Key messages:
- The majority of HDSS residents with anti-spike IgG antibodies appear to have developed them as a result of natural infection, as only 11% - 27% of study participants reported receiving one or more doses of COVID-19 vaccine by May 2022.
- The proportion of HDSS residents with anti-spike IgG antibod- ies was significantly higher in Nairobi, an urban setting, than in rural Kilifi.
- Seroprevalence by May 2022 represents a substantial increase from May 2021 when about 20% of the residents within the Kilifi HDSS and 40% within the Nairobi Urban HDSS had an- ti-spike IgG antibodies.
- Surveillance for COVID-19 antibodies among residents of HDSS sites provides an opportunity to understand the extent COVID-19 spread and immunity within the general population in Kenya.