The multi-year Salmonella Typhimurium outbreak linked to pet african dwarf frogs may have finally come to an end. The CDC reports that 224 people were sickened from 2009-2011 with the same strain of Salmonella typimurium, with 65% of those people reporting contact with frogs in the week before illness (mostly in the home). Unfortunately, as one might expect, most of the case-patients in the outbreak were kids, and at least 37 people had to be hospitalized.
The median age of patients in this outbreak was 5 years (range: <1–67 years), and 70% (156 of 223) were aged <10 years. Approximately 52% (111 of 215) were female. No deaths have been reported, but 30% (37 of 123) of patients were hospitalized. Sixty-five percent (56 of 86) of patients interviewed reported contact with frogs in the week before illness; 82% (45 of 55) reported that this contact took place in the home. Of those who could recall the type of frog, 85% (29 of 34) identified ADFs. Median time from acquiring a frog to illness onset was 15 days (range: 7–240 days).
Samples collected during 2009–2011 from aquariums housing ADFs in six homes of patients yielded the S. Typhimurium outbreak strain. Traceback investigations conducted during 2009–2011 from 21 patient homes and two ADF distributors identified a breeder in California as the common source of ADFs. This breeder sells ADFs to distributors, not directly to pet stores or to the public. Environmental samples collected at the breeding facility in January 2010, April 2010, and March 2011 yielded the outbreak strain. Based on these epidemiologic, traceback, and laboratory findings, the breeder voluntarily suspended distribution of ADFs on April 19, 2011. Public health officials are working with the breeder to implement control measures.
The most effective control measure for this breeder would be to pick another profession. Any outbreak of the same strain of Salmonella Typhimurium that lasts 2 years suggests that there probably wasn’t any effort to control the contamination in the breeder’s “flock,” or stock, at all . . . a la Wright County Egg outbreak, where we saw a half-billion egg recall due largely to the unchecked spread of Salmonella in the breeding and egg-laying environment.
Who is this breeder, and what is his culpability in this outbreak? Depends on what he knew, when he knew it, and what he did in response.