis, MO: Saunders. 80: 1571.

Fiore, AE. ( 2004). “Hepatitis A Transmitted by Food.” Clinical Infectious Diseases. 38:705-715.

Gilkson M, Galun E, Oren R, Tur-Kaspa R, Shouval D. (1992). Relapsing hepatitis A. Review of 14 cases and literature survey. Medicine. 71:14-23.

Hutin YJF, Pool V, Cramer EH, et al. (1999). A multistate, foodborne outbreak of hepatitis A. N Engl J Med. 340:595–602.

Jaykus L. (1997). Epidemiology and Detection as Options for Control of Viral and Parasitic Foodborne Disease. Emerg Infect Dis. 3(4):529-539.

Mayo Clinic. (2009). Hepatitis A. Available at http://www.mayoclinic.com/health/hepatitis-a/DS00397.

Piazza M, Safary A, et al. (1999). Safety and immunogenicity of hepatitis A vaccine in infants: a candidate for inclusion in the childhood vaccination program. Vaccine. 17:585-588.

Rawls RA and Vega KJ (2005). Viral Hepatitis in Minority America. J Clin Gastroenterol. 39:144–151.

Sagliocca L, Amoroso P, et al. (1999). Efficacy of hepatitis A vaccine in prevention of secondary hepatitis A infection: A randomized trial. Lancet. 353:1136-39.

Scharff RL, McDowell J, Medeiros L. (2009). Economic Cost of Foodborne Illness in Ohio. J Food Prot. 72(1):128-136.

Schiff ER. (1992). Atypical Manifestations of hepatitis-A. Vaccine. 10(Suppl. Vol. 1): 18-20.

Taylor R, Davern T, Munoz S, Han S-H, McGuire B, Larson AM, et al. (2006). Fulminant hepatitis A virus infection in the United States: incidence, prognosis, and outcomes. Hepatology. 44:1589-1597.

Todd EC, Greig JD, Bartleson CA, Michaels BS. (2009). Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 6. Transmission and survival of pathogens in the food processing and preparation environment. J Food Prot. 72(1):202-219.

Wheeler C, Vogt TM, Armstrong GL, et al. (2005). An Outbreak of Hepatitis A Associated with Green Onions. N Engl J Med. 353: 890-897.

Willner IR, Uhl MD, Howard SC, Williams EQ, Riely CA, Waters B. (1998). Serious hepatitis A: an analysis of patients hospitalized during an urban epidemic in the United States. Ann Intern Med. 128:111-114.

Claravale Farm Link in 2012 Campylobacter Outbreak that Sickened 22

san-francisco-clara-vale-grade-a-raw-milk-img_2975In early February 2012, the California Department of Public Health (CDPH), Food and Drug Branch (FDB) was notified by the CDPH Infectious Diseases Branch (IDB) about a cluster of California residents with Campylobacteriosis. All cases had exposure to raw (unpasteurized) milk. IDB determined that the majority of case patients had consumed Claravale Farms brand raw milk products during the period preceding their illnesses. A total of 22 cases of C. jejuni were reported to IDB over the course of this investigation. The age range of case patients was one to 66 years. Illness onset dates ranged from January 29, 2012 to April 9, 2012. Five Campylobacter isolates collected from cases that had exposure to Claravale Farms raw milk were a genetic match using Pulsed field gel electrophoresis (PFGE). These isolates also matched the PFGE patterns from the Claravale Farms raw cream samples collected by FDB and the California Department of Food and Agriculture (pattern designation DBRS16.0024/DBRK02.1142).

Samples of Claravale Farms raw whole milk were collected from four case patients who still had remaining product. Samples were tested for Campylobacter and Escherichia coli O157:H7. Campylobacter was not detected in any of the raw milk samples, however, two unopened bottles of raw whole milk tested positive for E. coli O157:H7. FDB initiated an environmental investigation at the dairy based on the positive findings.

On March 13 and 14, 2012, FDB investigators collected a total of 170 samples at Claravale Farms: 22 product (whole raw cow milk, nonfat raw cow milk, raw cow cream, and raw goat milk), 62 sponge swabs, 11 soil, 17 water, and 58 feces. Of the 22 product samples, one (raw cow cream) was positive for C. jejuni, and two (one whole and one nonfat raw cow milk) were positive for non-O157:H7 E. coli. The California Department of Food and Agriculture (CDFA) also was on-site and collected product samples from the dairy which were tested for standard plate count, coliforms, Campylobacter, Salmonella, E. coli O157:H7, and Listeria. One sample, raw cow cream, was positive for C. jejuni. This finding prompted CDFA to issue a statewide recall and quarantine order to Claravale Farms on March 23, 2012. This order prevented the dairy from selling all raw milk products, and necessitated the removal of their raw cow milk, raw non-fat cow milk, raw cow cream, and raw goat milk from retail locations. Claravale Farms had already ceased distribution on March 19, 2012 due to their knowledge of CDFA’s presumptive positive result of the raw cow cream sample. The firm ceased operations until the quarantine was lifted on March 29, 2012.

FDB and CDFA returned to Claravale Farms on April 23, 2012 due to additional Campylobacteriosis cases associated with raw milk from Claravale Farms subsequent to the CDFA quarantine release. Thirty one additional environmental samples were collected by FDB. C. jejuni was detected in one sample collected from a floor drain in the clean-in-place room. This sample did not match the outbreak strain.

CDPH’s environmental and epidemiological investigation indicated that raw whole cow milk manufactured by Claravale Farms was likely contaminated with C. jejuni that led to illness. Operational deficiencies were reported which could have contributed to contamination of the raw milk.


Blue Bell Ice Cream Listeria Outbreak – Epidemiological, Labratory and Environmental Facts

  • Four rare strains of Listeria monocytogenes in five patients in Kansas hospital with onset dates January 2014 to January 2015.
  • Invoices link hospital purchases to Blue Bell Creameries in Brenham, Texas.
  • Three strains of Listeria monocytogenes isolated from the ice cream samples linked by samples taken in South Carolina.
  • Texas Department of State Health Services found Listeria monocytogenes on products made on same product line at Blue Bell’s facility.

Outbreak+investigation+figure+1According to the CDC and the Kansas Department of Health and Environment, five patients who were treated in a single hospital in Kansas were infected with one of four rare strains of Listeria monocytogenes. All five case patients are adults. Three deaths have been reported. Three of these strains, which are highly similar, have also been found in products manufactured at the Blue Bell Creameries production facility in Brenham, Texas. Illness onset dates range from January 2014 to January 2015.

Three strains of Listeria monocytogenes isolated from the ice cream samples had PFGE patterns that were indistinguishable from those of Listeria bacteria obtained from samples from four patients. Listeria monocytogenes isolates with four other PFGE patterns were also isolated from the ice cream samples. Invoices provided by the hospital to the Kansas Department of Health and Environment indicate that the Blue Bell brand ice cream Scoops used in the patients’ milkshakes came from Blue Bell Creamery’s facility in Texas. Whole genome sequencing of the Listeria monocytogenes isolates obtained from the ice cream is in progress.

