The spread of COVID-19 by patients who do not have symptoms is “very rare,” World Health Organization doctors said on Monday.
“We have a number of reports from countries who are doing very detailed contact tracing,” she added. “They’re following asymptomatic cases. They’re following contacts. And they’re not finding secondary transmission onward. It’s very rare.”
She added that government responses should focus on people who have symptoms—including isolating them, and tracing down people who they may have come into contact with.
The latest comments from the WHO suggests that asymptomatic spread is not the main way the CCP virus is being transmitted, and may in part assuage concerns that asymptomatic patients could be among the key drivers of the global spread of the virus.
It appears that Van Kerkhove was referring to asymptomatic cases only—where individuals never show symptoms—and not presymptomatic cases—where individuals don’t show symptoms at the time of being tested for the CCP virus, but develop symptoms later.
Van Kerkhove acknowledged that additional research is necessary to determine the prevalence of asymptomatic spread and how infectious asymptomatic patients are.
The CDC notes that while anyone can experience mild to sever symptoms, those who are older and those with severe underlying medical conditions, such as heart or lung disease or diabetes, “seem to be at higher risk for developing more serious complications from COVID-19 illness.”
The majority of U.S. states had implemented lockdown and stay-at-home orders in March, largely to curb the spread of the CCP virus by mobile presymptomatic and asymptomatic COVID-19 patients, or those who remain in the community with mild symptoms.
The CDC in early April cited the “potential for presymptomatic transmission” as something that “underscores the importance of social distancing, including the avoidance of congregate settings” in reducing the spread of COVID-19.