National Weekly SARS-CoV-2 RT-PCR Screening of All Workers in Long-Term Care Facilities Associated with Decrease in Resident Mortality Rate.

INTRODUCTION: Outbreaks of COVID-19 in long-term care facilities (LTCFs) have resulted mainly from disease transmission by asymptomatic health care workers. This study examines whether routine screening tests carried out on health care workers can help in reducing COVID-19 outbreaks, morbidity, and mortality of LTCF residents. METHODS: The study followed a weekly, nationwide, government-funded screening program of LTCF personnel for SARS-CoV-2, by using reverse transcription polymerase chain reaction as the main testing technology. It included all residents and employees in Israeli LTCFs who were screened weekly during the second wave of COVID-19, during the period of time between July 13, 2020, and November 21, 2020. RESULTS: During the study period, 1,107 LTCFs were screened on a weekly basis, including 62,159 HCWs and 100,046 residents. The program screened a median of 55,282 (range 16,249, min 45,910, max 62,159) employees per week, 0.05-1.5% of which were positive for SARS-CoV-2. LTCF mortality in the first wave accounted for 45.3% of all COVID-19 deaths recorded nationally (252 of 556), and in the second wave, this ratio was reduced to 30.3% (709 of 2,337) representing a reduction of 33.8% in expected mortality (p < 0.001). A significant reduction was detected also in hospitalization rate (13.59 vs. 11.41%, p < 0.001) and elder (≥75 years old) mortality rate (52.89 vs. 41.42%, p < 0.001). 214 outbreaks in the second wave were avoided by early identification of SARS-CoV-2 positive HCWs and successful prevention of subsequent infections in the facility. CONCLUSION: Routine weekly SARS-CoV-2 RT-PCR testing of LTCF employees was associated with reduced national LTCF residents' hospitalizations and mortality rate.

Effectiveness of BNT162b2 mRNA Coronavirus Disease 2019 (COVID-19) Vaccine Against Acquisition of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Among Healthcare Workers in Long-Term Care Facilities: A Prospective Cohort Study.

BACKGROUND: We assessed vaccine effectiveness (VE) of BNT162b2 mRNA coronavirus disease 2019 (COVID-19) vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) acquisition among healthcare workers (HCWs) of long-term care facilities (LTCFs). METHODS: This prospective study, in the framework of the "Senior Shield" program in Israel, included routine weekly nasopharyngeal SARS-CoV-2 RT-PCR testing from all LTCF HCWs since July 2020. All residents and 75% of HCWs were immunized between December 2020 and January 2021. The analysis was limited to HCWs adhering to routine testing. Fully vaccinated (14+ days after second dose; n = 6960) and unvaccinated (n = 2202) HCWs were simultaneously followed until SARS-CoV-2 acquisition or end of follow-up, 11 April 2021. Hazard ratios (HRs) for vaccination versus no vaccination were calculated (Cox proportional hazards regression models, adjusting for sociodemographics and residential-area COVID-19 incidence). VE was calculated as (1- HR) × 100. RT-PCR cycle threshold (Ct) values were compared between vaccinated and unvaccinated HCWs. RESULTS: At >14 days post-second dose, 40 vaccinated HCWs acquired SARS-CoV-2 (median follow-up, 66 days; cumulative incidence, 0.6%) versus 84 unvaccinated HCWs (median follow-up, 43 days; cumulative incidence, 5.1%) (HR, .11; 95% CI, .07-.17; unadjusted VE, 89%; 95% CI, 83-93%). Adjusted VE >7 and >14 days post-second dose were similar. The median PCR Ct targeting the ORF1ab gene among 20 vaccinated and 40 unvaccinated HCWs was 32.0 versus 26.7, respectively (P value  = .008). CONCLUSIONS: VE following 2 doses of BNT162b2 against SARS-CoV-2 acquisition in LTCF HCWs was high. The lower viral loads among SARS-CoV-2-positive HCWs suggest further reduction in transmission.

Association of BNT162b2 Vaccine Third Dose Receipt With Incidence of SARS-CoV-2 Infection, COVID-19-Related Hospitalization, and Death Among Residents of Long-term Care Facilities, August to October 2021.

