The U.S. Centers for Disease Control and Prevention issued a health alert on Monday after four cases of malaria were detected in Florida and one in Texas.
Infectious disease specialist Dr. Aileen Marty explained how the disease functions and how to avoid it.
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>The five cases found are the first in 20 years to have been acquired within the U.S.
"The type of malaria that we're seeing here in Florida right now is [plasmodium] vivax malaria," said Dr. Marty. "And that's the same type of malaria that was transmitted just recently in Texas, also."
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>Plasmodium vivax is not considered as "serious" as plasmodium falciparum, a similar type of parasite that causes malaria, but for people who are already at an increased health risk, it can be, she said.
People with other underlying diseases, pregnant women, and young children are especially at risk, Dr. Marty said.
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"These Anopheles mosquitoes don't fly that far away from where they hatch," she explained. It's important to take preventative measures, but people who live outside of the regions where malaria was detected are not at as high of a risk.
The symptoms of the type of malaria that was spotted in Florida and Texas can vary.
"One of the things that vivax malaria is known for is causing a rupture of the spleen," she said. "And that can be instantly deadly."
Other symptoms include intermittent fever, headaches, fatigue, nausea, vomiting, diarrhea, anemia, jaundice, and more. If not treated, kidney failure and mental confusion can occur, Dr. Marty explained.
People can also experience vivax malaria repeatedly, due to hypnozoites, which are "sleeping" versions of the vivax parasite. Hypnozoites can stay in the liver and essentially wake up and begin to reinfect the blood cells, she said.
Certain drugs are used to treat the presence of hypnozoites, but people of African origin have a higher tendency to lack the G6PD enzyme, which makes it harder for the drugs to work, Dr. Marty said.
The disease is spread by Anopheles mosquitoes, which "tend to bite at dawn and dusk," Dr. Marty said.
Other types of mosquitoes, which can spread diseases like dengue, Zika, and chikungunya, can bite throughout the day, so it's important to wear a mosquito repellent approved by the EPA, she added. Be wary of standing water as well, as mosquitoes lay eggs in it.
"This is not something that we can take lightly, and people need to understand that it's here," Dr. Marty said.