Booster doses of current vaccines may not be enough: WHO

The World Health Organisation (WHO) has said that current Covid-19 vaccines may need to be updated if they are to provide continued protection against emerging variants, including Omicron.

WHO's Technical Advisory Group on Covid-19 Vaccine Composition (TAG-CO-VAC), a group of 18 experts, on Tuesday said that although current vaccines provide a high level of protection against severe disease and death caused by Variants Of Concern (VOC), future vaccines that can prevent infection and transmission need to be developed.

In the meantime, the composition of current Covid-19 vaccines may need to be updated in order to protect against the evolution of the virus, Xinhua news agency reported.

Such updates need to be based on strains that are genetically and antigenically close to the circulating variants. They should also elicit "broad, strong, and long-lasting" responses in order to "reduce the need for successive booster doses," WHO added.

The experts have encouraged Covid-19 vaccine manufacturers to provide data on the performance of current and Omicron-specific vaccines, to help decide when changes to vaccine composition may be required.

Regarding the current Omicron variant, the experts emphasised the importance of wider global access to current Covid-19 vaccines.