More Malaria Coming to the USA

Although malaria was eliminated in the United States in the mid-1950s, malaria cases continue to be imported from endemic regions, reported the Centers for Disease Control and Prevention (CDC).

In a Morbidity and Mortality Weekly Report published on October 13, 2023, the CDC confirmed that locally acquired mosquito-transmitted cases have been identified in the U.S.. In mid--2023, locally-acquired malaria cases (Plasmodium vivax) were identified in Arkansas, Florida, Maryland, and Texas. In these states, each person was infected near an imported malaria case.

This transmission route was confirmed because malaria-infected Anopheles mosquitoes can exist in many areas in the U.S.

These malaria cases underscore common challenges in malaria diagnosis. According to the CDC, malaria is a curable disease caused by four species of protozoan parasites of the genus Plasmodium.

Proposed interventions include ensuring that travelers to regions where malaria is endemic take appropriate malaria chemoprophylaxis to reduce personal and community risk.

Furthermore, according to recent malaria outbreak reports, the U.S. should be prepared to identify additional malaria cases in 2023.

To the south, the Pan American Health Organization estimated on September 7, 2023, that approximately 41 million people are living in areas where the risk of infection by mosquito-carrying malaria is considered moderate to high in twenty-one.

Moreover, the disease-carrying mosquitoes are expanding their impact.

A study published by the Royal Society in February 2023 indicated these mosquitoes gained an average of 6.5 meters of elevation, and their geographic ranges moved south of the equator by 4.7 kilometers per year. 

Across the Atlantic Ocean, the World Health Organization says four African countries account for over 50% of all malaria deaths worldwide, led by Nigeria with 31%).

African countries recently received good news when the Mosquirix™ (RTS,S/AS01) and the R21/Matrix-M™ malaria vaccines obtained expanded recommendations and funding to provide greater access to these innovative vaccines.

As of mid-October, these malaria vaccines are not available in the U.S.

The CDC continues publishing Travel Health Alerts notifying international travelers of their potential exposure to malaria and other diseases, such as dengue and polio.