Dr. Anthony Fauci, the former director of the National Institute of Allergy and Infectious Diseases, was hospitalized with a case of West Nile virus and is now recovering at home, a spokesperson said.
Fauci is expected to make a full recovery, the spokesperson told ABC News in a statement.
West Nile virus is the leading cause of mosquito-borne disease in the continental United States, according to the Centers for Disease Control and Prevention.
Mosquitoes typically become infected with the virus after feeding on infected birds and then spread it to humans and other animals, according to the CDC. Cases typically begin rising in July and are highest in August and September, data from the agency shows.
Several health departments in the U.S. say they have detected West Nile virus in mosquito samples this year. At least 216 cases of West Nile virus have been detected in 33 states, the CDC reports in it's latest figures.
The majority of people with the virus do not have symptoms, but about one in five will experience fever along with headaches, body aches, joint pain, diarrhea, vomiting or a rash. Most symptoms disappear but weakness and fatigue may last for weeks or months.
Fauci retired in December 2022 as director of NIAID, a position he had held since 1984. During that time, Fauci advised seven presidents and guided the nation's response to infectious disease outbreaks including AIDS, Zika, Ebola and COVID-19.