An internal email obtained by the Associated Press revealed 65 World Health Organization (WHO) staffers have been infected with the coronavirus.
The United Nations health agency is investigating how and where the staffers at its base headquarters contracted the virus despite safety measures such as PPE and social distancing.
World Health Organization chief Tedros Adhanom Ghebreyesus (pictured) self-quarantined after being identified as a contact of a person who tested positive for Covid-19.
"To my knowledge, the cluster being investigated is the first evidence of potential transmission on the site of WHO," Dr. Michael Ryan told reporters on Monday after the AP released a report on the email.
According to the AP the email said about half of those infected worked from home. But 32 of the infected staffers worked on the premises at The W.H.O. headquarters building in Geneva, Switzerland.
The CDC reported last month that 88% of Covid-19 positive tests were people who always wore masks.
Researchers quietly withdrew a study on the effectiveness of face masks after Covid-19 positive tests surged in places where face masks are mandated.
"The authors have withdrawn this manuscript because there are increased rates of SARS- CoV-2 cases in the areas that we originally analyzed in this study," the researchers wrote.
The study was funded in part by Yale University.