Finding and isolating people with symptomatic COVID-19 alone will not control the ongoing spread of the coronavirus, new research results show. Because more than 59% of cases of transmission of the virus were from asymptomatic carriers. Therefore, it is worth isolating for all sick people.
SARS-CoV-2 is easily transmitted from person to person. Optimal control of COVID-19 depends on resources and mitigation measures that can prevent transmission, but the relative importance of such measures is disputed.
The researchers believed that peak infectivity occurred during the median time to symptom onset. According to statistics, 30% of those infected with coronavirus have no symptoms at all. Moreover, their infectivity is 75%, as in those who have symptoms.
Therefore, scientists initially thought that asymptomatic carriers of the coronavirus could infect others in 24% of cases of transmission. But it turned out that in fact, 59% of all cases of transmission of coronavirus occurred from asymptomatic carriers, of which 35% were from sick people, but with an asymptomatic course of the disease, and 24% were from people who could not even assume they had a coronavirus.
Wearing masks and social distancing empowers people to protect themselves and, if infected, reduce the risk to themselves and those around them. These measures can also be complemented by strategic testing of people who are not sick, for example, through contact tracing or at high risk of contamination of others (staff in the institution or people with frequent contact with people). To combat SARS-CoV-2, numerous measures are imperative that effectively reduce the risk of transmission in the absence of symptoms.
These results indicate that measures such as mask-wearing, hand hygiene, social distancing, and strategic testing of people who are not sick could be the basis for slowing the spread of COVID-19 until safe and effective vaccines are available and widely used.