A man died from the rare African virus Lassa fever after returning to the United States from a trip to Liberia, CDC officials confirmed.
The man traveled from Liberia to Morocco to JFK International Airport on May 17.
He did not have a fever or symptoms when he left Liberia, and his temperature was shown to be normal when taken in the U.S.
The next day, the man went to a hospital in New Jersey with symptoms of a sore throat, fever, and tiredness. According to the hospital, he was asked about his travel history and he did not reveal his recent trip to West Africa.
He was sent home the same day, but returned to the hospital on May 21 when symptoms began to worsen. The man was later transferred to a second hospital prepared to treat viral hemorrhagic fevers.
Samples submitted to CDC tested positive for Lassa fever, but tests for Ebola and other viral similar diseases were negative.
The man was reported to be in isolation when he died Monday evening.
Lassa fever is not nearly as deadly as the Ebola virus, killing only one percent of those who are infected as compared to Ebola’s death rate of 70 percent.
In West Africa, there are about 100,000 to 300,000 cases of Lassa fever annually, and 5,000 deaths related to the Lassa fever virus.
Most commonly, the Lassa fever virus is carried by rodents and transmitted to humans through contact with waste of rodents that are infected. Lassa fever can also be transmitted from person to person through direct contact with blood or bodily fluids of an infected person, but only in rare cases.
The CDC is working with public health officials to track down anyone who may have had contact with the man and could potentially have contracted Lassa fever. Those found to have been in close contact will be monitored for symptoms of Lassa fever for 21 days.
The failure to immediately diagnose the Lassa fever virus by the hospital the man was treated at is being compared to the experience of Thomas Eric Duncan, the first person in the U.S. to die from Ebola.
Duncan was also released from the hospital after just one day, and he was not asked for his travel history. When he returned in a more dire condition, he could not be treated and later died from the disease.
He also became the first person to spread Ebola in the U.S., infecting nurses Nina Pham and Amber Vinson.
The likelihood of Lassa fever spreading in the U.S. is said to be very low, but Dr. Tom Frieden, head of the Center for Disease Control, told NPR that he wants to see a continued emphasis on controlling infections such as this one.
“That’s why it’s so important to strengthen our infection control in this country, and our efforts around the world to find, stop and prevent health threats from spreading.”
There have only been six reported cases of Lassa fever in the U.S. over the past 40 years, and it has never been spread from person to person during those six cases.
[Photo By Jessica McGowan/Getty Images]