FDA was notified that these three strains and four other rare strains of Listeria monocytogenes were found in samples of Blue Bell Creameries single serving Chocolate Chip Country Cookie Sandwich and the Great Divide Bar ice cream products collected by the South Carolina Department of Health & Environmental Control during routine product sampling at a South Carolina distribution center, on February 12, 2015. These products are manufactured at Blue Bell Creameries’ Brenham facility.

The Texas Department of State Health Services, subsequently, collected product samples from the Blue Bell Creameries Brenham facility. These samples yielded Listeria monocytogenes from the same products tested by South Carolina and a third single-serving ice cream product, Scoops, which is also made on the same production line.

According to the Kansas Department of Health and Environment, hospital records available for four patients show that all were served ice cream from Blue Bell Creameries’ prepackaged, single-serving products and milkshakes made from these products.

Everything You Need To Know About Listeria During An Outbreak

An Introduction to ListeriaListeria (pronounced liss-STEER-ē-uh) is a gram-positive rod-shaped bacterium that can grow under either anaerobic (without oxygen) or aerobic (with oxygen) conditions. [4, 18] Of the six species of Listeria, only L. monocytogenes (pronounced maw-NO-site-aw-JUH-neez) causes disease in humans. [18] These bacteria multiply best at 86-98.6 degrees F (30-37 degrees C), but also multiply better than all other bacteria at refrigerator temperatures, something that allows temperature to be used as a means of differentiating Listeria from other contaminating bacteria. [18]

Called an “opportunistic pathogen,” Listeria is noted to cause an estimated 2,600 cases per year of severe invasive illness. [26] Perhaps not surprisingly then, “foodborne illness caused by Listeria monocytogenes has raised significant public health concern in the United States, Europe, and other areas of the world.” [3] As one noted expert observed, summarizing the history of these bacteria and their significance for public health,

Although L. monocytogenes was recognized as an animal pathogen over 80 years ago, the first outbreak confirming an indirect transmission from animals to humans was reported only in 1983, in Canada’s Maritime provinces. In that outbreak, cabbages, stored in the cold over the winter, were contaminated with Listeria through exposure to infected sheep manure. A subsequent outbreak in California in 1985 confirmed the role of food in disseminating listeriosis. Since then Listeria has been implicated in many outbreaks of food-borne illness, most commonly from exposure to contaminated dairy products and prepared meat products, including turkey and deli meats, pâté, hot dogs and seafood and fish. [4]

Given its widespread presence in the environment and food supply, the ingestion of Listeria has been described as an “exceedingly common occurrence.” [18]

The Incidence of Listeria Infections

Listeria bacteria are found widely in the environment in soil, including in decaying vegetation and water, and may be part of the fecal flora of a large number of mammals, including healthy human adults. [4, 18] According to the FDA, “studies suggest that 1-10% of humans may be intestinal carriers of Listeria.” [14] Another authority notes that the “organism has been isolated from the stool of approximately 5% of healthy adults.” [18] Overall, seasonal trends show a notable peak in total Listeria cases and related-deaths from July through October. [3]

Ingested by mouth, Listeria is among the most virulent foodborne pathogens, with up to 20% of clinical infections resulting in death. [3] These bacteria primarily cause severe illness and death in persons with immature or compromised immune systems. [13, 18] Consequently, most healthy adults can be exposed to Listeria with little to any risk of infection and illness. [4, 11]

A study published in 1995 projected Listeria infection-rates to the U.S. population, suggesting that an estimated 1,965 cases and 481 deaths occurred in 1989 compared with an estimated 1,092 cases and 248 deaths in 1993, a 44% and 48% reduction in illness and death, respectively. [25] In comparison, a USDA study published in 1996 estimated that there had been 1,795-1860 Listeria-related cases in 1993, and 445-510 deaths, with 85-95% of these attributable to the consumption of contaminated food. [28] Listeriosis-related mortality rates decreased annually by 10.7% from 1990 through 1996, and by 4.3% from 1996 through 2005. [3]

Among adults 50 years of age and older, infection rates were estimated to have declined from 16.2 per 1 million in 1989 to 10.2 per 1 million in 1993. [25] Perinatal disease decreased from 17.4 cases per 100,000 births in 1989 to 8.6 cases per 100,000 births in 1993. [25] Neonatal infections are often severe, with a mortality rate of 25-50%. [4]

According to the CDC’s National Center for Zoonotic, Vector-Borne, and Enteric Diseases:

Listeriosis was added to the list of nationally notifiable diseases in 2001. To improve surveillance, the Council of State and Territorial Epidemiologists has recommended that all L. monocytogenes isolates be forwarded to state public health laboratories for subtyping through the National Molecular Subtyping Network for Foodborne Disease Surveillance (PulseNet). All states have regulations requiring health care providers to report cases of listeriosis and public health officials try to interview all persons with listeriosis promptly using a standard questionnaire about high risk foods. In addition, FoodNet conducts active laboratory- and population-based surveillance. [7]

In 2006, public health officials from 48 states reported 1,270 foodborne disease outbreaks, with a confirmed or suspect source in 884 of the outbreaks (70%). [8] Only one of the outbreaks with a confirmed source was attributed to Listeria, with this outbreak involving eleven hospitalizations and one death. [8] The next year, of 17,883 lab-confirmed infections, the CDC attributed 122 to Listeria. [9] In 2009, there were 158 confirmed Listeria infections, representing an incidence-rate of .34 cases for every 100,000 persons in the United States. [10] Such data revealed an incidence-rate of 0.27 cases per 100,000 persons, a decrease of 42% compared with 1996—1998. [10] But, according to CDC’s Technical Information website, it is estimated that there are 1,600 cases of Listeria infection annually in the United States, based on data through 2008. [7]

The 2009 numbers represented a reported 30% decrease in the number of infections compared to the 1996—1998 rates of infection. [10] Although the nature and degree of underreporting is subject to dispute, all agree that the confirmed cases represent just the tip of the iceberg. [6, 13] Indeed, one study estimates the annual incidence rate for Listeria to be around 1,795-1,860 cases per 100,000 persons, with 445-510 of the cases ending in death. [28]

Finally, in a study of FoodNet laboratory-confirmed invasive cases—where infection is detected in blood, cerebrospinal fluid, amniotic fluid, placenta or products of conception—the number of listeriosis cases decreased by 24% from 1996 through 2003. [33] During this same period, pregnancy-associated disease decreased by 37%, while cases among those fifty years old and older decreased by 23%. [33]

The Prevalence of Listeria in Food and the Environment

Listeria is a common presence in nature, found widely in such places as water, soil, infected animals, human and animal feces, raw and treated sewage, leafy vegetables, effluent from poultry and meat processing facilities, decaying corn and soybeans, improperly fermented silage, and raw (unpasteurized) milk. [18, 23, 27]  Foods commonly identified as sources of Listeria infection include  improperly pasteurized fluid milk, cheeses (particularly soft-ripened varieties, such as traditional Mexican cheeses, Camembert and ricotta), ice cream, raw vegetables, fermented raw-meat sausages, raw and cooked poultry, and cooked, ready-to-eat (RTE) sliced meats—often referred to as “deli meats”. [18, 21, 23, 28] One study found that, over a five-year period of testing, in multiple processing facilities, Listeria monocytogenes was isolated from 14% of 1,080 samples of smoked finfish and smoked shellfish. [16]

