Despite the unfortunate incident, authorities emphasize that the risk of further transmission within the state remains minimal.

Robert Kruse, the state medical director of the Iowa Department of Health and Human Services, reassured the public through a statement posted on the department's website. "I want to assure Iowans that the risk of transmission is incredibly low in our state. We continue to investigate and monitor this situation and are implementing the necessary public health protocols," he said.

The individual who passed away was described as a middle-aged resident from eastern Iowa and was treated at University of Iowa Health Care. Specific details regarding the duration of care or if the person sought prior medical attention were not disclosed.

While person-to-person transmission of Lassa virus is rare, it can occur in healthcare settings, particularly if healthcare providers are unaware they are dealing with an infected patient and fail to take appropriate precautions. This situation underscores the importance of early detection and proper protective measures.

Historically, Lassa fever cases imported into the United States are uncommon, with only eight known instances in the past 55 years, including this latest case. Previous cases include two fatalities in New Jersey in 2004 and 2015 and a recovered case in Minnesota in 2014.

Lassa fever predominantly exists in West African countries such as Nigeria, Ghana, Guinea, Sierra Leone, and Liberia, causing around several hundred thousand infections and approximately 5,000 deaths annually. The multimammate rat is the primary reservoir for the virus, transmitting it to humans through direct contact, consumption of infected rodents, or contamination of food and household items with rodent excrement.

Armand Sprecher, a viral hemorrhagic fever expert at Doctors Without Borders, emphasized that although severe Lassa fever presents with symptoms similar to Ebola, it does not lead to extensive human-to-human transmission. "You don't see a lot of human-to-human transmission," Sprecher noted. "Most people get it from the source, the reservoir."

According to the World Health Organization, about 80% of those infected with Lassa virus exhibit no or only mild symptoms such as headache, fatigue, and low-grade fever. Severe cases can result in bleeding, difficulty breathing, vomiting, and shock, with a fatality rate of about 15%. However, some areas report significantly higher mortality rates; for instance, Sierra Leone sees fatality rates as high as 70% among severe cases, as noted by Robert Garry, a professor at Tulane Medical School.

Garry also highlighted that person-to-person transmission, though rare, does occur, particularly in hospital settings even in West Africa. "It happens in West Africa, even in places where they're very aware of the possibility [of Lassa cases]. So, yeah, if you were not expecting a disease like that to show up in your hospital, it could happen," he explained.

Despite the potential for transmission, Garry expressed confidence that further spread is unlikely. "There's very little chance that this is going to spread beyond that hospital setting. But they have to do the case contacts [investigations] and all that to make sure," he said. Among the diseases that cause viral hemorrhagic fevers, Lassa fever is the one most frequently imported to non-endemic countries.