News Scan for Sep 14, 2022

COVID boosters restored antibody levels in nursing home residents, staffSARS-CoV-2 antibodies fell over time after vaccination or COVID-19 infection but were restored with booster doses in West Virginia nursing home residents and staff, and antibody levels were significantly lower during the Delta than the Omicron variant surges in those with breakthrough infections, finds a study published yesterday in JAMA Network Open.A team led by West Virginia University researchers obtained blood samples from 1,086 vaccinated residents and 1,053 vaccinated employees at 41 West Virginia nursing homes from Sep 13 to Nov 30, 2021, a period that spanned both Delta and Omicron predominance.Age range was 18 to 103 years, 78% were women, 96% were White, and all had received either two doses of the Pfizer/BioNTech or Moderna COVID-19 vaccines or one dose of the Johnson & Johnson version.Thirty-four percent of residents and 22% of staff reported previous COVID-19 infections, and 6% of residents and 5% of staff reported previous vaccine-breakthrough infections, 82% of which occurred during Delta, from August to October 2021.

Ten percent of the total cohort had breakthrough infections from Jan 22, 2021, to Jan 16, 2022, with 90% occurring from August 2021 to January 2022.A total of 101 participants had breakthrough infections from October 2021 to January 2022, of whom 44% had received a booster dose before infection.

Sixty-five infections occurred amid Omicron in January 2022; of them, 54% occurred in residents, 69% of whom had received a booster, compared with 3% of staff, 37% of whom were booster recipients.Antibody levels fell over time after vaccination or infection but rebounded after a booster dose, with a particularly strong response