Ready-to-eats foods have been found to be a notable and consistent source of Listeria. [14, 21] For example, a research-study done by the Listeria Study Group found that Listeria monocytogenes grew from at least one food specimen in the refrigerators of  64% of persons with a confirmed Listeria infection (79 of 123 patients), and in 11% of more than 2000 food specimens collected in the study. [21] Moreover, 33% of refrigerators (26 of 79) contained foods that grew the same strain with which the individual had been infected, a frequency much higher than would be expected by chance. [21] A widely cited USDA study that reviewed the available literature also summarized that:

In samples of uncooked meat and poultry from seven countries, up to 70 percent had detectable levels of Listeria [13].  Schuchat [23] found that 32 percent of the 165 culture-confirmed listeriosis cases could be attributed to eating food purchased from store delicatessen counters or soft cheeses.  In Pinner [21] microbiologic survey of refrigerated foods specimens obtained from households with listeriosis patients, 36 percent of the beef samples and 31 percent of the poultry samples were contaminated with Listeria.

The prevalence of Listeria in ready-to-eat meats has not proven difficult to explain. [26, 29] As one expert in another much-cited article has noted:

The centralized production of prepared ready-to-eat food products…increases the risk of higher levels of contamination, since it requires that foods be stored for long periods at refrigerated temperatures that favour the growth of Listeria. During the preparation, transportation and storage of prepared foods, the organism can multiply to reach a threshold needed to cause infection. [4]

The danger posed by the risk of Listeria in ready-to-eat meats has prompted the USDA to declare the bacterium an adulterant in these kinds of meat products and, as a result, to adopt a zero-tolerance policy for the presence of this deadly pathogen. [7, 29]

A USDA Baseline Data Collection Program done in 1994 documented Listeria contamination on 15.0% of broiler-chicken carcasses [30]. Subsequent USDA data-collection did not test for the prevalence of Listeria in chicken or in turkeys. [31, 32]

Transmission and Infection

Except for the transmission of mother to fetus, human-to-human transmission of Listeria is not known to occur. [18] Infection is caused almost exclusively by the ingestion of the bacteria, most often through the consumption of contaminated food. [18, 21, 23] The most widely-accepted estimate of foodborne transmission is 85-95% of all Listeria cases. [23, 28]

The infective dose—that is, the amount of bacteria that must be ingested to cause illness—is not known. [4, 18, 26] In an otherwise healthy person, an extremely large number of Listeria bacteria must be ingested to cause illness—estimated to be somewhere between 10–100 million viable bacteria (or colony forming units “CFU”) in healthy individuals, and only 0.1–10 million CFU in people at high risk of infection. [4, 18, 26] Even with such a dose, a healthy individual will suffer only a fever, diarrhea, and related gastrointestinal symptoms. [4, 18].

The amount of time from infection to the onset of symptoms—typically referred to as the incubation period—can vary to a significant degree.  Symptoms of Listeria infection can develop at any time from 2 to 70 days after eating contaminated food. [4, 5] According to one authoritative text,

The incubation period for invasive illness is not well established, but evidence from a few cases related to specific ingestions points to 11 to 70 days, with a mean of 31 days. In one report, two pregnant women whose only common exposure was attendance at a party developed Listeria bacteremia with the same uncommon enzyme type; incubation periods for illness were 19 and 23 days. [18]

Adults can get listeriosis by eating food contaminated with Listeria, but babies can be born with listeriosis if their mothers eat contaminated food during pregnancy. [4, 24] The mode of transmission of Listeria to the fetus is either transplacental via the maternal blood stream or ascending from a colonized genital tract. [24] Infections during pregnancy can cause premature delivery, miscarriage, stillbirth, or serious health problems for the newborn. [18, 24]

Incidence of Listeria infection in HIV-positive individuals is higher than in the general population. [17, 18] One study found that:

The estimated incidence of listeriosis among HIV-infected patients in metropolitan Atlanta was 52 cases per 100,000 patients per year, and among patients with AIDS it was 115 cases per 100,000 patients per year, rates 65–145 times higher than those among the general population. HIV-associated cases occurred in adults who were 29–62 years of age and in postnatal infants who were 2 and 6 months of age. [17]

Pregnant women make up around 30% of all infection cases, while accounting for 60% of cases involving the 10- to 40-year age group. [18]

Those Most Susceptible to Infection

Several segments of the population are at increased risk and need to be informed so that proper precautions can be taken. [19,20, 27] The body’s defense against Listeria is called “cell-mediated immunity” because the success of defending against infection depends on our cells (as opposed to our antibodies), especially lymphocytes called “T-cells.” [12] Therefore, individuals whose cell-mediated immunity is suppressed are more susceptible to the devastating effects of listeriosis, including especially HIV-infected individuals, who have been found to have a Listeria-related mortality of 29%. [12, 17, 18]

Pregnant women naturally have a depressed cell-mediated immune system. [18, 24] In addition, the immune systems of fetuses and newborns are very immature and are extremely susceptible to these types of infections. [24] Other adults, especially transplant recipients and lymphoma patients, are given necessary therapies with the specific intent of depressing T-cells, and these individuals become especially susceptible to Listeria as well. [7, 18, 27]

According to the CDC and other public health organizations, individuals at increased risk for being infected and becoming seriously ill with Listeria include the following groups:

  • Pregnant women: They are about 20 times more likely than other healthy adults to get listeriosis. About one-third of listeriosis cases happen during pregnancy.
  • Newborns: Newborns rather than the pregnant women themselves suffer the serious effects of infection in pregnancy.
  • Persons with weakened immune systems
  • Persons with cancer, diabetes, or kidney disease
  • Persons with AIDS: They are almost 300 times more likely to get listeriosis than people with normal immune systems.
  • Persons who take glucocorticosteroid medications (such as cortisone)
  • The elderly [11, 20, 21]

Symptoms of Listeria infection

When a person is infected and develops symptoms of Listeria infection, the resulting illness is called listeriosis. [4, 11, 18] Only a small percentage of persons who ingest Listeria fall ill or develop symptoms. [18] For those who do develop symptoms as a result of their infection, the resulting illness is either mild or quite severe—sometimes referred to as a “bimodal distribution of severity.” [13, 28]

On the mild end of the spectrum, listeriosis usually consists of the sudden onset of fever, chills, severe headache, vomiting, and other influenza-type symptoms. [18, 28]  Along these same lines, the CDC notes that infected individuals may develop fever, muscle aches, and sometimes gastrointestinal symptoms such as nausea or diarrhea. [11] When present, the diarrhea usually lasts 1-4 days (with 42 hours being average), with 12 bowel movements per day at its worst. [18]

