The impact of SARS-CoV-2 vaccines on antibody responses in the general population in the United Kingdom
Wei J., Stoesser N., Matthews P., Studley R., Bell I., Bell J., Newton J., Farrar J., Diamond I., Rourke E., Howarth A., Marsden B., Hoosdally S., Jones Y., Stuart D., W .Crook D., Peto T., Pouwels K., Eyre D., Walker S., COVID-19 Infection Survey team None.
Real-world data on antibody response post-vaccination in the general population are limited. 45,965 adults in the UK’s national COVID-19 Infection Survey receiving Pfizer-BioNTech or Oxford-AstraZeneca vaccines had 111,360 anti-spike IgG measurements. Without prior infection, seroconversion rates and quantitative antibody levels post single dose were lower in older individuals, especially >60y. Two doses achieved high responses across all ages, particularly increasing seroconversion in older people, to similar levels to those achieved after prior infection followed by a single dose. Antibody levels rose more slowly and to lower levels with Oxford-AstraZeneca vs Pfizer-BioNTech, but waned following a single Pfizer-BioNTech dose. Latent class models identified four responder phenotypes: older people, males, and those having long-term health conditions were more commonly ‘low responders’. Where supplies are limited, vaccines should be prioritised for those not previously infected, and second doses to individuals >60y. Further data on the relationship between vaccine-mediated protection and antibody responses are needed.