(The Hill) — The Maryland Department of Health has reported its first locally acquired malaria case in more than four decades. 

State officials said late last week that a Maryland resident tested positive for malaria despite not having traveled outside of the United States or to another U.S. state with recent malaria cases. 

“Malaria was once common in the United States, including in Maryland, but we have not seen a case in Maryland that was not related to travel in over 40 years,” Department of Health Secretary Laura Herrera Scott said in a statement. “We are taking this very seriously and will work with local and federal health officials to investigate this case.” 

The Maryland resident was hospitalized and is now recovering, the health department said. 

David Blythe, director of the department’s Infectious Disease and Epidemiology and Outbreak Response Bureau, said the patient went to a hospital due to a fever and sweating, NBC Washington reported. Blythe reportedly said the patient may have been bitten by a mosquito that previously bit someone who had traveled. 

Last month, the Centers for Disease Control and Prevention (CDC) issued a health advisory over the spread of a few locally acquired malaria cases in Florida and Texas, which marked the first locally acquired infections in the U.S. in 20 years. Blythe told reporters the strain in the Maryland patient is different than the one found in Florida and Texas, NBC News reported. 

Malaria is a mosquito-borne disease caused by a parasite that usually leads to fever, chills and flu-like illness, according to the CDC. The agency considers malaria a “medical emergency” that can be fatal, specifically among children under 5 and pregnant women. Symptoms can range from mild to life-threatening and can also include an enlarged spleen, enlarged liver or mild jaundice.

The CDC said around 2,000 causes of malaria are diagnosed each year, with the “vast majority,” being reported in travelers and immigrants coming from countries with regular malaria transmission. 

Once very common in the U.S., malaria’s endemic disease status ended after the National Malaria Eradication Program in the 1940s and ’50s.