We refer to the article, “Most people in S’pore well protected against severe Covid-19: Expert” (Jan 16)

In general, vaccinated persons who have minimum protection, such as three doses of mRNA vaccine, continue to have good protection against severe disease and hospitalisation with the current Covid-19 variants.

However, for persons aged 60 years and above and the medically vulnerable, who face greater risk of severe Covid-19, there is good international and local data that a fourth dose of an mRNA vaccine further reduces the risk of severe Covid-19 substantially.

As with all vaccines, the protection conferred by Covid-19 vaccination will wane with time. New Covid-19 variants from the Omicron family also continue to emerge. The updated bivalent vaccines generate a broader and stronger immune response compared with the original vaccine, especially against the Omicron variants.

Vaccination continues to be our primary defence against Covid-19, and we encourage eligible individuals to keep up to date with their vaccination, to better protect against the risk of severe disease ahead of waning immunity, and to achieve broader and better protection against future variants.

The Ministry of Health and the Expert Committee on Covid-19 Vaccination will continue to monitor the evolving situation and global studies on vaccine effectiveness against the various Covid-19 variants.

Derrick Heng (Dr)

Deputy Director of Medical Services (Public Health Group)

Ministry of Health