Most healthy adults and children who consume contaminated food experience only mild to moderate symptoms. The infection is usually self-limited, since, in healthy hosts, exposure to Listeria stimulates the production of tumour necrosis factor and other cytokines, which activate monocytes and macrophages to eradicate the organism.  Few people with normal immune function go on to have more severe, life-threatening forms of listeriosis, characterized by septic shock, meningitis and encephalitis. [4]

As already noted, when pregnant, women have a mildly impaired immune system that makes them susceptible to Listeria infection. [19] If infected, the illness appears as an acute fever, muscle pain, backache, and headache. [18, 24] Illness usually occurs in the third trimester, which is when immunity is at its lowest. [18] Infection during pregnancy can lead to premature labor, miscarriage, infection of the newborn, or even stillbirth. [24, 28] Twenty-two percent of such infections result in stillbirth or neonatal death. [18]

Newborns may present clinically with early-onset (less than 7 days) or late-onset forms of infection (7 or more days). [3] Those with the early-onset form are often diagnosed in the first 24 hours of life with sepsis (infection in the blood). [3, 18] Early-onset listeriosis is most often acquired through trans-placental transmission. [18, 24] Late-onset neonatal listeriosis is less common than the early-onset form. [4, 18, 24] Clinical symptoms may be subtle and include irritability, fever and poor feeding. [24] The mode of acquisition of late-onset listeriosis is poorly understood. [18, 24]

Diagnosis and Treatment of Listeria Infections

Because there are few symtpoms that are unique to listeriosis, doctors must consider a variety of potential causes for infection, including viral infections (like flu), and other bacterial infections that may cause sepsis or meningitis. [4, 18, 19]

Early diagnosis and treatment of listeriosis in high-risk patients is critical, since the outcome of untreated infection can be devastating. This is especially true for pregnant women because of the increased risk of spontaneous abortion and preterm delivery. Depending on the risk group, rates of death from listeriosis range from 10% to 50%, with the highest rate among newborns in the first week of life. [4]

Methods typically used to identify diarrhea-causing bacteria in stool cultures interfere or limit the growth of Listeria, making it less likely to be identified and isolated for further testing. [18] On the other hand, routine methods are effective for isolating Listeria from spinal fluid, blood, and joint fluid. [4, 18] Magnetic-resonance imaging (MRI) is used to confirm or rule out brain or brain stem involvement. [18]

Listeriosis is usually a self-limited illness—which means that a majority of infected individuals will improve without the need for medical care. [4, 11, 14, 18] But for those patients with a high fever, a stool culture and antibiotic-treatment may be justified for otherwise healthy individuals. [4, 18] Although there have been no studies done to determine what drugs or treatment duration is best, ampicillin is generally considered the “preferred agent.” [18] There is no consensus on the best approach for patients who are allergic to penicillins.[18]

Invasive infections with Listeria can be treated with antibiotics. [18] When infection occurs during pregnancy, antibiotics given promptly to the pregnant woman can often prevent infection of the fetus or newborn. [18, 24] Babies with listeriosis receive the same antibiotics as adults, although a combination of antibiotics is often used until physicians are certain of the diagnosis.

Complications of Listeria infection

For those persons who suffer a Listeria infection that does not resolve on its own, the complications (or sequelae) can be many. [4, 28] The most common is septicemia (bacterial pathogens in the blood, also known as bacteremia), with meningitis being the second most common. [4, 18] Other complications can include inflammation of the brain or brain stem (encephalitis), brain abscess, inflammation of the heart-membrane (endocarditis), and localized infection, either internally or of the skin. [18]

Death is the most severe consequence of listeriosis, and it is tragically common. [3] For example, based on 2009 FoodNet surveillance data, 89.2% of Listeria patients ended up in the hospital, the highest hospitalization rate for pathogenic bacterial infection. [10] In persons 50 years of age and older, there was a 17.5% fatality rate—also the highest relative to other pathogens. [10, 18]

The Economic Impact of Listeria Infections

The USDA Economic Research Service (ERS) published its first comprehensive cost estimates for sixteen foodborne bacterial pathogens in 1989. [22]  Five years later, it was estimated that, in 1993, there were 1,795 to 1,860 Listeria infections that required hospitalization, with 295-360 of these cases involving pregnant women. [28]  Based on these estimates, the medical costs that Listeria infections had caused each year were said to run from $61.7 to $64.8 million, including those individuals who ultimately died as a result of their infections. [28] For these same acute cases, productivity costs were estimated to run from $125.8 to $154.4 million a year. [28] The productivity costs associated with Listeria-related chronic illness was estimated to be an additional $38 million a year. [28] In sum, “[e]stimates of total costs for the 1,795 to 1,860 cases of listeriosis range from $232.7 million to $264.4 million annually.” [28]

In 2000, USDA updated the cost-estimates for four pathogens:  Campylobacter, Salmonella, E. coli O157:H7, and Listeria monocytogenes. [28a] The 2000 estimates were based on the CDC’s then newly-released estimates of annual foodborne illnesses, and put the total cost in the United States for these four pathogens at $6.5 billion a year. [28a] For Listeria specifically, it was estimated that costs amounted to $2.3 billion per year, based on 2,493 cases, which involved 2,298 hospitalizations and 499 deaths. [28a]  More recently, in 2007, it was estimated that the worldwide cost of all foodborne disease was $1.4 trillion per year. [6]

Real Life Impacts of Listeria Infection

Because Listeria infection is most severe in elderly persons, pregnant women and newborns, the symptoms of infection vary greatly.

  • In older adults or immunocompromised individuals, septicemia (Listeria bacteria in the blood stream) and meningitis are the most common indicators of illness.
  • In pregnant women, a mild, flu-like illness can be followed by miscarriage, premature delivery or stillbirth.
  • In newborns, bacteremia (Listeria bacteria in the blood stream) and meningitis are the most common indicators of Listeria infection.

Antimicrobial Resistance in Bacteria

Antimicrobial resistance in bacteria is an emerging and increasing threat to human health. [1, 4] Physicians are increasingly aware that antimicrobial resistance is increasing in foodborne pathogens and that, as a result, patients who are prescribed antibiotics are at increased risk for acquiring antimicrobial-resistant foodborne infections. [1] Indeed, “increased frequency of treatment failures for acute illness and increased severity of infection may be manifested by prolonged duration of illness, increased frequency of bloodstream infections, increased hospitalization or increased mortality.” [3]

The use of antimicrobial agents in the feed of food animals is estimated by the FDA to be over 100 million pounds per year. [4]  It is estimated that 36% to 70% of all antibiotics produced in the United States are used in a food animal feed or in prophylactic treatment to prevent animal disease. [3, 4, 18] In 2002, the Minnesota Medical Association published an article by David Wallinga, M.D., M.P.H. who wrote:

According to the [Union of Concerned Scientists], 70 percent of all the antimicrobials used in the United States for all purposes—or about 24.6 million pounds annually—are fed to poultry, swine, and beef cattle for nontherapeutic purposes, in the absence of disease. Over half are “medically important” antimicrobials; identical or so closely related to human medicines that resistance to the animal drug can confer resistance to the similar human drug. Penicillin, tetracycline, macrolides, streptogramins, and sulfonamides are prominent examples. [33]

The use of antibiotics in feed for food animals, on animals prophylactically to prevent disease, and the use of antibiotics in humans unnecessarily must be reduced. [1, 25] European countries have reduced the use of antibiotics in animal feed and have seen a corresponding reduction in antibiotic-resistant illnesses in humans. [1, 4]

The Prevention of Listeria infection

Given its widespread presence in the environment, and the fact that the vast majority of Listeria infections are the result of consuming contaminated food or water, preventing illness and death is necessarily (and understandably) a food safety issue.

