Salmonella outbreaks linked to hospitals; doctors warned

Public health officials are calling on physicians to consider the possibility of Salmonella when faced with a patient who has diarrhea and may have had recent contact with the medical system -- either as a patient, hospital visitor or health care worker, particularly in New Hampshire and elsewhere in the Northeast.

"Think about Salmonella, and test the patient," said Jose Montero, MD, state epidemiologist and chief of communicable disease control with the New Hampshire Dept. of Health and Human Services.

This advice is being given because public health officials from the Centers for Disease Control and Prevention and in New Hampshire are in the process of tracking a multistate outbreak of Salmonella oranienburg. The initial cases were detected in that Northeast state, and, at press time, officials had found 34 people throughout the region who all had contact with health care facilities and became ill. Those investigating the outbreak say it could be a national problem related to food consumed at these facilities and have initiated a case-control study to determine the cause.

"We have found eight states with cases that match this pattern, but it may grow," said Elizabeth Daly, MPH, a foodborne disease epidemiologist with the New Hampshire DHHS who is leading the investigation. "We're trying to find something that's common to all of them."

Although the source of this outbreak was unknown at press time, many experts suspect -- because it is geographically widespread -- that it may not be the result of hygiene problems at these institutions. Instead, since so many hospitals have been impacted by the same organism, it is almost certain that the contamination occurred somewhere else and then was delivered to the facilities.

But whatever the source, this incident does have many infectious disease experts worried, particularly because the pathogen puts hospital patients who are already sick at even greater risk.

"It's so rare to find Salmonella in the hospital. And, when outbreaks do occur, they're devastating," said Thomas Fekete, MD, professor of medicine and chief of infectious diseases at Temple University School of Medicine in Philadelphia.

According to CDC data, the various types of Salmonella infect millions and kill more than 500 annually. Those who are very young, very old or otherwise frail are considered most likely to die or develop severe disease.

Antibiotic discussion

Experts also say this incident should add to the discussion of the importance of the judicious use of antibiotics and the debate regarding acid suppression in hospital settings.

Antibiotic use long has been linked to the development of resistant organisms, but it can also change the normal gut flora that can provide some protection against various foodborne pathogens. More recently, proton pump inhibitors and H2 blockers in this environment have been linked to a higher risk of Clostridium difficile. Some wonder whether such practices are factors in these Salmonella cases.

"Patients might be more susceptible because their protective mechanisms, such as acid in the stomach, may be suppressed," said Donald J. Kennedy, MD, professor of internal medicine and infectious diseases at Saint Louis University.

Those who work with infectious disease also say this incident further sends home the message that Salmonella is an important pathogen that demands as much respect, if not more, than infectious agents that make headlines.

"We ought to be worried about [Salmonella], not mad cow disease or bird flu," said Marc Siegel, MD, associate professor of medicine at New York University School of Medicine and the author of False Alarm: The Truth About the Epidemic of Fear.

Suspected cases should be reported via e-mail to David Blossom in the CDC's Division of Healthcare Quality Promotion ([email protected]" target="_blank">link).