COVID-19 vaccines have been shown to reduce mortality and complications due to SARS-COV-2. However, question remain about the necessity of a booster shot, let alone a second booster. In Singapore, only elderly above 80 and those who are medical vulnerable have been recommended to take their second booster shot. What does age have to do with vaccine response? Also, why do we need a booster in the first place?
In this Nature Communication paper, A/Prof Paul MacAry was part of a Singapore cohort study with colleagues from A*STAR Singapore Immunology Network and A*STAR Infectious Diseases Labs – ID Labs with clinicians from Tan Tock Seng Hospital, Alexandra Hospital, Singapore, JurongHealth Campus and National University Hospital. The study led by A/Prof Lisa F.P. Ng and Prof Laurent Renia showed that the 30% of study participants showed a decrease in their immunity against COVID after 6 months of vaccination. In addition, individuals older than 60 years old took longer to mount a vaccine response compared to younger individuals, with sustained immunity at around 6 months. The third dose of the vaccine was able to strongly boost the low immunity in older adults especially against the original COVID strain, Delta and Omicron variants.
