Hurricane Ida has pummeled Louisiana's parishes, strapping hospital and health resources as thousands remain without power.
Experts worry Ida's impact will worsen COVID-19 spread in the state's low-lying parishes, where vaccination rates are low - in some only about a third of the population - and cases have surged to all-time highs.
Crowded shelters, delayed treatments and inundated hospitals and intensive care units are a recipe that put under-vaccinated communities at dire risk for more infections, experts said. Forty-one percent of Louisiana's population has been vaccinated, according to the Centers for Disease Control and Prevention. The unvaccinated account for the majority of deaths and hospitalizations.
"This is a pandemic tinderbox," said pediatrician Irwin Redlener, founding director of Columbia University's National Center for Disaster Preparedness.
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Redlener, who started medical relief and public health programs in Gulf Coast states after Hurricane Katrina 16 years ago, said that although evacuation and shelters are necessary, they can help the virus spread because social distancing is difficult. Emergency shelters could become "superspreader" environments, he said.
"We end up with an untenable situation," he said. "It's a very bad combination of circumstances. It's not at all unreasonable to expect a serious exacerbation of COVID-19 in those communities."
Louisiana reported almost 30,000 new cases in the week ending Sunday and more than 400 deaths, a USA TODAY analysis of Johns Hopkins University data shows. About two weeks ago, the state peaked at more than 40,000 cases reported in one week.
Case counts are roughly 15 times as high as they were about two months ago. Deaths are 19 times as high as they were in early July.
In Lafourche Parish, where Ida made landfall, 37% of residents are fully vaccinated, according to the state. The week ending Sunday, the parish recorded more than 800 new COVID-19 cases. Its rate is about 8.45 times the level the CDC considers to be a high level of transmission. The previous week, the parish topped more than 1,400 new cases, setting a record.
People coping with a weather emergency in crowded shelters or other evacuation sites may forget to mask and social distance, said David Abramson, a clinical associate professor at New York University's School of Global Public Health. Abramson launched programs to study long-term child and family health effects after Superstorm Sandy and Hurricane Katrina.
"The biggest concern I have, especially among a largely unvaccinated population, is right now people are going to be focused on what they need to do most immediately," Abramson said. "That question of being in close contact will be almost unavoidable while people are scrambling to attend to all the daily needs that they have."
Community-level resources, such as pharmacy and dialysis centers and other treatment locations, will be affected, delaying treatment for people vulnerable to the virus.
"You've got a susceptible population, and they are unlikely to be able to attend to those kinds of things that will be able to protect them," he said.
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Rachael Piltch-Loeb, a fellow at Emergency Preparedness Research Evaluation and Practice Program at the Harvard T.H. Chan School of Public Health, called the situation a "set of cascading consequences."
"There's probably a limited capacity to treat COVID-19 patients who get severely ill when the health care system is overwhelmed," she said. In addition to the immediate threat to human life and safety because of the storm is a safety net "incredibly tapped (of) resources."
Amesh Adalja, a physician and senior scholar at Johns Hopkins University's Center for Health Security, said the hurricane's aftermath and the pandemic's spread make for a "daunting" dual challenge.
"I see the hurricane synergizing with the problem that's already going on in Louisiana with regards to COVID," he said. "We know from the past with hurricanes like Hurricane Katrina, Superstorm Sandy, that hurricanes can have a disproportionate impact on the health care infrastructure."
Hospitals, which were already at capacity, will have to move into emergency operations during weather emergencies, taxing clinicians and the system further and limiting treatment efficiency.
Combined with the low vaccination rates, the hurricane created a "threat that's going to raise the stakes even higher and just make it even more challenging to operate a hospital," he said.
As of Sunday, there were more than 2,400 COVID-19 patients hospitalized in Louisiana, Gov. John Bel Edwards told The Associated Press. Some hospitals evacuated a small number of patients while others plan to evacuate "once it is safe to do so," according to state health department spokesperson Alyson Neel.
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Evacuations, especially of residents with confirmed COVID-19, are another opportunity for virus transmission, said Arnold Monto, a professor of epidemiology at the University of Michigan School for Public Health.
"The hospitalized who have been evacuated are a problem because they are infected, and once you start moving people around, you can't ensure all the precautions you might have if you were in a room with negative pressure and things like that," he said.
COVID-19 spread could occur among residents unknowingly infected and evacuated to areas with low vaccination rates before the storm made landfall in southern Louisiana Sunday.
"Unfortunately, most of the worst effects of the storm are going to be in the least vaccinated parts of the country, and that may make the impact more severe because people who will be in potential contact to other cases are not vaccinated themselves," Monto said.
Contributing: Adrianna Rodriguez and Mike Stucka
Reach Nada Hassanein at email@example.com or on Twitter @nhassanein_.
This article originally appeared on USA TODAY: Hurricane Ida: Experts worry Louisiana's COVID outbreak will get worse