The DuPage County Health Department now counts 125 confirmed victims of the shigella outbreak linked to a Subway restaurant in Lombard, Illinois, according to department spokesperson Dave Hass.  The restaurant voluntarily closed on March 4, and has remained shuttered ever since.  Meanwhile, multiple lawsuits have been filed against the restaurant, including Ron and Sarah Bowers v. Neel Subway, Inc., Barbara Romero v. Neel Subway, Inc., and Michael Carpino v. Neel Subway, Inc.

Thirteen of the 125 confirmed outbreak cases required hospitalization as a result of their illnesses, but that is only half, and maybe less, of the story.  There are many, many more victims of this outbreak who are not included in the number 125 announced by DuPage County.  These other victims are not included because, for any of a whole host of reasons, they did not have a stool sample that tested positive for the outbreak strain of Shigella.  Nonetheless, and from personal experience after having talked to, now, close to 100 victims of this outbreak, there are many more than 13 who have required hospitalization after suffering particularly severe illnesses.

And we still have not sufficiently plumbed the depths of this large outbreak, because it is probable that a certain percentage of outbreak victims will go on to have chronic health problems as a result of their infections.  Two of the most common "chronic health problems" that can follow  foodpoisoning illnesses are post-infectious irritable bowel syndrome (IBS) and reactive arthritis (also sometimes called Reiter’s syndrome). 

Post-infectious IBS

A recently-published study surveyed the extant scientific literature and noted that post-infectious irritable bowel syndrome (PI-IBS) is a common clinical phenomenon first-described over five decades ago. The Walkerton Health Study further notes that:

Between 5% and 30% of patients who suffer an acute episode of infectious gastroenteritis develop chronic gastrointestinal symptoms despite clearance of the inciting pathogens.

In terms of its own data, the “study confirm[ed] a strong and significant relationship between acute enteric infection and subsequent IBS symptoms.” The WHS also identified risk-factors for subsequent IBS, including: younger age; female sex; and four features of the acute enteric illness—diarrhea for > 7days, presence of blood in stools, abdominal cramps, and weight loss of at least ten pounds.

Irritable bowel syndrome (IBS) is a chronic disorder characterized by alternating bouts of constipation and diarrhea, both of which are generally accompanied by abdominal cramping and pain. In one recent study, over one-third of IBS sufferers had had IBS for more than ten years, with their symptoms remaining fairly constant over time. IBS sufferers typically experienced symptoms for an average of 8.1 days per month.

As would be expected from a chronic disorder with symptoms of such persistence, IBS sufferers required more time off work, spent more days in bed, and more often cut down on usual activities, when compared with non-IBS sufferers. And even when able to work, a significant majority (67%), felt less productive at work because of their symptoms. IBS symptoms also have a significantly deleterious impact on social well-being and daily social activities, such as undertaking a long drive, going to a restaurant, or taking a vacation. Finally, although a patient’s psychological state may influence the way in which he or she copes with illness and responds to treatment, there is no evidence that supports the theory that psychological disturbances in fact cause IBS or its symptoms.

Reactive arthritis

The term reactive arthritis refers to an inflammation of one or more joints, following an infection localized at another site distant from the affected joints. The predominant site of the infection is the gastrointestinal tract. Several bacteria, including Salmonella, induce septic arthritis. The resulting joint pain and inflammation can resolve completely over time or permanent joint damage can occur.

The reactive arthritis associated with Reiter’s may develop after a person eats food that has been tainted with bacteria. In a small number of persons, the joint inflammation is accompanied by conjunctivitis (inflammation of the eyes), and uveitis (painful urination). This triad of symptoms is called Reiter’s Syndrome. Reiter’s syndrome, a form of reactive arthritis, is an uncommon but debilitating syndrome caused by gastrointestinal or genitourinary infections. The most common gastrointestinal bacteria involved are Salmonella, Campylobacter, Yersinia, and Shigella. Reiter’s syndrome is characterized by a triad of arthritis, conjunctivitis, and urethritis, although not all three symptoms occur in all affected individuals.

Although the initial infection may not be recognized, reactive arthritis can still occur. Reactive arthritis typically involves inflammation of one joint (monoarthritis) or four or fewer joints (oligoarthritis), preferentially affecting those of the lower extremities; the pattern of joint involvement is usually asymmetric. Inflammation is common at enthuses—i.e., the places where ligaments and tendons attach to bone, especially the knee and the ankle.