L. monocytogenes presents a particular concern with respect to food handling because it can grow at refrigerator temperatures (4°C to 10°C), temperatures commonly used to control pathogens in foods. Freezing also has little detrimental effect on the microbe. Although pasteurization is sufficient to kill Listeria, failure to reach the desired temperature in large packages can allow the organism to survive. Food can also be contaminated after processing by the introduction of unpasteurized material, as happens during the preparation of some cheeses. Listeria can also be spread by contact with contaminated hands, equipment and counter tops. [4]

The use of irradiation to reduce Listeria to safe levels in foods has many proponents. [26] As noted by an eminent CDC researcher, Robert V. Tauxe,

Ready-to-eat meats, such as hot dogs, have already been subjected to a pathogen-killing step when the meat is cooked at the factory, so contamination is typically the result of in-plant contamination after that step. Improved sanitation in many plants has reduced the incidence of infection by half since 1986, but the risk persists, as illustrated by a large hot dog-associated outbreak that occurred in 1999. Additional heat treatment or irradiation of meat after it is packaged would eliminate Listeria that might be present at that point. [26]

The CDC provides a comprehensive list of recommendations and precautions to avoid becoming infected with Listeria, which are as follows:

· Thoroughly cook raw food from animal sources, such as beef, pork, or poultry to a safe internal temperature. For a list of recommended temperatures for meat and poultry, visit http://www.fsis.usda.gov/PDF/IsItDoneYet_Magnet.pdf.

· Rinse raw vegetables thoroughly under running tap water before eating.

· Keep uncooked meats and poultry separate from vegetables and from cooked foods and ready-to-eat foods.

· Do not drink raw (unpasteurized) milk, and do not eat foods that have unpasteurized milk in them.

· Wash hands, knives, countertops, and cutting boards after handling and preparing uncooked foods.

· Consume perishable and ready-to-eat foods as soon as possible.

Recommendations for persons at high risk, such as pregnant women and persons with weakened immune systems, in addition to the recommendations listed above, include:

· Meats

o Do not eat hot dogs, luncheon meats, cold cuts, other deli meats (e.g., bologna), or fermented or dry sausages unless they are heated to an internal temperature of 165°F or until steaming hot just before serving.

o Avoid getting fluid from hot dog and lunch meat packages on other foods, utensils, and food preparation surfaces, and wash hands after handling hot dogs, luncheon meats, and deli meats.

o Do not eat refrigerated pâté or meat spreads from a deli or meat counter or from the refrigerated section of a store. Foods that do not need refrigeration, like canned or shelf-stable pâté and meat spreads, are safe to eat. Refrigerate after opening.

· Cheeses

o Do not eat soft cheese such as feta, queso blanco, queso fresco, brie, Camembert, blue-veined, or panela (queso panela) unless it is labeled as made with pasteurized milk. Make sure the label says, “MADE WITH PASTEURIZED MILK.”

· Seafood

o Do not eat refrigerated smoked seafood, unless it is contained in a cooked dish, such as a casserole, or unless it is a canned or shelf-stable product. Refrigerated smoked seafood, such as salmon, trout, whitefish, cod, tuna, and mackerel, is most often labeled as “nova-style,” “lox,” “kippered,” “smoked,” or “jerky.” These fish are typically found in the refrigerator section or sold at seafood and deli counters of grocery stores and delicatessens. Canned and shelf stable tuna, salmon, and other fish products are safe to eat.

Recommendations to keep food safe:

· Be aware that Listeria monocytogenes can grow in foods in the refrigerator. Use an appliance thermometer, such as a refrigerator thermometer, to check the temperature inside your refrigerator. The refrigerator should be 40°F or lower and the freezer 0°F or lower.

· Clean up all spills in your refrigerator right away–especially juices from hot dog and lunch meat packages, raw meat, and raw poultry.

· Clean the inside walls and shelves of your refrigerator with hot water and liquid soap, then rinse.

· Divide leftovers into shallow containers to promote rapid, even cooling. Cover with airtight lids or enclose in plastic wrap or aluminum foil. Use leftovers within 3 to 4 days.

· Use precooked or ready-to-eat food as soon as you can. Do not store the product in the refrigerator beyond the use-by date; follow USDA refrigerator storage time guidelines:

o Hot Dogs – store opened packages no longer than 1 week and unopened packages no longer than 2 weeks in the refrigerator.

o Luncheon and Deli Meat – store factory-sealed, unopened packages no longer than 2 weeks. Store opened packages and meat sliced at a local deli no longer than 3 to 5 days in the refrigerator. [11]

Additional preventive steps and precautions can be found on the websites of most State Departments of Health, including, for example, the Minnesota Department of Health. [20] There is also excellent information to be found at the Extension Service website of the Institute of Food and Agricultural Sciences at University of Florida. [27]


