We refer to Ms Lynn Tan Gek Lian's letter "Expiry date for 'fully vaccinated' status a matter of public interest" (Nov 10).

The Ministry of Health regularly reviews the evidence from studies in Singapore and abroad on the protection provided by the Covid-19 vaccines.

As these studies are ongoing, when enacting the regulations earlier, we had in the interim specified a duration of 365 days in the Infectious Diseases (Mass Gathering Testing for Coronavirus Disease 2019) Regulations 2021, to allow persons who have completed the primary series of their vaccinations to be exempted from vaccination-differentiated safe management measures.

While two doses of the mRNA vaccines provide excellent protection against severe disease, there will be waning protection against infection.

Hence the Ministry of Health recommends that all eligible vaccinated persons receive their booster doses to improve their protection against Covid-19 infection and reduce transmission.

This will also further increase protection against severe disease.

As more data becomes available, including on the increase in protection provided by booster doses, the Expert Committee on Covid-19 Vaccination will study the evidence and make its recommendations, and the Ministry of Health will review the stipulated timeframe.

Derrick Heng (Dr)

Deputy Director of Medical Services (Public Health Group)

Ministry of Health