On Friday, August 18, the Maryland Department of Health reported a confirmed case of locally acquired malaria.  Most malaria cases diagnosed in the United States are imported, usually by persons who travel to countries where malaria occurs regularly.

However, locally acquired mosquito-transmitted malaria cases can occur, as  Anopheles  mosquito vectors exist throughout the United States.  Earlier this summer, Sarasota County, Florida reported seven cases,  and Cameron County, Texas reported one case of locally acquired malaria. Prior to this recent case, Maryland had not seen a case of malaria NOT related to travel in more than 40 years.  

According the the U.S. Centers for Disease Control and Prevention (CDC), more than 2,000 cases of malaria are reported annually in the United States,  with most cases occurring in people returning from international travel. Maryland typically reports around 200 travel-related malaria cases each year, and the Maryland Department of Health investigates each case for cause and risk. 

Malaria is a mosquito-borne disease caused by a parasite that commonly infects a certain type of mosquito which feeds on humans. Malaria can be dangerous if not treated, but early treatment is important.  

Symptoms of malaria usually appear seven to 30 days after a bite from an infected mosquito and can include:

• High fever
• Chills
• Body aches
• Diarrhea and vomiting

​The risk to the public for locally acquired mosquito-transmitted malaria remains very low, according to the CDC.  However, residents can take these precautions to prevent mosquito bites:

• Use insect repellent containing DEET on exposed skin.

• If weather and heat allow, wear loose-fitting, long sleeved clothing.

• Keep windows and doors closed or covered with screens to keep mosquitoes out of your house.

• Empty standing water at least once a week to prevent mosquitoes from laying eggs.

• Repair broken screening on windows, doors, porches, and patios. 

• Before you travel, learn about the health risks and precautions for malaria and other diseases for your destination.

• If you are planning to travel abroad, check with your health care provider for current recommendations on prescription medications to prevent malaria.

• If you have traveled to an area where malaria transmission occurs more often, and you develop fever, chills, headache, body aches, and fatigue, seek urgent medical care and tell your health care provider that you have traveled. 

Additional information on malaria is available at  CDC.gov/parasites/malaria.