Anthony Fauci, the face of the US government’s response to the Covid pandemic, is recovering at home after being hospitalised with West Nile virus.
The immunologist and former chief medical adviser to the president was hospitalised with the mosquito-borne disease around 11 days ago and had fever, chills and fatigue.
He left hospital earlier in the week and is expected to make a full recovery, the BBC’s US media partner CBS reports.
Dr Fauci, 83, told CBS that he likely contracted the virus from a mosquito bite in his garden.
Most people infected with West Nile virus do not feel sick, but around one in five develop symptoms, according to the Centers for Disease Control and Prevention (CDC), the US public health agency.
The virus spreads to humans when mosquitoes bite infected birds and then subsequently bite humans, the CDC says.
There is currently no vaccine for virus. It can be fatal in rare cases.
Dr Fauci, the former director of the National Institute of Allergy and Infectious Diseases, retired from public service in 2022.
He has previously said that he and his family receive death threats and now require round-the-clock security.
He has faced criticism from some over his handling of the Covid pandemic.
The leading immunologist was hauled in front of Congress earlier in the year by Republican politicians over accusations he attempted to obscure indirect US funding of the Wuhan Institute of Virology, the lab in China some believe could be linked to the emergence of Covid-19.
Dr Fauci described the allegations as false, and said they were politically motivated due to his public disagreements with former President Donald Trump at the height of the pandemic.