Immune response elicited from heterologous SARS-CoV-2 vaccination: Sinovac (CoronaVac) followed by AstraZeneca (Vaxzevria)

Limited COVID-19 vaccines in many countries have delayed mass-immunization. Although individuals fully vaccinated with Vaxzevria (AstraZeneca) have higher antibody levels than those with CoronaVac (Sinovac), heterologous prime-boost with CoronaVac-Vaxzevria yielded comparable antibody levels to two-dose Vaxzevria. Combination use of different available vaccines may be warranted in Thailand, which faces limited vaccine choice and supply.