COVID-19: Fiocruz study analyzes the influence of age on vaccine effectiveness

A study conducted by Brazilian researchers shows how age influences the effectiveness of the two main immunizers used in the country against COVID-19.

Submitted as a preprint in MedRxiv, the study  Influence of age on effectiveness and duration of protection in the Oxford/AstraZeneca and CoronaVac vaccines involved more than 75 million immunized people, becoming the largest study conducted with the two immunizers and may serve as a basis for guiding public health decisions, including the need for additional doses or booster doses.

Coordinated by Manoel Barral-Netto, a researcher at Fiocruz Bahia, the study evaluated the immunizers effectiveness in 75,919,840 people vaccinated in Brazil between January 18 and July 24 this year. The results show that both vaccines are effective in protecting against infection, hospitalization and death, considering the complete vaccination scheme (two doses): AstraZeneca (LSE: AZN)/Fiocruz, with 90% protection, and CoronaVac (developed by China’s Sinovac Biotech) with 75%. The research also showed that both Vaxzevria and CoronaVac accines offer protection against moderate and severe cases against the variants of concern circulating in Brazil during the analysis period.