According to a recent study by researchers at the Centers for Disease Control and Prevention in the United States, more than half of Covid-19 infections are caused by presymptomatic and asymptomatic people.
Assessment of transmissions of SARS-CoV-2 in people without symptoms
Researchers from the Centers for Disease Control and Prevention (the main federal agency in the United States) wanted to assess the proportion of transmissions of SARS-CoV-2 in the community and especially in people without symptoms. Published in JAMA Open Network, the study reveals that people without symptoms are the cause of the majority of Covid-19 cases. According to the researchers, more than half of all transmissions of the virus are caused by presymptomatic people (who have not yet developed symptoms) as well as by asymptomatic people (who will never develop symptoms).
59% of infections due to asymptomatic people
According to researchers, 30% of people infected with Covid-19 never develop symptoms. Yet these asymptomatic individuals are 75% as infectious as those who develop symptoms. Another finding of scientists, 59% of all transmissions came from asymptomatic transmission, including 35% of presymptomatic individuals and 24% of individuals who never develop symptoms. This amounts to saying that more than 50% of new infections with SARS-CoV-2 have been estimated to be due to exposure to people who are infected but without symptoms.
Reduce the risk of transmission from people without symptoms
Based on the results, the study’s authors suggest that identifying and isolating symptomatic individuals alone is not sufficient to control the spread of SARS-CoV-2. In the results of the study, we can read as follows: In the absence of effective and widespread use of therapeutics or vaccines that can reduce or eliminate infectivity, successful control of SARS-CoV-2 cannot be based solely on identification and control. isolation of symptomatic cases; even if implemented effectively, this strategy would be insufficient. These results suggest that effective control also requires reducing the risk of transmission from infected people who do not show symptoms. Measures such as wearing masks and social distancing allow individuals to protect themselves and, if infected, reduce risks to their communities “.