The World Health Organization (WHO) created confusion this week when it reported that “asymptomatic patients rarely spread the disease”. Currently, the best evidence suggests that people without symptoms can and do readily spread the virus that causes Covid-19. In fact, some evidence suggests that people may be most infectious in the days before they become symptomatic — that is, in the presymptomatic phase when they feel well, have no symptoms, but may be shedding substantial amounts of virus. The biggest take home message is people not showing symptoms can spread the virus, whether they ultimately feel sick or not. That’s why wearing masks and keeping distance are so important to limiting transmission.

Wear a Mask in Public