We thank Mr He Jinhe for his letter (“为何科兴疫苗不能作为追加剂”, 19 Nov).
There has not been sufficient studies done around the world on the effectiveness of the Sinovac-Coronavac vaccine as a booster after mRNA vaccines. On the other hand, an mRNA booster after two mRNA doses has been studied and has been shown to be highly effective, further reducing the risk of COVID-19 infection by around 70%, and the risk of severe infections by around 90%, as compared to those who have received only two doses of the mRNA vaccines.
The Ministry of Health (MOH) has therefore accepted the Expert Committee on COVID-19 Vaccination’s (EC19V) recommendations for all persons who have taken two doses of mRNA vaccines to be boosted with mRNA vaccines. The Sinovac-Coronavac vaccine is not offered for this purpose, unless one is medically ineligible to receive the mRNA vaccine.
EC19V will continue to monitor and review the use of COVID-19 vaccines in Singapore as more local and international data become available over time, and update our recommendations as necessary. We encourage all who are eligible to receive and complete their COVID-19 vaccination series, as well as booster doses, to protect themselves and their loved ones.
Associate Professor Benjamin Ong
Expert Committee on COVID-19 Vaccination