TORONTO – A review of 61 studies and reports from more than 1.8 million people indicates 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.
Authors of Scripps Research in San Diego, California, reviewed global studies and reports published on 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 has.
The researchers compiled 43 studies that used PCR testing and 18 studies that used antibody testing to cross-reference their data.
The composite data showed that at least one-third of the individuals tested positive for the virus but never experienced symptoms.
Data like this emphasize the importance of testing asymptomatic people, said dr. Brian Conway, medical director of the Center for Infectious Diseases in Vancouver, told CTV’s News Channel.
“If we identify groups of individuals for whom the transmission network is unclear, I think there is a role to play in testing larger numbers of asymptomatic individuals to interrupt the transmission networks more effectively,” Conway said.
This is a sentiment that resonates in the study.
“Given the data presented here, we believe that COVID-19 control strategies need to change, taking into account the incidence and transmission risk of asymptomatic SARS-CoV-2 infection,” the study said, adding that As vaccines roll out worldwide, “more research is needed to determine their effectiveness in preventing asymptomatic infection.”