Just 24 hours after claiming that asymptomatic spread of the novel coronavirus is “very rare,” the World Health Organization (W.H.O.) reversed course.
Dr. Maria Van Kerkhove, head of W.H.O.’s emerging diseases and zoonosis unit, explained that the spread of the global coronavirus pandemic is extremely unlikely:
From the data we have, it still seems to be rare that an asymptomatic person actually transmits onward to a secondary individual. It’s very rare. … We have a number of reports from countries who are doing very detailed contact tracing. They’re following asymptomatic cases. They’re following contacts. And they’re not finding secondary transmission onward. It’s very rare.
But on Tuesday, Kerkhove walked her statement back. “We don’t actually have that answer yet. There are some estimates that suggest that anywhere between 6% of the population and 41% of the population may be infected but not have symptoms within a point estimate of around 16%,” she said during a live Q&A streamed to social media.
“The majority of transmission is from people who have symptoms and are spreading it through infectious droplets,” she continued. “But there are a subset of people who don’t develop symptoms. To truly understand how many people don’t have symptoms, we don’t actually have that answer yet.”
WHO emergencies program executive director Dr. Mike Ryan said Kerkhove’s prior comments may have been “misinterpreted, or maybe we didn’t use the most elegant words to explain that.”