The World Health Organisation's Chief scientist Soumya Swaminathan has warned against mixing and matching coronavirus vaccines, referring to it as a dangerous trend.

Chief scientist told an online briefing that it is a little bit of a dangerous trend. We are in a data-free, evidence-free zone as far as mix and match,"

It will be a chaotic situation in countries if citizens start deciding when and who will be taking a second, a third and a fourth dose.

A study conducted in the United Kingdom earlier found that adopting a mix-and-match approach to COVID-19 vaccines gives a more robust immune response.