Answer to a Recent Question about Bacterial Contamination from Sewage Exposure in New Orleans, Post-Katrina
By John G. Bartlett, M.D. and Luciana Borio, M.D., September 12, 2005
Last week, one of our subscribers wrote asking for advice about prophylaxis for bacterial contamination for those exposed to sewage while working in New Orleans following Hurricane Katrina:
Question: I just got back from a week in New Orleans in the areas that were flooded but could be walked in. I observed the daily gross contamination of law enforcement officers and other responders by what appeared to be sewage, including human waste. Due to the circumstances, the usual infection control measures such as hand washing were totally absent. There is a debate about antibiotic prophylaxis for bacterial pathogens from human waste for responders. I can tell you that I and every physician I met were taking ciprofloxacin for prophylaxis. Many of the responders and police I worked with had fecally contaminated sludge and water on their hands, feet, and clothes almost all the time they were working. Relief workers were able to shower after their shifts, but while working they were not able to wash their hands, and they didn’t have gloves. I also treated responders who had fallen off their boats and actually drank this water. The guidelines I’ve seen simply recommend hand washing. Can you please advise about prophylaxis for bacterial contamination as I’ve described above?
Answer: There are no clear guidelines for the prevention of bacterial contamination for those exposed to sewage. The problem of fecal contamination of water in New Orleans and other similarly affected areas seems analogous to problems encountered with travel to developing countries where food and water contaminated with fecal matter are the main sources of infection with enteric pathogens. The majority of cases of acute traveler’s diarrhea are due to enterotoxigenic E. coli, enteroaggregative E..coli, shigella, salmonella, or campylobacter. There are many idiosyncrasies that are specific to the geographic area in New Orleans, but the experience and recommendations are generalizable, as follows:
Antimicrobial prophylaxis is not routinely indicated for healthy individuals because there is the potential for adverse effects, particularly if taken for an extended period of time, and treatment with antibiotics for established diarrhea is very effective.
For moderate diarrhea, defined as <3 loose stools every 24 hours, with no fever, loperamide may be used, as follows: 4 mg x 1, followed by 2 mg after each loose stool, up to 16 mg a day. Loperamide is contraindicated in the presence of fever or blood in stool.
For severe diarrhea, defined as >3 stools every 24 hours, or diarrhea with fever or bloody stools, initiation of antimicrobial therapy is warranted. Recommended regimens include: Ciprofloxacin 500 mg bid x 3 days; Levofloxacin 500 mg qd x 3 days; Azithromycin 1 gm x 1 dose or 500 mg qd x 3 days. Azithromycin is the preferred drug to be used in pregnancy.
The CDC does not recommend Hepatitis A vaccination for volunteers because the vaccine requires 2 doses, protection is not immediate, and the risk is considered very small—it has been more than 15 years since a waterborne hepatitis A outbreak occurred in the U.S. However, the Louisiana Department of Health and Hospitals has ordered hepatitis A vaccine for emergency responders. Volunteers should be up-to-date on tetanus, diphtheria and hepatitis B vaccines.
New: Guidelines for Managing Disaster Survivors with HIV/AIDS: The American Academy of HIV Medicine (AAHIVM) and the HIV Medicine Association (HIVMA) developed succinct and clear guidelines for the management of disaster survivors with HIV/AIDS. The guidelines were prepared to provide guidance to clinicians who are not HIV specialists. In addition, non-HIV specialists are encouraged to call the NIH Medical Consultation Services at 1-866-887-2842 or the National HIV/AIDS Clinical Consultation Center at 1-800-933-3413 to consult with HIV experts regarding the management of disaster survivors with HIV/AIDS.