Notes from the Field: Salmonella from Microbiology lab
We have a two-fer in this week’s CDC Morbidity and Mortality Weekly Report; several “Notes from the Field,” and an outbreak of Salmonella. Imagine my surprise to see that the Salmonella outbreak was from a college microbiology laboratory. Actually, I wasn’t surprised at all, and BIO230 students will recall that I warned of these dangers in our very first class meeting this semester. The CDC reports that a case of salmonellosis was verified by the Maine Center for Disease Control in May 2013, and a second case was additionally reported shortly thereafter. Both patients complained of diarrhea, fever, and nausea, after attending Microbiology lab at a local community college. Molecular characterization of the patient isolates were identical, and further matched the isolate used in the class laboratory exercises.
Members of the Maine state testing laboratory visited the community college lab, and interviewed faculty and students to determine what infection control practices were in place. Survey results indicated that erratic personal protection methods were in place, including inconsistent and improper use of gloves, as well as inconsistent hand washing. Examination of control practices in the laboratory were unable to pinpoint the source of the infection, which may have resulted from direct handling of Salmonella cultures, a spill, or lab equipment that may have become contaminated. Recommendations from review of policies were much in line with the recommendations from the prior Salmonella outbreak. First, personal protective equipment including gloves, proper clothing, lab coats, and safety goggles should be used under all conditions where infection risk exists. Second, lab coats must remain in the laboratory, and can only leave the laboratory after being autoclaved. Third, all personal items such as cell phones must remain outside of the laboratory. Infectious agents may remain viable for extended periods of time, and are easily removed from the controlled laboratory setting on these items. Forth, hand hygiene remains one of the most effective methods for controlling infection in and out of the lab. Adherence to these rules of Microbiology Club will ensure that we have happy students, and happy instructors!