Malaria Reemerges in the US for the First Time in 20 Years

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Malaria, an infectious disease once a leading cause of death in the United States, was eradicated in the 1950s. However, a recent health warning issued by the U.S. Centers for Disease Control and Prevention (CDC) has raised concerns about a potential resurgence of this deadly mosquito-borne disease.

So far, five cases of malaria infection that occurred on U.S. soil have been identified—four in Florida and one in Texas, Reuters reported. This is the first local spread of the disease in 20 years.

The first case in Florida was diagnosed on May 26 in Sarasota County, while Texas officials announced on June 23 that a state resident who worked outdoors in Cameron County had been infected.

Florida officials determined that the cause of malaria in these cases was the Plasmodium vivax species, and all four patients received treatment and successfully recovered.

Texas officials are investigating whether there have been any additional infections in the state, noting that the most recent locally acquired case in Texas was in 1994.

The CDC’s health warning indicates a growing risk for the U.S. population, Dr. Eric Cioè-Peña, emergency medicine physician at Staten Island University Hospital and vice president of Global Health, told The Epoch Times.

“Malaria is a serious disease that can be fatal, and its presence within the U.S. is a cause for concern,” he said.

What Is Causing the Comeback?

Dr. Cioè-Peña noted that the emergence of new malaria cases in the United States could be attributed to various factors.

“One possibility is the importation of the disease by travelers returning from regions where malaria is prevalent,” he said.

A 2013 study found evidence suggesting that malaria is no longer restricted to forested regions and is influenced mainly by population movements, particularly those moving to agricultural regions, as stagnant waters in such areas provide suitable breeding sites for mosquitoes.

The United States is currently experiencing an illegal immigration crisis, with an “unprecedented” number of people crossing the southwest border illegally, according to Customs and Border Protection (CBP).

“Nationwide, CBP’s apprehensions for [fiscal year] 2019 totaled 1,148,000, more than 970,000 along the Southwest border alone,” CBP Acting Commissioner Mark Morgan said in a statement. “This is a staggering 88 percent higher than the fiscal year 2018. These are numbers that no immigration system in the world can handle, not even this country.”

This influx of illegal immigrants is likely a significant factor contributing to the reemergence of diseases previously thought to be virtually eliminated in the country.

An article in the Journal of Travel Medicine highlighted that migrants are “disproportionately affected by preventable travel-related diseases, including malaria, typhoid, and hepatitis.” This is attributed to their “poor uptake of pre-travel prophylaxis and vaccination measures.”

Dr. Cioè-Peña also claimed that global warming had triggered the expansion of mosquito habitats, likely contributing to the problem.

He also expressed concern about lapses in mosquito control measures, warning that they could potentially lead to a resurgence of the disease.

Could Malaria Become Endemic in the US?

In 1999, the first case of West Nile virus, another mosquito-borne illness, was identified in New York, and it rapidly spread to become an endemic disease across the United States.

Within three years, the virus expanded from a six-county area surrounding metropolitan New York to the West Coast. It established itself in 44 states, the District of Columbia, and five Canadian provinces.

“While it’s possible for malaria to become endemic again, it’s too early to make definitive predictions,” Dr. Cioè-Peña said, noting that several factors will influence the outcome, such as the effectiveness of public health responses, climate conditions, and human behaviors. “Nevertheless, the situation serves as a reminder of the need for continuous vigilance against infectious diseases, even those considered eradicated, and for ongoing investments in public health infrastructure.”

Symptoms, Treatment, and Vaccination

The CDC warns about malaria’s seriousness and potential fatality. The disease is caused by parasites commonly transmitted through a specific type of mosquito. Five types of malaria parasites can infect humans:

• Plasmodium (P.) falciparum
• P. vivax
• P. ovale
• P. malariae
• P. knowlesi

The five recent U.S. cases were caused by P. vivax, which is less likely to result in severe infections than P. falciparum. Prompt treatment is crucial, as severe infections of P. falciparum can lead to death.

Symptoms of malaria infection include fever, flu-like illness, shaking chills, headache, muscle aches, and tiredness. Nausea, vomiting, and diarrhea may also occur. Most individuals will experience symptoms 10 days to four weeks after infection, although in some cases, symptoms appear earlier or up to a year later.

Treatment for malaria usually involves the use of antimalarial drugs such as chloroquine phosphate and artemisinin-based combination therapies.

No malaria vaccine is approved by the U.S. Food and Drug Administration, but ongoing research offers promising possibilities.

The results of a randomized controlled trial published in December 2022 demonstrated the safety and efficacy of a three-dose regimen of a whole-parasite vaccine called Plasmodium falciparum sporozoite vaccine. The trial was conducted among adults living in Burkina Faso in West Africa, where malaria is endemic.

“Our study shows that the vaccine can be given to malaria-experienced adults in a highly endemic area and still provide protection,” Dr. Matthew B. Laurens, director of the International Clinical Trials Unit in the Malaria Research Group at the Center for Vaccine Development and the study’s corresponding author, said in a statement.