Despite flood of news stories, experts warn against unneeded tetanus shots after Harvey

For health care reporters covering Hurricane Harvey, there is no shortage of issues to address, whether it’s the health hazards of polluted flood waters, unexpected insect threats (fire ant rafts, anyone?) or the long-term risks of mold growth.

But there is one fear that sometimes circulates in news stories after floods that should be shelved, according to a story from STAT.

In a word, tetanus. Unlike what many of us may think, floods do not lead to increases in tetanus infections, STAT reports, and calls to get vaccinated may cause more harm than good.

Yet this “old wives’ tale” persists. The Hill reported that Texas representative Pete Sessions warned residents via Twitter to get tetanus shots after wading through dirty water, for example. NPR’s headline urged residents to “Stay Safe And Get A Tetanus Shot.,” citing recommendations from Texas public health officials. Meanwhile, the Washington Post said “Health officials are urging people to get tetanus booster shots to protect themselves against the disease.” Quartz reported that “officials are worried about the spread of tetanus.” [Editor’s note: NPR’s headline has been updated to the more appropriate: “Stay Out Of Flood Water, Texas Health Officials Urge.”]

STAT suggests otherwise, citing the CDC’s worker safety page:

The Centers for Disease Control and Prevention does not recommend tetanus shots for people who have been in floodwaters. “Exposure to flood waters does not increase the risk of tetanus, and tetanus immunization campaigns are not needed,” the CDC website states.

The NPR story, to its credit, does not claim that tetanus risk is high. And yet, the headline–urging tetanus shots–prioritizes an extremely low health risk. The headline writer may have focused on this section near the top of the article:

The state has already begun filling requests for tetanus vaccinations and is sending supplies of the vaccine to the affected areas. The Centers for Disease Control and Prevention recommends adults get a tetanus booster every 10 years; the bacteria can enter the body through breaks in the skin and can cause serious illness. 

Technically, that’s true. Tetanus spores are found in soil and can enter people’s bodies through wounds. And yet, on average only 30 cases of tetanus occur in the U.S. each year.

“If you’re just in the water, no matter how dirty it is, there’s no risk,” says Dr. Dan Mayer, a HealthNewsReview.org contributor and Professor Emeritus of Emergency Medicine at the Albany Medical College. “You don’t get tetanus from just contact, there has to be an open wound.”

Even with a wound, the risk is very small. “The interesting thing is when you look back on past data,” Mayer says, “Is there an increase in tetanus after a flood? No.”

Public health experts, including those at the University of Minnesota Center for Infectious Disease and Research Policy, say it’s a good idea for everyone to be up to date on their tetanus boosters, regardless of whether they’ve been in a flood. And anyone who suffers a wound in a flood area should take the situation seriously — including getting a shot if they are unsure of their tetanus status.

But that’s quite a different message than recommending tetanus shots for everyone in a flood zone.

Tetanus is a serious and sometimes fatal illness. No doubt about it — it’s scary.

So what’s the harm in calling for immunizations against tetanus after a flood?

When fear takes over about a deadly disease, resources can get diverted from more pressing and widespread health concerns.

It’s happened before, STAT reports:

Dr. Kathleen Schrank, a professor of emergency medicine at the University of Miami, said … that after Hurricane Andrew, which walloped Miami 25 years ago — the anniversary was last Thursday — the demand for tetanus shots swamped the health care system.

“People think of it themselves and suddenly get very panicked about it,” she said. “So they go seek care for it and that overwhelms the local clinic or urgent care centers or health departments at a time when they need to be focused on much more likely threats.”

Based on NPR’s reporting, it sounds like this exact scenario may be unfolding in Texas right now. It’s up to journalists to help counter misinformation from well-intended politicians, public health officials and others.