SARS-CoV-2 seroprevalence among nursing home residents and staff in Belgium, SCOPE

From February 1st until March 24th, 2021, the SCOPE study measured the proportion of residents and
staff members in Belgian nursing homes (NH) that had anti-SARS-CoV-2 antibodies (seroprevalence).
In total, 1,572 residents and 1,253 staff members from 69 NHs in Belgium were tested for the presence
of SARS-CoV-2 antibodies by a point-of-care rapid test, and responded to a COVID-19 related
questionnaire. At the first testing moment (five bimonthly follow-up testing moments are scheduled), we
observed the following:Between February 1st and March 24th, 2021, during the ongoing SARS-CoV-2
vaccination campaign, 69% (95% CI: 63%-74%) of residents and 80% (95% CI: 76%-
83%) of staff in Belgian nursing homes had anti-SARS-CoV-2 antibodies.
At the time of testing 96% of the residents received at least one vaccination dose and
68% were fully vaccinated. For staff this data were respectively 85% and 48%. So,
although more residents than staff were vaccinated at the moment of testing,
seroprevalence was lower among residents than among staff.
At least one day after receiving one dose of a COVID-19 vaccination, 52% of residents
tested positive for anti-SARS-CoV-2 antibodies and 77% tested positive at least one day
after receiving two doses. Among staff these findings were higher, being respectively
75% and 98%.
The proportion of residents and staff with antibodies after vaccination was higher among
those who reported a previous SARS-CoV-2 infection than among those without a self-
reported previous infection.