Chinese vaccine maker Sinovac Biotech plans to start a clinical trial of its experimental coronavirus vaccine with children and adolescents later this month, widening its test on a shot that’s already in the final stage of study with adults.

Finding a vaccine that works for the entire population, including younger people, could be crucial to preventing outbreaks of the virus — that has led to over 940,000 deaths worldwide — through schools and kindergartens, potentially affecting also teachers and parents.

A total of 552 healthy participants aged between three and 17 will take two doses of US-listed Sinovac's CoronaVac or a placebo in a combined Phase 1 and Phase 2 trial estimated to begin on Sept 28 in the northern Chinese province of Hebei, according to a registration record.