  1. Angulo, F.J., et al., “Antimicrobial Use in Agriculture: Controlling the Transfer of Antimicrobial Resistance to Humans,” SEMINARS IN PEDIATRIC INFECTIOUS DISEASES, Vol. 15, No. 2, pp. 78-85 (April 2004).
  2. Angulo, F.J., et al., “Evidence of an Association Between Use of Anti-microbial Agents in Food Animals and Anti-microbial Resistance Among Bacteria Isolated from Humans and the Human Health Consequences of Such Resistance, JOURNAL OF VETERINARY MEDICINE, Series-B, Vol. 51, Issue 8-9, pp. 374-79 (Oct. 2004).
  3. Bennion, J.R., et al., “Decreasing Listeriosis Mortality in the United States, 1990-2005,” CLINICAL INFECTIOUS DISEASES, Vol. 47, No. 7, pp. 867-74 (2008), available online at http://cid.oxfordjournals.org/content/47/7/867.long
  4. Bortolussi, R, “Listeriosis: A Primer,” CANADIAN MEDICAL ASSOCIAION JOURNAL, Vol. 179, No. 8, pp. 795-7 (Oct. 7, 2008), online at http://www.cmaj.ca/content/179/8/795.long
  5. Bryan, Frank, “Procedures to Investigate Foodborne Illness,” International Association for Food Protection, p. 119 (5th ed. 1999).
  6. Buzby, Jean and Roberts, Tonya, “The Economics of Enteric Infections: Human Foodborne Disease Costs, GASTROENTEROLOGY, Vol. 136, No. 6, pp. 1851-62 (May 2009).
  7. CDC, National Center for Zoonotic, Vector-Borne, and Enteric Diseases, “Listeriosis—Technical Information,” (last updated: April 6, 2011), available online at http://www.cdc.gov/nczved/divisions/dfbmd/diseases/listeriosis/technical.html
  8. CDC, “Surveillance for Foodborne Disease Outbreaks—United States, 2006,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 58, No. 22, pp. 609-15 (June 12, 2007) at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5822a1.htm
  9. CDC, “Preliminary FoodNet Data on the Incidence of Infection with Pathogens Transmitted Commonly through Food—10 States, 2007,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 57, No. 14, pp. 366-70 (April 11, 2008), available online at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5714a2.htm
  10. CDC, “Preliminary FoodNet Data on the Incidence of Infection with Pathogens Transmitted Commonly through Food—10 States, 2009,” MORBIDITY AND MORTALITY WEEKLY REPORT, Vol. 59, No. 14, pp. 418-22 (April 16, 2010) available online at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5914a2.htm
  11. CDC, National Center for Zoonotic, Vector-Borne, and Enteric Diseases, “Listeriosis—General Information and Frequently Asked Questions,” (last updated: April 6, 2011), available at http://www.cdc.gov/nczved/divisions/dfbmd/diseases/listeriosis/
  12. Cossart, P. and Bierne, H., “The Use f Host Cell Machinery in the Pathogenesis of Listeria monocytogenes,” CURRENT OPINIONS IN IMMUNOLOGY, Vol. 13, No. 1, pp. 96-103 (Feb. 2001).
  13. Council for Agriculture, Science and Technology (CAST), “Foodborne Pathogens: Risks and Consequences: Task Force Report No.122,” pp. 1-87 (Sept. 1994) download at http://www.cast-science.org/publications/index.cfm/foodborne_pathogens_risks_and_consequences?show=product&productID=2852
  14. FDA, “Bad Bug Book: Foodborne Pathogenic Microorganisms and Natural Toxins Handbook—Listeria monocytogenes,” at http://www.cfsan.fda.gov/~mow/chap6.html (site last updated: June 18, 2009).
  15. FDA, Public Meeting, “Listeria monocytogenes Risk Assessment and Risk Management: December 4, 2003 Meeting,” Meeting Agenda and Presentations, available online at http://www.fda.gov/Food/ScienceResearch/ResearchAreas/RiskAssessmentSafetyAssessment/ucm209515.htm For Notice of Public Meeting, see 68 Fed. Reg., Vol. 68, No. 216, at 63108-09, online at http://www.fda.gov/OHRMS/DOCKETS/98fr/03-28045.pdf
  16. Heinitz, M.L. and Johnson, J.M., “The incidence of Listeria spp., Salmonella spp., and Clostridium botulinum in Smoked Fish and Shellfish,” Journal of Food Protection, Vol. 61, pp. 318-23 (March 1998).
  17. Jurado, R.L., et al., “Increased Risk of Meningitis and Bacteremia Due to Listeria monocytogenes in Patients with Human Immunodeficiency Virus Infection,” Clinical Infectious Diseases, Vol. 17, No. 2, pp. 224-7 (1993).
  18. Lorber, Bennett, “Listeria monocytogenes,” in Mandell, Douglas, And Bennett’s PRINCIPLES AND PRACTICE OF INFECTIOUS DISEASES, Fifth Edition, Chap. 195, pp. 2208-14 (2000, Mandell, Bennett, and Dolan, Editors).
  19. Mayo Clinic.  (2009). Listeria infection (listeriosis). Retrieved November 1, 2009 from Mayo Clinic website:  http://www.mayoclinic.com/health/Listeria-infection/DS00963.
  20. Minnesota Department of Health (MDH), “Preventing Listeriosis,” available online at http://www.health.state.mn.us/divs/idepc/diseases/listeriosis/prevention.html
  21. Pinner, R.W., et al., “Role of Foods in Sporadic Listeriosis. II. Microbiologic and epidemiologic investigation, JOURNAL OF AMERICAN MEDICAL ASSOCIATION, Vol. 267, No. 15, pp. 2046-50 (April 15, 1992).
  22. Roberts, T, “Human Illness Costs of Foodborne Bacteria,” AMERICAN JOURNAL OF AGRICULTURE ECONOMICS, Vol. 71, No. 2, pp. 468-474 (1989).
  23. Schuchat, A, et al., “Role of Foods in Sporadic Listeriosis. I. Case-control Study of Dietary Risk Factors,” JOURNAL OF AMERICAN MEDICAL ASSOCIATION, Vol. 267, No. 15, pp. 2041-5 (April 15, 1992).
  24. Silver, HM, “Listeriosis during pregnancy,” OBSTETRICAL AND GYNECOLOGICAL SURVEY, Vol. 53, Issue 12, pp. 737-740 (Dec. 1998).
  25. Tappero, JW, et al., “Reduction in the Incidence of Human Listeriosis in the United States: Effectiveness of Prevention Efforts,” JOURNAL OF AMERICAN MEDICAL ASSOCIATION, Vol.  273, No. 14, pp. 1118-22 (April 12, 1995).
  26. Tauxe, Robert, CDC, “Food Safety and Irradiation: Protecting the Public from Foodborne Infections,” EMERGING INFECTIOUS DISEASES, Vol. 7, No. 3, pp. 516-21 (June 2001) at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2631852/pdf/11485644.pdf
  27. University of Florida, IFIS Extension, “Preventing Foodborne Illness: Listeriosis,” Food Science and Human Nutrition Department, Florida Cooperative Extension Service, (Jan. 2003) online at http://edis.ifas.ufl.edu/fs102
  28. USDA Economic Research Service, “Bacterial Foodborne Disease—Medical Costs and Productivity Losses,” AER-741, August 1996 (authors: Jean C. Buzby, et al.) online athttp://www.ers.usda.gov/Publications/AER741/  28a. USDA Economic Research Service, S. Crutchfield and T. Roberts, “Food Safety Efforts Accelerate in the 90’s,” FOOD REVIEW, Vol. 23, No. 3, pp. 44-49 (Sept.-Dec. 2000), online at http://www.ers.usda.gov/publications/foodreview/septdec00/FRsept00h.pdf
  29. USDA Food Safety and Inspection Service (FSIS), “Assessing the Effectiveness of theListeria monocytogenes Interim Final Rule, Summary Report,” (Sept. 28, 2004), available online at http://www.fsis.usda.gov/Oppde/rdad/frpubs/97-013F/LM_Assessment_Report_2004.pdf
  30. USDA FSIS, NATIONWIDE BROILER CHICKEN MICROBIOLOGICAL BASELINE DATA COLLECTION PROGRAM, July 1994—July 1995, (April 1996), full report available online at http://www.fsis.usda.gov/OPHS/baseline/broiler1.pdf
  31. USDA FSIS, THE NATIONWIDE MICROBIOLOGICAL BASELINE DATA COLLECTION PROGRAM: YOUNG CHICKEN SURVEY, July 2007—June 2008, full report available online at http://www.fsis.usda.gov/PDF/Baseline_Data_Young_Chicken_2007-2008.pdf
  32. USDA FSIS, THE NATIONWIDE MICROBIOLOGICAL BASELINE DATA COLLECTION PROGRAM: YOUNG TURKEY SURVEY, Aug. 2008—July 2009, at http://www.fsis.usda.gov/PDF/Baseline_Data_Young_Turkey_2008-2009.pdf
  33. Voetsch, AC, et al., “Reduction in the Incidence of Invasive Listeriosis in Foodborne Diseases Active Surveillance Network Sites, 1996-2003,” CLINICAL INFECTIOUS DISEASES, Vol. 44, No. 4, pp. 513-20 (CDC Control & Prevention Emerging Infections Program, Foodborne Diseases Active Surveillance Network Working Group 2007).
  34. Wallinga, D, “Antimicrobial Use in Animal Feed:  An Ecological and Public Health Problem,” MINNESOTA MEDICINE, Vol. 85, No. 10 pp. 12-16 (Oct. 2002).

