About four in 10 COVID cases are asymptomatic, making them potential sources of increased transmission of the infectious disease, according to a study.

They conducted a systematic review and meta-analysis of 95 unique studies with 29,776,306 individuals undergoing testing

The findings, published in the JAMA Network Open, showed that the asymptomatic infections were 0.25 percent among the tested population and 40.50 percent among the population with confirmed COVID-19.

The study found that the percentage of asymptomatic infections among the confirmed population was 54.11 percent in pregnant women and 52.91 per cent in air or cruise travellers. The percentage was 47.53 percent in nursing home residents or staff.

In addition, the study also showed that the percentage of asymptomatic infections was higher among groups younger than 39 years than in other age groups, possibly because the young adults were more likely to show only mild or moderate clinical symptoms.

This indicated that young adults who often presented mild or no symptoms were a potential source of transmission in the community.

"Screening for asymptomatic infection is required, especially for countries and regions that have successfully controlled SARS-CoV-2. Asymptomatic infections should be under management similar to that for confirmed infections, including isolating and contact tracing," Ma said.

(This story was published from a syndicated feed. Only the headline and picture has been edited by FIT.)