Dr. Anthony Fauci said during an interview on Wednesday that a World Health Organization expert was “not correct” for stating that coronavirus infections from those who are asymptomatic are “very rare.”
Dr. Maria Van Kerkhove, a World Health Organization’s infectious disease expert, walked back her comments from Monday one day later, qualifying her statement by saying it’s not the official policy of the WHO.
"I used the phrase 'very rare.' I think that's misunderstanding to state that asymptomatic transmission globally is very rare. What I was referring to was a subset of studies," Van Kerkhove said during a press conference on Tuesday. "I was just trying to answer a question at a press conference, I wasn't stating a policy of the WHO or anything like that."
While the majority of coronavirus cases come from those who are symptomatic, Fauci said on ABC’s “Good Morning America” that the spread from those who are asymptomatic is not uncommon.
"The evidence that we have given the percentage of people, which is about 25, 45-percent of the totality of infected people, likely without symptoms," he said. "And we know from epidemiological studies that they can transmit to someone who is uninfected, even when they're without symptoms. So to make a statement to say that's a rare event was not correct."
On Monday, Dr. Ashish Jha, the director of Harvard's Global Health Institute, took issue with Van Kerkhove's anaylsis
"Asymptomatic spread is the Achilles heel of this outbreak," Jha tweeted. "Both asymptomatic and pre-symptomatic spread huge problem for controlling disease because folks shedding virus while asymptomatic pre-symptomatic has one advantage: You can use contact tracing to find folks they infected. But that doesn't help prevent pre-symptomatic spread"
Jha cited a May Swiss study that indicated that between 40 and 60% of all coronavirus cases originated from people when they didn't have symptoms at the time of the spread.
The debate comes as a number of states are continuing to see an increase in coronavirus cases. Most notably is Arizona, which has advised hospitals to be prepared to expand intensive care units in order to accommodate the influx of coronavirus patients.