Marler Clark, The Food Safety Law Firm, is the nation’s leading law firm representing victims of Listeria outbreaks. The Listeria lawyers of Marler Clark have represented thousands of victims of Listeria and other foodborne illness outbreaks and have recovered over $600 million for clients. Marler Clark is the only law firm in the nation with a practice focused exclusively on foodborne illness litigation. Our Listeria lawyers have litigated Listeria cases stemming from outbreaks traced to a variety of foods, such as caramel apples, cantaloupe, cheese, celery and milk.

CDC: Outbreak of Listeria Linked to Blue Bell Creameries Ice Cream Products

ice-cream-450pxState and local health officials, CDC, and the U.S. Food and Drug Administration (FDA) are collaborating to investigate an outbreak of Listeria monocytogenes infections (listeriosis) likely linked to certain Blue Bell brand ice cream products.

Listeriosis is a life-threatening infection caused by eating food contaminated with the bacterium (germ) Listeria monocytogenes.

Five people infected with one of four strains of Listeria monocytogenes were reported from Kansas.

All five people were hospitalized at the same hospital for unrelated problems before developing invasive listeriosis—a finding that strongly suggests their infections were acquired in the hospital.

Three deaths were reported among these five patients.

Of the four ill people for whom information is available on the foods eaten in the month before Listeria infection, all four consumed milkshakes made with a single-serving Blue Bell brand ice cream product called “Scoops” while they were in the hospital.

Three strains of Listeria monocytogenes isolated from Blue Bell brand ice cream products obtained in 2015 in South Carolina and Texas had pulsed-field gel electrophoresis (PFGE) patterns that were indistinguishable from those of Listeria monocytogenes isolates obtained from samples from four patients.

The Blue Bell brand ice cream products with tests showing Listeria monocytogenes were ice cream Scoops, Chocolate Chip Country Cookie Sandwiches, and Great Divide Bars.

Blue Bell Creameries reported that these products were removed from the market in March 2015. However, contaminated ice cream products may still be in the freezers of consumers, institutions, and retailers.

CDC recommends that consumers do not eat any products that Blue Bell brand ice cream removed from the market. A detailed list of products is available on the Advice page.

This investigation is ongoing, and new information will be provided as it becomes available.

Marler Clark, The Food Safety Law Firm, is the nation’s leading law firm representing victims of Listeria outbreaks. The Listeria lawyers of Marler Clark have represented thousands of victims of Listeria and other foodborne illness outbreaks and have recovered over $600 million for clients. Marler Clark is the only law firm in the nation with a practice focused exclusively on foodborne illness litigation. Our Listeria lawyers have litigated Listeria cases stemming from outbreaks traced to a variety of foods, such as cantaloupe, cheese, celery and milk.

Food Safety For Those Over 60

KATE GUSTMAN RDN, CD, Ridgewood Care Center Dietician

Everyone needs to practice food safety and sanitation. However, for the very young and old the consequences of not doing so are much more detrimental. It is best to follow these guidelines:

  • Practice frequent hand-washing — Wash hands before, during and after cooking, as well as before you eat. Use warm water and soap for 20 seconds, then dry with a clean towel.
  • Keep raw meat and eggs separate — Raw items should not touch anything that may introduce bacteria into your mouth. This includes cutting boards, knifes and countertops; sanitize before re-using.
  • Practice keeping foods properly cooled — Set refrigerator temperature lower than 40 degrees. Put cold items in refrigerator right away after shopping. Refrigerate leftovers within two hours, putting large quantities into smaller, shallow containers to cool more quickly. Use leftovers within seven days. Use foods by expiration date.
  • Cook foods to proper temperatures — This can be checked using a calibrated meat thermometer. Most food packages have the minimum temperature listed on them.

Also note these foods that are not safe for older adults: undercooked meat and fish (sushi), refrigerated smoked seafood, unpasteurized dairy, some fresh soft cheeses, raw/undercooked egg, raw sprouts, deli salads, unpasteurized fruit and vegetable juices.

Wisconsin Dairy Hit With Raw Milk Penalty

The owners of a Pepin County dairy, Roland and Diana Reed of Arkansaw, have agreed to penalties stemming from a foodborne illness outbreak that sickened 32 Durand High School students and coaches in September 2014, said food safety officials today. The Wisconsin Department of Agriculture, Trade and Consumer Protection’s (DATCP) announcement comes after a thorough review of the investigation report written by the Wisconsin Department of Health Services (DHS).

“After reviewing the circumstances described in the final DHS epidemiological and laboratory report, we have determined that the farm violated current statutes and rules by distributing unpasteurized milk in an unauthorized manner, so we are taking appropriate action,” said Dr. Steve Ingham, administrator of the Division of Food Safety for DATCP.

The Reeds have agreed to a DATCP plan that includes suspending the farm’s Grade A permit for 30 days.  If the farm violates the conditions of the agreement within three years, the Grade A permit will be suspended again for 150 days for the current violation and their Grade A permit will be revoked for no less than six months for the additional violation. After revocation, the Reeds must reapply to be considered again for Grade A status.

“Our goal is to prevent a reoccurrence by changing the practices that led to this outbreak,” Ingham says. “We take our responsibility to protect public health seriously and uniformly enforce the law.”

Arizona, Missouri and New Mexico Hardest Hit in Listeria Apple Outbreak

Arizona – 5
California – 3
Colorado – 1
Minnesota – 4
Missouri – 5
Nevada – 1
New Mexico – 6
North Carolina – 1
Texas – 4
Utah – 1
Washington – 1
Wisconsin – 1

The Centers for Disease Control and Prevention (CDC) reports a total of 35 people infected with the outbreak strains of Listeria monocytogenes were reported from 12 states.  Of these, 34 people were hospitalized. Listeriosis contributed to at least three of the seven deaths reported.  Eleven illnesses were pregnancy-related (occurred in a pregnant woman or her newborn infant), with one illness resulting in a fetal loss.  Three invasive illnesses (meningitis) were among otherwise healthy children aged 5–15 years.  Twenty-eight (90%) of the 31 ill people interviewed reported eating commercially produced, prepackaged caramel apples before becoming ill.  The Public Health Agency of Canada (PHAC) identified one case of listeriosis in Canada that is genetically related to the U.S. outbreak.

