TORONTO – An analysis of 61 studies and reports of 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 through November 17, 2020 – including two large 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 PCR testing and 18 studies that used antibody testing to cross-check their data.
The data compiled showed that at least one third of people tested positive for the virus, but never showed symptoms.
Such data highlights the importance of testing for asymptomatic people, Vancouver Center for Infectious Diseases Medical Center Dr. Brian Conway told CTV 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 more asymptomatic individuals to … disrupt these transmission networks more effectively,” Conway said.
It is an echoing feeling in the study.
“Given the data presented here, we believe that COVID-19 control strategies need to be modified, taking into account the prevalence and risk of transmitting asymptomatic SARS-CoV-2 infection,” the study notes, adding that as vaccines are launched globally, “More research will be needed to determine their effectiveness in preventing asymptomatic infection.”