TORONTO – A review of 61 studies and reports involving more than 1.8 million people suggests that at least one in three people infected with COVID-19 has no symptoms, according to a study published in the Annals of Internal Medicine.
The authors of Scripps Research in San Diego, California, reviewed global studies and reports published until November 17, 2020 – including two major surveys in England and Spain – that tested the presence of COVID-19 antibodies in more than one million people .
The researchers compiled 43 studies that used the PCR test and 18 studies that used the antibody test to cross their data.
The compiled data showed that at least a third of the individuals tested positive for the virus, but never experienced symptoms.
Data like this highlights the importance of testing asymptomatic people, said Dr. Brian Conway, Medical Director of the Vancouver Infectious Diseases Center, on CTV’s news channel on Saturday.
“If we identify groups of individuals for whom the transmission network is unclear, I think there is a role in testing a larger number of asymptomatic individuals to … stop these transmission networks more effectively,” said Conway.
It is a feeling that echoed in the study.
“In light of the data presented here, we believe that the control strategies for COVID-19 should be changed, taking into account the prevalence and risk of transmission of asymptomatic SARS-CoV-2 infection”, notes the study, adding that, as vaccines are launched globally “more research will be needed to determine their effectiveness in preventing asymptomatic infection”.