The United States has recorded its first case of malaria in over two decades after five people became sick with the mosquito-borne parasite. The infected persons did not have any recent international travel history.
The Center for Disease Control and Prevention in a health alert, warned doctors to be on the lookout for malaria cases after people who had not traveled outside of the country fell ill with malaria in Texas and Florida.
Four cases were recorded in Florida’s Sarasota County and one in Texas’ Cameron County, located at the state’s far eastern border with Mexico.
The CDC says they don’t think that the cases in Florida and Texas are linked, but they are the first cases of local transmission in the United States since 2003.
The CDC also said that all five cases were of the P. vivax malaria strain. This is “good news,” Jackie Cook, an associate professor of malaria epidemiology at the London School of Hygiene & Tropical Medicine said, “because the strain is less likely to cause severe or fatal infections than other strains.”
However, P. vivax can cause relapsing malaria infections as the parasites hide in the liver and reemerge months or even years later, she said. “So, you do need to get a bit of extra treatment if you have a vivax infection to make sure you don’t get those relapsing episodes.”
The US typically saw around 2,000 malaria cases from people coming in from other countries each year, with about 300 of them becoming severe and five to 10 deaths. The United States and 42 other countries and territories have been certified as malaria-free by the WHO.
According to the World Health Organization, about 247 million cases of malaria and 619,000 deaths were reported worldwide in 2021.
It is thought that the malaria cases reported in Florida and Texas, as well as other indigenous cases, might have roots in other malaria-endemic countries.
How Is Malaria Caused & Spread
Malaria is caused and transmitted by the bites of female mosquitoes of the Anopheles genus. Malaria is spread when a female Anopheles mosquito, infected with a protozoan parasite of the Plasmodium genus, bites and infects a human.
A clean mosquito can become a career when it bites the now-infected human. Malaria is thus spread further as the mosquito bites other people.
Malaria can also be transmitted through infected blood during transfusions or organ transplants, for instance, or by a pregnant mother to her fetus.
Symptoms of malaria begin to show about 10-15 days after infection. However, it can start appearing in some people much earlier or later, even one year after infection, according to the CDC.
They include fever, chills, headaches, muscle aches, fatigue, nausea, and vomiting. In severe cases, people can experience unusual bleeding, jaundice, and difficulty breathing.
How To Safeguard Yourself Against Malaria & Mosquitoes
People living in mosquito-prone areas are advised to always sleep with a mosquito net covering their beds, and screens on their doors or windows.
While outdoors, people can wear mosquito repellant and clothing that covers exposed parts of their bodies such as arms and legs.
Insecticides can be used indoors to kill mosquitoes while antimalarial medicines such as atovaquone or doxycycline that can be taken to reduce the risk of malaria infection.
Currently, there is no vaccine to permanently prevent malaria, however, research is ongoing to develop one.