The immediate impact of recent hurricanes Harvey, Irma and Maria was ferocious and impossible to miss, from the loss of life to untold amounts of property damage.

But as the winds died down and the rains ceased, and people begin to put their lives back together, history and research shows that for many, a quieter crisis ensues — a storm rages within.

Comprehensive reviews of the mental health effects of natural and human-made disasters have found “that, for hurricanes, up to half of those who survive being directly in the storm’s path risk developing post-traumatic stress disorder,” notes a perspective piece published in the Journal of the American Medical Association in September, and “10 percent of those who live in the vicinity of the storm may also develop PTSD.”

Hurricanes can raise anxiety levels and have a significant effect on mood. “[Rates of] depression and a range of other mental illnesses are increased after these events, including use of substances like alcohol and other drugs,” says Dr. Sandro Galea, dean of the School of Public Health at Boston University, and a co-author of the JAMA perspective piece, who has extensively studied the mental health consequences of disasters. “This is well documented, and we know that it affects most people who are most directly affected by these events — meaning those who are injured, or those who lost property or loved ones. It also — at a lower prevalence — affects those who are in the area around the event.”

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The psychological impact a catastrophic storm has depends, in large part, on the stressors it precipitates. These can range from the frightful experience of riding out a hurricane and experiencing the storm’s fury firsthand; to grieving the loss of a friend or family member who died in the storm; to not having access in the immediate aftermath to basic necessities, like food, clean drinking water or medication. Some also struggle with financial strain and logistical issues associated with extensive property damage.

Some hurricane survivors, like those in Puerto Rico — which faces an ongoing humanitarian crisis in the aftermath of the devastation caused by Hurricane Maria — face a deluge of stressors that won’t relent. If you’re exposed directly to the hazards — like residents in Puerto Rico who experienced wind and rain and mudslides — and you can’t escape, that can be pretty traumatizing, says James Shultz, director of the Center for Disaster and Extreme Event Preparedness at the University of Miami Miller School of Medicine, who co-authored the JAMA piece with Galea. “Then what is happening is afterwards the psychological impact doesn’t cease; in fact, it continues or in some cases worsens, because in the aftermath you deal with the losses and the life changes,” he says.

Studies show that individual factors, like a past history of mental illness, can make it more likely a person will also face psychological issues after a natural disaster. Being low-income, having limited means or access to transportation that makes it more difficult to evacuate (if that’s even an option) or repair damaged property, can also increase the disaster-related stressors a person faces. But the mental havoc a hurricane can wreak isn’t limited by demographics, though each storm rains down unique hazards.

With Harvey, it was the rain — as the wind speeds declined — that proved most devastating. Over the period of five days, Harvey dumped more than 33 trillion gallons of rain on Texas and Louisiana, setting a continental U.S. record for rainfall at nearly 52 inches. Shultz, who evacuated when Irma bore down on Florida, noted people in Houston didn’t have the same opportunity to get out well in advance of the fast developing storm and were exposed to rainfall and floods.

Commonly, it’s the hurricane force winds that are the most significant concern, though flooding can be a significant strain on mental health — putting people in immediate harm’s way, leaving some stranded and wreaking havoc on housing, as happened with Hurricane Katrina in New Orleans in 2005.

“What we saw was an elevation in depression, anxiety, and we also saw symptoms of post-traumatic stress in a large number of the survivors,” says Jean Rhodes, a professor of psychology at the University of Massachusetts Boston, who led research evaluating the effects of Katrina on the mental and physical health of low-income, predominantly African-American, single mothers who lived through it. (The participants had been enrolled in previous unrelated research she’d been doing before the hurricane, serendipitously providing baseline information on their mental health that was used for comparison purposes.)

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The humanitarian issues in Puerto Rico following Hurricane Maria are “much more reminiscent of Katrina than the more kind of integrated response that we saw in Houston and Florida. It’s a little bit more chaotic,” she points out. “If you remember the scenes of desperation on rooftops, and the problems that occurred at the [New Orleans] Convention Center in the aftermath, those are the kinds of things that were very, very troubling.”

Experts say rebuilding in brick-and-mortar type ways is psychologically beneficial, too — and that any governmental and societal response that helps people in Puerto Rico, Houston and elsewhere get back on their feet is likely to reduce the mental health burden for survivors. “Research has shown that replenishing social and economic resources that will restore living conditions for those affected by the hurricane will do as much, if not more, for the protection of health and the promotion of resilience than do short-term, individualized medical or psychological interventions,” Shultz and Galea write in JAMA.

However, experts emphasize that people who feel they may be suffering from mental health issues, like PTSD, should seek professional help. Be alert to warning signs and risk factors for emotional distress that may be the result of a disaster, from eating too much or too little to trouble sleeping or having unexplained stomachaches or headaches, says Capt. Maryann Robinson, chief of the Emergency Mental Health & Traumatic Stress Services Branch at the Substance Abuse and Mental Health Services Administration. SAMHSA’s Disaster Distress Helpline provides 24/7 crises counseling and support to people experiencing emotional distress related to disasters.

Resist the urge to go it alone or isolate, too, and pay attention to other possible signs or symptoms, such as if you’re constantly on edge, hypervigilant or suffer from intrusive thoughts, which can occur with PTSD. Irrespective of whether a person has a mental health concern, survivors are advised to reach out to family, friends and others for support in dealing with the aftermath of a catastrophic storm — both logistically and emotionally.

Studies on the mental health impact of disasters illuminate both lingering storm clouds and a potential silver lining for hurricane survivors. Psychological effects can be lasting, but people usually begin to show improvements once they’re safe and able to start putting their lives back together; and research shows people tend to be resilient in the aftermath of the storm.

Rhodes found many Katrina survivors also exhibited what’s referred to as post-traumatic growth. “The women in our sample weren’t just trying to put their life back together exactly as it was, but they were realigning their priorities, and beginning to value things in new ways — value life, value relationships, begin to kind of reframe the rest of their life,” Rhodes says. “So it was a turning point for many women in our study. That’s not to say it didn’t come with a tremendous amount of stress. In fact, the stress itself was an engine of that growth.”

[See: Am I Just Sad — or Actually Depressed?]

To begin that renewal process, though, typically requires turning the page — no longer being in the midst of the crisis, where many today, like residents of Puerto Rico, still find themselves. “One of the things we know from the research is that you need kind of a safe distance to begin to heal,” Rhodes says. “If you’re continuing to suffer the consequences every day of the disaster in new ways, it’s harder to begin the healing process.”

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The Road Map for Mental Wellness After a Hurricane originally appeared on usnews.com