What to know about Lassa fever after Iowa resident dies of rare disease

An Iowa resident has died after contracting a suspected case of Lassa fever, health officials said.

The patient was diagnosed Tuesday after returning to the United States from West Africa earlier this month, according to the Centers for Disease Control and Prevention (CDC) and the Iowa Department of Health and Human Services (IDHHS).

The patient was admitted to isolation at the University of Iowa Health Care Medical Center in Iowa City and died Tuesday afternoon, according to officials.

Health officials said the risk to the public from the disease is low and that cases are typically found only in West Africa.

Here’s what you need to know about Lassa fever, how it’s spread and how it’s treated:

What is Lassa fever?

Lassa fever is “an acute viral hemorrhagic disease caused by the Lassa virus,” according to the World Health Organization.

“Lassa fever is a potentially life-threatening viral disease,” says Dr. Albert Ko, the Raj and Indra Nooyi Professor of Public Health at the Yale School of Public Health, told ABC News. “The virus, which is in this class of family called arenaviruses, is harbored by rats and rats specifically in the western part of Africa.”

The virus is primarily spread by multimamma rats belonging to the genus Mastomys, according to CDC.

Only multimamma rats in West African countries – such as Guinea, Liberia, Nigeria and Sierra Leone – are known to carry the virus. But people living in neighboring countries are also at risk of being infected with Lassa virus.

The first documented case was identified in 1969 in Lassa, Nigeria, which gave the disease its name, the CDC said.

In the past 55 years, there have been only eight travel-related cases of Lassa fever in the United States, according to the IDHHSmaking its American occurrence very rare.

How is Lassa fever spread?

Lassa fever is often spread by contact with urine or excrement from contaminated rats. Multimamma rats often live in areas where food supplies are stored. Such contact can occur by touching contaminated objects, eating contaminated food, getting the virus in an open cut or wound, eating infected rodents, or breathing air contaminated with infected urine or feces, such as by cleaning or sweeping, the CDC said.

Lassa fever can also be spread from person to person by coming into contact with the blood or body fluids of an infected person or by sexual contact.

“It’s not airborne. It’s not like COVID,” said Dr. Robert Murphy, professor of infectious diseases at Northwestern University Feinberg School of Medicine, to ABC News. “(Lassa fever), it has to be a liquid… So you don’t have to worry about being in the same room with somebody, but you have to be concerned if you’ve touched that person or have been with that person that do. and be exposed to any liquid they have.”

What are the symptoms of Lassa fever?

Lassa fever symptoms typically appear one to three weeks after a person is first infected, according to the CDC.

About eight out of 10 people who get Lassa fever have mild symptoms, including low-grade fever, fatigue, weakness and headache, or experience no symptoms at all and are never diagnosed, the CDC said. The remaining 20% ​​will experience severe symptoms that may include bleeding, facial swelling and vomiting, as well as chest, back and abdominal pain, difficulty breathing and shock.

Complications can include hearing loss and acute kidney failure, the experts said. If a pregnant person is infected, there is a high risk of miscarriage, with about 95% of fetuses not surviving, according to the CDC.

Less than 1% of people who get Lassa fever die. But of those who become seriously ill and are hospitalized, the mortality rate is about 15%.

“Once they get really sick, death is pretty quick. It’s usually within seven to 14 days,” Murphy said.

He added that diagnosing Lassa fever can be challenging because testing for the virus is not routine. The people who handle samples need to be careful if they come in contact with it and become infected, Murphy said.

How is Lassa fever treated?

Patients who are ill with Lassa fever may be given an antiviral drug called Ribavirin. It is most successful when given to the patient soon after they become ill and show symptoms, according to CDC.

Supportive care, including rest, hydration, and treatment of the symptoms of the virus, is also recommended.

Tips for preventing Lassa fever

There are currently no vaccines to prevent becoming infected with Lassa virus.

If anyone travels to West Africa, that is The CDC says the primary method of preventing infection with Lassa fever is to stay away from rats.

The CDC further recommends storing food in rat-proof containers and keeping one’s home clean. One should also avoid eating rats, and should catch and dispose of any rats in and around homes.

That said, most Americans don’t need to be concerned about Lassa fever, said Dr. Cow from the Yale School of Public Health.

“This is a disease that is really a major public health problem, but it is localized to West Africa,” he said. “It’s not a disease that spreads easily from one place to another, unlike some of the other diseases we’ve faced, like Zika and COVID, and that’s because people usually aren’t contagious until they start to develop symptoms and a lot of times we can screen and know people who are sick, you know, identify them and isolate them before they start traveling.”