WHO Says Asymptomatic Spread “Rare,” Sparking Debate

Maria Van Kerkhove

The WHO called into question the extent that asymptomatic people are spreading COVID-19, launching a global debate, The Hill reports.

"From the data we have, it still seems to be rare that an asymptomatic person actually transmits onward to a secondary individual," said Maria Van Kerkhove, the WHO’s technical lead for COVID-19, citing unpublished data from detailed contact tracing reports at a briefing yesterday. She suggested that the focus should be on following symptomatic cases.

If accurate, the implications would be huge—perhaps allowing some shutdown restrictions to ease. But if wrong, it could undo months of hard work, at a time people are chafing at the restrictions.

Already, shutdown critics are pouncing on the news on social media.

But Harvard Global Health Institute director Ashish Jha posited in a Twitter thread that the WHO could be using the term "asymptomatic," when it really means "presymptomatic,"—an important distinction. Jha suggests that the agency should be more clear in its messaging, and notes that some models "suggest 40-60% of spread is from people when they didn't have symptoms," Forbes reports.