RESUMEN
The ongoing COVID-19 pandemic has hit long-term care facilities (LTCF), with outbreaks affecting both residents and health care workers (HCWs). Elderly persons have been prioritized in the implementation of vaccination programs. Here we investigated a COVID-19 outbreak, caused by the Beta variant (B.1.351) in a LTCF where residents and HCWs had received 2 doses of Comirnaty vaccine (Pfizer/BioNTech) until one month before the outbreak. Samples from 14 residents (SARS-CoV-2 PCR-negative: n = 8, PCR-positive: n = 6) and 10 HCWs (PCR-negative: n = 10) were collected at a median of 54 days following the second vaccine dose. IgG antibodies to SARS-CoV-2 spike glycoprotein and neutralizing antibody (NAb) titers were measured. Additionally, functional responses of PBMCs to SARS-CoV-2 spike and nucleocapsid proteins were investigated. We observed that Comirnaty induced higher IgG concentrations and NAb titers in HCWs compared to residents. PBMCs of HCWs responded vigorously to stimulation with SARS-CoV-2 spike glycoprotein, with the secretion of interferon gamma, granzyme B and perforin-1 into supernatants. In comparison, only 3 of 9 samples from residents showed positive cellular responses to spike glycoprotein. Group-level cellular responses directed at SARS-CoV-2 nucleoprotein remained low both in HCWs and in residents. Only 2 of 2 PCR-positive residents showed a positive response consistent with exposure to SARS-CoV-2 breakthrough infection. Our results show that elderly persons are at increased risk for breakthrough infection after vaccination. Weak vaccine-directed responses in the elderly need to be addressed in vaccination protocols.
RESUMEN
Introduction: Healthcare worker (HCW) compliance with infection prevention and control (IPC) measures plays a critical role in preventing COVID-19 transmission in healthcare settings. To ensure optimal adherence to COVID-19-specific IPC practices, there is a need to understand the factors that influencing them. Objectives: To identify and explain factors that influence the compliance to COVID-19 specific IPC measures among HCWs in LTCFs in Finland. Methods: The study included a web-based survey and a qualitative research study based on the Theoretical Domains Framework (TDF). The questions in the survey covered background information of the respondent and LTCF as well as behaviour factors. The link to the anonymous survey was distributed to the LTCFs through regional IPC experts and authorities. The outcome was modeled using both ordinary logistic regression and penalized ridge logistic regression using regrouped explanatory variables and original more correlated set of explanatory variables, respectively. The in-depth interviews were conducted by using a semi-structured guide. The subjects were recruited from those who participate in the survey. The interviews were conducted between January and February 2021. Data was analysed thematically using NVIVO12. Results: A total of 422 HCWs from 17/20 regions responded to the survey. The study findings suggested that three TDF domains influence the compliance with COVID19 specific IPC measures: environmental factors and resources (inadequate staffing), beliefs about capabilities and reinforcement (follow up and feedback of the management). The qualitative study included 20 HCWs consisting of nurses and assistant nurses who provided care in LTCFs during the pandemic. The study identified two themes that explain environmental factors and resources;lack of planning for emergency;changing work responsibilities. Beliefs in capabilities were linked with knowledge, resources and responsibilities, and reinforcement was linked with management absence and culture. Conclusion: This study provides insights into TDF domains that can be used to develop evidence-based behaviour change interventions to support HCW compliance with pandemic-specific IPC measures in LTCFs during future epidemics.