On January 6, 2015, Bidart Bros. of Bakersfield, California voluntarily recalled Granny Smith and Gala apples because environmental testing revealed contamination with Listeria monocytogenes at the firm’s apple-packing facility.  On January 18, 2015, FDA laboratory analyses using whole genome sequencing (WGS) showed that these Listeria isolates were highly related to the outbreak strains.  Happy Apples, California Snack Foods, and Merb’s Candies each announced a voluntary recall of commercially produced, prepackaged caramel apples.

Marler Clark, The Food Safety Law Firm, is the nation’s leading law firm representing victims of Listeria outbreaks. The Listeria lawyers of Marler Clark have represented thousands of victims of Listeria and other foodborne illness outbreaks and have recovered over $600 million for clients.  Marler Clark is the only law firm in the nation with a practice focused exclusively on foodborne illness litigation.  Our Listeria lawyers have litigated Listeria cases stemming from outbreaks traced to a variety of foods, such as caramel apples, cantaloupe, cheese, celery and milk.

Bidart Listeria Apple Outbreak Over After 37 Sickened

CDC collaborated with public health officials in several states and with the U.S. Food and Drug Administration (FDA) to investigate an outbreak of Listeria monocytogenes infections (listeriosis). Joint investigation efforts indicated that commercially produced, prepackaged caramel apples made from Bidart Bros. apples were the likely source of this outbreak.

Public health investigators used the PulseNet system to identify illnesses that were part of this outbreak. PulseNet is the national subtyping network of public health and food regulatory agency laboratories coordinated by CDC. DNA “fingerprinting” is performed on Listeria bacteria isolated from ill people using techniques called pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS).

The 35 ill people included in this outbreak investigation were reported from 12 states: Arizona (5), California (3), Colorado (1), Minnesota (4), Missouri (5), Nevada (1), New Mexico (6), North Carolina (1), Texas (4), Utah (1), Washington (1), and Wisconsin (3). Illness onset dates ranged from October 17, 2014, to January 6, 2015. Eleven illnesses were associated with a pregnancy (occurred in a pregnant woman or her newborn infant). One fetal loss was reported. Among people whose illnesses were not associated with a pregnancy, ages ranged from 7 to 92 years, with a median age of 62 years, and 33% were female. Three invasive illnesses (meningitis) occurred among otherwise healthy children aged 5–15 years. Thirty-four people were hospitalized, and listeriosis contributed to at least three of the seven deaths reported.

The Public Health Agency of Canada (PHAC) identified two cases of listeriosis in Canada with the same PFGE patterns as those seen in the U.S. outbreak. More detailed testing using WGS showed that the isolate from only one of the two cases was genetically related to the U.S. outbreak. That person reported eating a caramel apple.

On January 6, 2015, Bidart Bros. of Bakersfield, California, voluntarily recalled Granny Smith and Gala apples because environmental testing revealed contamination with Listeria monocytogenes at the firm’s apple-packing facility. The recall included all Granny Smith and Gala apples shipped from its Shafter, California, packing facility in 2014. On January 8, 2015, FDA laboratory analyses using PFGE showed that environmental Listeria isolates from the Bidart Bros. facility were indistinguishable from the outbreak strains. On January 18, 2015, WGS found that these isolates were highly related to the outbreak strains. In addition, WGS showed that Listeria isolates from whole apples produced by Bidart Bros., collected along the distribution chain, also were highly related to the outbreak strains.

Three firms that produce caramel apples issued voluntary recalls after receiving notice from Bidart Bros. that there may be a connection between Bidart Bros. apples and this listeriosis outbreak. On December 24, 2014, Happy Apple Company of Washington, Missouri, voluntarily recalled Happy Apples brand caramel apples with a best use by date between August 25 and November 23, 2014. On December 31, 2014, Happy Apple Company expanded the recall to include Kroger brand caramel apples produced by Happy Apple Company with a best use by date between September 15 and November 18, 2014. On December 27, 2014, California Snack Foods voluntarily recalled Karm’l Dapple brand caramel apples with a best use by date between August 15 and November 28, 2014. On December 29, 2014, Merb’s Candies of St. Louis, Missouri issued a voluntary recall of Merb’s Candies Bionic Apples and Double Dipped Apples that would have been available from September 8 through November 25, 2014.

Marler Clark, The Food Safety Law Firm, is the nation’s leading law firm representing victims of Listeria outbreaks. The Listeria lawyers of Marler Clark have represented thousands of victims of Listeria and other foodborne illness outbreaks and have recovered over $600 million for clients.  Marler Clark is the only law firm in the nation with a practice focused exclusively on foodborne illness litigation.  Our Listeria lawyers have litigated Listeria cases stemming from outbreaks traced to a variety of foods, such as caramel apples, cantaloupe, cheese, celery and milk.

New Jersey School Cafeteria Worker With Hepatitis A

The Passaic New Jersey Superintendent of Schools sent letters to parents and staff members alerting them that a high school employee had been diagnosed with Hepatitis A by their personal doctor.

Anyone who bought food from the Passaic High School teachers cafeteria between Jan. 15th and Jan. 30th was urged to be on the lookout for symptoms.

Symptoms include fatigue, fever and vomiting.

In the letter, superintendent Pablo Munoz said: “The school district immediately notified local health officials about the diagnosis and is currently following every recommendation of these health care professionals. This morning I met with all the school principals, school leaders and staff to discuss this diagnosis of an employee. The school district is sending letters home about the diagnosis of Hepatitis A and providing details about where they can get additional information. While local health officials believe that the chance of students becoming ill is small, we will continue to take every precaution recommended by them.”

Munoz told parents that local and state officials believe the chances of children becoming ill is small, but that they should be aware of several facts:

Hepatitis A is an illness of the liver caused by infection with the Hepatitis A virus.

The virus is shed in the stool of the infected person.

People become infected with Hepatitis A by swallowing the virus. This can occur when an individual eats or drinks food or water contaminated with Hepatitis A virus, or has direct contact with an infected person who has poor personal hygiene.

An individual infected with Hepatitis A, may display a range of symptoms including:

  • Fever
  • Fatigue
  • Poor appetite
  • Vomiting or abdominal discomfort
  • Dark colored urine
  • Clay-colored (pale) stool
  • Yellow discoloration of skin and whites of the eye (a condition known as jaundice)

Young children with Hepatitis A usually do not display symptoms, yet may be a source of infection to close household contacts by sharing food and/or eating or drinking utensils.

No specific medications, including antibiotics, are indicated for the treatment of Hepatitis A. Most individuals fully recover, without treatment, within a few weeks.