Lassa Fever Virus in Minnesota Traveler Coming from West Africa Confirmed

Lassa fever is a common viral fever in West Africa that is carried by rodents and easily transmitted from person to person. The Minnesota Department of Health has confirmed a case of Lassa fever in a traveler who came back from West Africa.

The man returned from West Africa on March 31 and went to see a doctor after he had a fever. Because of his travel history, his blood samples were sent to the U.S. Centers for Disease Control and Prevention, which turned out to be a very good decision because he tested positive for Lassa fever on April 3.

Although deaths from Lassa fever are rare, it is an acute viral illness that can spread through direct contact with sick persons. Approximately 5,000 people die from the virus each year in Africa, out of the estimated 100,000 to 300,000 cases. The last case of Lassa fever to be reported in the United States was back in 2010 in Pennsylvania, and only eight total cases have been documented in the U.S.

"This imported case is a reminder that we are all connected by international travel," said Dr. Tom Frieden, director of the U.S. Centers for Disease Control and Prevention, in this Minneapolis Star Tribune article. "A disease anywhere can appear anywhere else in the world within hours."

However, there is no public risk, as health officials are monitoring the case. The Minnesota Health Department as well as the CDC are working to notify everyone who may have come into contact with the infected traveler, especially those on the same flight. The traveler is in stable condition and the virus does not easily spread through casual contact, but health officials want to be sure and take every precaution possible.

It's important for those who may have come into contact with the traveler to get tested because Lassa fever symptoms do not occur until 1-3 weeks after infection. Symptoms include a slight fever, general malaise, and a headache. In some cases, symptoms can rapidly progress and include hemorrhaging (in gums, eyes, or nose), respiratory distress, constant vomiting, facial swelling, pains in chest, back, and/or abdomen, and shock.

More about the Lassa fever case in Minnesota is available on the CDC website.