Safety and immunogenicity of CoronaVac and ChAdOx1 heterologous prime-boost vaccines in an overweight population in Chiang Mai, Thailand.

Background: In early 2021, the Ministry of Public Health of Thailand announced heterologous regimens for COVID-19 vaccines using CoronaVac as the first dose followed by ChAdOx1 nCoV-19 at 3 weeks apart. Priority was given to individuals above 60 years old and those who had seven underlying conditions, including obesity. The vaccine regimen was evaluated for safety and immunogenicity in overweight populations in Chiang Mai, Thailand.