BACKGROUND: Hybrid SARS-CoV-2 immunity may provide longer duration protection against severe SARS-CoV-2 infection and hospitalisation than purely vaccine-derived immunity. Older adults represent a high-risk group for severe disease, yet available data is skewed towards younger adults.
METHODS: A prospective longitudinal study at a large London long-term care facility (LTCF) was conducted from March 2020 to April 2022 to assess the effect of hybrid versus vaccine-only immunity on SARS-CoV-2 infection in older adults during Omicron variant dominance. Hybrid immunity was assessed by a combination of SARS-CoV-2 polymerase chain reaction testing weekly (asymptomatic screening) and as required (symptomatic testing), as well as serial SARS-CoV-2 serology.
RESULTS: 280 participants (median age 82 yrs, IQR 76-88 yrs; 95.4% male) were followed up. 168/280 (60%) had evidence of hybrid immunity prior to the Omicron variant wave. Participants with hybrid immunity had substantially lower odds of acquiring COVID-19 infection during the Omicron wave compared to those with vaccine-only immunity (unadjusted odds ratio 0.26, 95% CI 0.14-0.47, chi-squared P < .0001). Participants with hybrid immunity had an odds ratio of 0.40 (0.19-0.79) for asymptomatic infection and 0.15 (0.06-0.34) for symptomatic infection (Likelihood ratio test, P < .0001).
CONCLUSIONS: Our data highlight potential opportunities to target ongoing booster vaccination campaigns for those most at risk of severe infection. Reporting of data in older adults will be of particular value to examine the effect of hybrid immunity as new variants continue to emerge and vaccination strategies evolve.

India is presently undergoing a rapid demographic transition and experiencing a gradual increase in an ageing population. As a result, the households were continuously exposed to catastrophic economic impacts, ultimately influencing the healthcare utilisation of older people. The study examined the gender differentials in the choice of in-patient private and public hospitalisation among Indian elderly using Andersen\'s Health Behaviour Model. The database was acquired from the nationally representative cross-sectional survey (NSSO, 2017-18). Bivariate chi-square and binomial logistic regression techniques were used to fulfill the objective. In addition, the poor-rich ratio and concentration index was used to understand the inherent socioeconomic inequalities in healthcare preferences. The findings suggest that aged men were 27 percent more prone to avail private healthcare facilities than aged women. Further, older adults, who are married, belong to the upper caste, have higher education and gone through surgery, and primarily reside in an affluent society were more likely to prefer private in-patient hospitalisation. It represents negligence of older women in access to better healthcare who had financial strain and economically dependent. The study can be used to reframe existing public health policies and programs, particularly focusing on the older women, to avail cost-effective treatment.