Iowa resident died of rare Lassa fever, officials say

CNN
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An eastern Iowa resident who recently traveled to West Africa died after contracting Lassa fever, state officials said Monday. The virus, which belongs to the same category of viral hemorrhagic fever as Ebola, is rare in the United States.

The Iowa Department of Health and Human Services announced the death Monday, but did not release the person's name and provided few details about them. Preliminary tests were presumed positive for the virus, and the U.S. Centers for Disease Control and Prevention is working to confirm the diagnosis.

The agency said the person was middle-aged and had traveled to West Africa, where he is believed to have contracted the virus.

The current risk of transmission in the United States is “incredibly low,” according to Iowa State Medical Director Dr. Robert Kruse.

According to the University of Minnesota's Center for Infectious Disease Research & Policy, about 100,000 to 300,000 people become infected with Lassa fever each year in West Africa, where the disease is endemic. Since 1969, there have only been eight known cases in the United States, all of which were travel-related.

It is even rarer for someone to die from Lassa fever. According to the World Health Organization, the overall mortality rate from the disease is just 1%.

In severe cases bleeding may occur; difficulty breathing; pain in chest, back and stomach; and vomiting.

Mild symptoms may include a mild fever, fatigue or headache. Most people infected with Lassa virus have no symptoms at all.

Lassa fever can be transmitted between people, but not through casual contact. Typically, the virus only spreads when someone comes into contact with the bodily fluids of an infected person.

In West Africa, Lassa fever is most commonly transmitted by multi-mouthed rats. People can become ill after touching objects contaminated with rat feces or urine or after eating contaminated food. According to the CDC, some people also become sick after eating the rats themselves.

In the case of Lassa fever, rapid treatment is crucial. Ribavirin, a broad-spectrum antiviral that works well against RNA viruses and is also used to treat hepatitis C, is the primary treatment.

Kruse said his department is investigating and monitoring the situation in collaboration with the CDC and local public health partners. Authorities are trying to determine who may have had close contact with the patient, who was being treated in isolation at the University of Iowa Health Care Medical Center.

According to the CDC, the patient was not ill during the trip, so the risk to other airline passengers is extremely low.