Hidden Hazards after the Hurricane

Death, dismemberment, damage, disruption and distress. These are dangers people face during and immediately after storms like Harvey and Irma. But what about the hidden hazards of hurricanes? Experts from the University of Washington School of Public Health weigh in.


Scott Meschke

Diarrheal diseases

Floodwater and ground water may become contaminated with wastewater and sewage, carrying a whole suite of pathogens, including all the basic diarrheal pathogens. Diarrheal incidence has occurred at some level in all the flooding events I can think of, says Scott Meschke, an associate professor of environmental and occupational health sciences. This isn’t usually a serious concern in the U.S., due in part to quality surveillance methods, but it was an issue after Hurricane Katrina.

Hygiene-related diseases

Every surface and object that has come in contact with floodwater runs a fairly significant risk of being contaminated. This includes household items, kids’ toys, countertops, floors, etc. These items need to be cleaned and disinfected, Meschke warns, and perishables, such as food, should be thrown away.

Chemical exposure

There is potential for acute exposure to toxins in floodwater from big spills or the leaking of chemical contaminants. Chemical exposures have real, long-term concerns for the environment as well.

Animal agriculture issues


Peter Rabinowitz

If animal agriculture facilities and farms are flooded, they not only pose a risk to the animals, but also to the environment, according to Peter Rabinowitz, associate professor of environmental and occupational health sciences and of global health.

If contents of manure lagoons and storage enter water bodies, it could be a source of contamination. This was a problem in Eastern Washington earlier this year with much less flooding, notes Rabinowitz, who heads the Center for One Health Research. Animal carcasses can also contaminate floodwaters.

Contaminated drinking water

After a flood, drinking water could be compromised. Water pipes will need to be flushed, but even that may not get rid of everything, Meschke notes. For example, a bug called Naegleria fowleri is capable of colonizing drinking water systems and it is somewhat resistant to chlorine. The relatively rare, warm water amoeba can cause amebic encephalitis, which has a 95 to 98 percent fatality rate.

Mold growth

Mold growth is a critical concern during the recovery and remediation process, and one that people will be dealing with for months, if not longer, Meschke says. The warm and wet climate in the south create the perfect conditions for mold to thrive. Major health concerns involving mold include skin irritation or damage to the respiratory tract.

Mosquito-borne diseases


Cory Morin

Extreme precipitation from tropical storms and hurricanes often washes out mosquito habitats resulting in an initial drop in the population. However, the population often rises in the following weeks due to the increased habitat created from standing water, says Cory Morin, a research scientist from the Department of Global Health. It is important to note that this only applies to the mosquito population. The pathogen still needs to either exist or be introduced into the area for there to be risk of disease.

Southern Texas and Florida are the only areas in the U.S. to have reported locally acquired dengue, Zika or chikungunya virus, so they are probably at highest risk of transmission, according to Morin. The warm, humid environment combined with the frequency of travelers coming from endemic countries may explain the increased risk in these areas, he notes.

Big picture: Preparedness and resilience

As Hurricanes Harvey and Irma battered the Caribbean and southern U.S., wildfires raged across California, Montana, Oregon and Washington state. What’s more, a deadly magnitude-8.2 earthquake struck Mexico and the worst flooding in decades inundated South Asia.


Nicole Errett

“We’ve seen time and time again that stronger, healthier and more interconnected communities do better following disaster,” says Nicole Errett, a lecturer in environmental and occupational health sciences and expert on emergency preparedness.

Disasters can exacerbate stress, especially for vulnerable populations, by disrupting essential services, interrupting resource channels and limiting access to healthcare. Moreover, low-income and traditionally underserved populations often live in disaster prone regions and are hit the hardest.

“Fortifying community assets and decreasing vulnerabilities can help build healthier, wealthier and more equitable communities, and facilitate their ability to bounce back from a major disaster,” Errett says. “Good public health leads to enhanced community resilience.”

The School of Public Health is committed to creating sustainable communities in Washington and beyond. As part of that vision, SPH works with state, local and tribal partners to enhance emergency preparedness and response systems. For example, the Northwest Center for Public Health Practice, which often hosts emergency preparedness trainings, developed an online portal with more than 400 preparedness and response resources. The center also worked with health departments to evaluate the implementation of innovative communications tools, such as text messaging, during emergencies.


Jeremy Hess

Strengthening resilience to climate change is a focus of the School’s Center for Health and the Global Environment, or CHanGE, a partnership with UW Medicine to develop knowledge, capacity and tools to manage risks to human health caused by global environmental change.

“We have a lot of expertise and a lot of resilience, and that’s important to emphasize,” says CHanGE member Jeremy Hess, associate professor of environmental and occupational health sciences and of global health. “It’s also important to recognize that these hazards are becoming unprecedented. We need to recognize that what’s going to be needed to preserve, protect and recover may be different from what had been required before.”