A comment by a WHO official on Monday calling such asymptomatic transmissions "very rare” touched off a furious scientific debate over the unresolved question and attracted widespread criticism of the organization.
Less than 24 hours later, the WHO convened a special news conference to walk back its comments. But the comment from Monday had already spread widely and been seized upon by conservatives and others to bolster arguments that people do not need to wear masks or maintain social distancing precautions.
Harvard's Global Health Institute wrote in a memo responding to the WHO's first comments that "all of the best evidence suggests that people without symptoms can and do readily spread SARS-CoV2."
