The U.S. Centers for Disease Control & Prevention has traced Salmonella Typhimurium infections to exposure in clinical and teaching laboratories, according to an April 28 report. The strain involved in the illnesses is one that is commercially available for use in microbiology labs.
The outbreak identified by CDC involves 73 people from 35 states, with the biggest number (six) from Pennsylvania. Of those 73, 44 had contact with a microbiology laboratory in the week before they became ill. Salmonella causes diarrhea, fever, and abdominal cramps, and usually lasts 4-7 days.
Notably, what happened in the lab didn’t stay in the lab: “several children who live in households with a person who works or studies in a microbiology laboratory have become ill with the outbreak strain,” the CDC report says. In some of those cases, Nature reports, the laboratory worker didn’t get ill–he or she just passed it on to household members. One person died from the outbreak but CDC doesn’t say who it was; 10 others were hospitalized.
The CDC report contains some reminders of good microbiology lab practices. Change “bacteria” to “chemicals” and it’s good advice for chemists, too:
- Be aware that bacteria used in microbiology laboratories can make you or others who live in your household sick, especially young children, even if they have never visited the laboratory. It is possible for bacteria to be brought into the home through contaminated lab coats, pens, notebooks and other items that are used in the microbiology laboratory.
- Persons working with infectious agents, including Salmonella bacteria, must be aware of potential hazards, and must be trained and proficient in biosafety practices and techniques required for handling such agents safely, including:
- Wash hands frequently while working in and immediately after leaving the microbiology laboratory and follow proper hand washing practices. This is especially important to do before preparing food or baby bottles, before eating and before contact with young children.
- Do not bring food, drinks or personal items like car keys, cell phones and mp3 players into the laboratory. These items may become contaminated if you touch them while working or if you place them on work surfaces.
- Do not bring pens, notebooks, and other items used inside of the microbiology laboratory into your home.
- Wear a lab coat or other protective uniform over personal clothing when working in a microbiology laboratory; leave it in the laboratory when you are finished. Remove protective clothing before leaving for non-laboratory areas (e.g., cafeteria, library, or administrative offices). Dispose of protective clothing appropriately or deposit it for laundering by the institution. Take it out of the laboratory only to clean it.
- If you work with Salmonella bacteria in a microbiology laboratory, watch for symptoms of Salmonella infection, such as diarrhea, fever and abdominal cramps. Call your health care provider if you or a family member has any of these symptoms.