A single dose of Covishield vaccine induced high neutralizing antibody and T cell responses - Sri Lankan study
July 30, 2021 03:55 pm
A study in Sri Lanka has found that 93.4% individuals developed antibodies to a single dose of the Covishield vaccine, the made-in-India variant of Oxford-AstraZeneca’s AZD-1222 formulation, while 97.1% developed neutralizing antibodies.
With the initiation of the COVID-19 vaccination program, Health Care Workers in Sri Lanka were the first to be vaccinated with Covishield vaccine.
Therefore, the Allergy, Immunology and Cell Biology Unit, Department of Immunology Molecular and Molecular Medicine investigated antibody responses to the SARS-CoV-2, neutralizing antibody responses, antibody responses to the variants, along with T cell responses.
The full article is available here at Nature Communications, which has an impact factor of 14.9: Immune responses to a single dose of the AZD1222/Covishield vaccine in health care workers | Nature Communications
93.4% individuals developed antibodies to a single dose of the vaccine and 97.1% developed neutralizing antibodies. There was no difference in immune responses in younger individuals compared to those >60 years of age.
The vaccine induced potent T cell responses with 67.1% developing T cell responses. However, the antibody responses to the beta SARS-CoV-2 virus variant was low. Antibodies to delta was not measured, as delta was not a problem during the time the study was conducted (February and March 2021).
The research team included scientists from the Allergy, Immunology and Cell Biology Unit, Department of Immunology Molecular and Molecular Medicine, Colombo Municipality Council and University of Oxford.
The funding for this study was provided by the World Health Organization, UK Medical Research Council and the Foreign and Commonwealth Office and the Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Science (CIFMS), China.
The group is also studying immune responses to other vaccines such as Sputnik, Moderna and Sinopharm and how the immunity to these different vaccine persist and compare with natural infection.
The most recent preprint on the immune responses to the Covishield vaccine at 16 weeks is available here: Immune responses to a single dose of the AZD1222/Covishield vaccine at 16 weeks in individuals in Sri Lanka | medRxiv