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Research on the ChAdOx1 nCoV-19, also known as the Oxford-AstraZeneca vaccine, indicates that a long interval between first and second doses does not compromise the immune response after a late second dose.

Needle and a vaccine vial

Additionally, a third dose of the vaccine continues to boost antibodies against SARS-CoV-2. The results were released in a preprint today.

COVID-19 vaccine supply shortages are causing concerns in some countries about compromised immunity as the interval between first and second dose extends due to limited vaccine availability. When examining the effects of a delay of up to 45 weeks between first and second doses in study participants, results demonstrated that antibody levels were increased after a delayed second dose. Additionally, a longer delay between first and second doses may be beneficial, resulting in an increased antibody titre and enhanced immune response after the second dose.

Read the full story on the University of Oxford website