Importance: COVID-19 vaccine might be less immunogenic and effective among residents of long-term care facilities (LTCFs). Objective: To examine the association of BNT162b2 third dose (first booster dose) with overall SARS-CoV-2 infection, COVID-19 hospitalizations, and mortality among LTCF residents during a nationwide surge of the Delta variant in Israel. Design, Setting, and Participants: This observational cohort study conducted nationwide COVID-19 surveillance in LTCFs in Israel between August and October 2021. Participants were residents of LTCFs aged 60 years or older. Exposures: Vaccination with the third dose of BNT162b2 vaccine vs receipt of 2 doses at least 5 months earlier, based on self-preference and choice. Main Outcomes and Measures: The cumulative incidences of reverse transcription-polymerase chain reaction (RT-PCR)-confirmed SARS-CoV-2 infection, COVID-19 hospitalizations, and COVID-19-related deaths more than 7 days after vaccination with the third dose were compared between the groups using Kaplan-Meier curves. Hazard ratios (HRs) and 95% CIs were obtained using multivariable Cox regression models. Results: Among 18 611 residents included in the analysis, 12 715 (68.3%) were female, 463 (2.5%) were from the Arab population, 16 976 (91.2%) were from the general Jewish population, and 618 (3.3%) were from the ultraorthodox Jewish population; the mean (SD) age was 81.1 (9.2) years; 16 082 residents received their first booster dose (third dose) and 2529 were vaccinated with 2 doses at least 5 months earlier. The median (IQR) follow-up durations were 66 (60-70) days among 3-dose recipients and 56 (53-62) days among 2-dose-only recipients; 107 residents had SARS-CoV-2 infection after 7 days following vaccination with the booster dose compared with 185 among the 2-dose only group (cumulative incidence: 0.7% vs 7.5%; adjusted HR, 0.11 [95% CI, 0.07-0.15]). The respective adjusted HRs were 0.07 (95% CI, 0.03-0.14) and 0.10 (95% CI, 0.04-0.24) for the associations of vaccination with the third dose with hospitalization for mild-to-moderate COVID-19 and severe illness. Five COVID-19-related deaths occurred among the third dose vaccinees during the follow-up period compared with 22 among the 2-dose-only vaccinees (cumulative rate: 0.04% vs 0.9%; adjusted HR, 0.04 [95% CI, 0.009-0.16]). Conclusions and Relevance: This cohort study found significant inverse associations between vaccination with the third dose of the BNT162b2 vaccine with overall SARS-CoV-2 infection, COVID-19 hospitalizations, severe disease, and COVID-19-related deaths among LTCF residents during a massive surge caused by the Delta variant in Israel.

Association of Receipt of the Fourth BNT162b2 Dose With Omicron Infection and COVID-19 Hospitalizations Among Residents of Long-term Care Facilities.

Importance: The administration of a fourth BNT162b2 COVID-19 vaccine dose was approved in Israel in December 2021 for individuals 60 years or older who were vaccinated with a third dose 4 months previously or earlier to control the substantial surge of the SARS-CoV-2 Omicron variant. Nonetheless, the association between receipt of the fourth dose and protection against infection remains elusive. Objective: To determine the association of the fourth BNT162b2 dose with protection against SARS-CoV-2-related infections, hospitalizations, and deaths during the Omicron surge in long-term care facility (LTCF) residents. Design, Setting, and Participants: This prospective cohort study was conducted in Israel between January 10 and March 31, 2022 and included LTCF residents 60 years or older. Exposures: Vaccination with the fourth dose of BNT162b2 vs 3 doses that were administered 4 months previously or earlier. Main Outcomes and Measures: Cumulative incidences of SARS-CoV-2 infections, hospitalizations, and deaths during the Omicron surge. The follow-up was initiated more than 7 days after receipt of the fourth dose, which was matched to the follow-up initiation date of those who had received 3 doses of vaccine in each facility. We obtained hazard ratios and 95% confidence intervals from multivariable Cox regression models. Results: The data of 43 775 residents (mean [SD] age, 80.1 [9.4] years; 29 679 women [67.8%]) were analyzed, of whom 24 088 (55.0%) and 19 687 (45.0%) received the fourth and third dose (4 months previously or earlier), respectively. The median follow-up time was 73 days (4-dose group: IQR, 6 days; 3-dose group: IQR, 56 days). More than 7 days postvaccination with the fourth dose, SARS-CoV-2 infection was detected among 4058 fourth-dose vs 4370 third-dose recipients (cumulative incidence, 17.6% vs 24.9%). The corresponding incidences of hospitalizations for mild-to-moderate COVID-19, severe illness, and mortality were 0.9% and 2.8%, 0.5% and 1.5%, and 0.2% and 0.5%, respectively. The adjusted protections were 34% (95% CI, 30%-37%), 64% (95% CI, 56%-71%), and 67% (95% CI, 57%-75%) against overall infection, hospitalizations for mild-to-moderate illness, and severe illness, respectively, and 72% (95% CI, 57%-83%) against related deaths. Conclusions and Relevance: The results of this cohort study suggest that receipt of a fourth BNT162b2 dose conferred high protection against COVID-19 hospitalizations and deaths among LTCF residents during a substantial Omicron variant surge, but protection was modest against infection. These findings are relevant to the control of COVID-19 pandemic globally, especially among the population of LTCFs.

BNT162b2 mRNA COVID-19 (Comirnaty) Vaccine Effectiveness in Elderly Patients Who Live in Long-Term Care Facilities: A Nationwide Cohort.

INTRODUCTION: In early 2020, the novel SARS-CoV-2 virus began to spread around the world and claim victims. Initially, in the Western world, COVID-19-related mortality was due to illness in long-term care facilities (LTCFs). To manage the COVID-19 crisis in LTCFs in Israel, the Ministry of Health established a task force named "Senior Shield." The task force executed a screening program of weekly polymerase chain reaction (PCR) SARS-CoV-2 tests for LTCF residents and caregivers, and at a later stage, the task force led the Ministry of Health vaccination program at LTCFs. This study aimed to estimate the effectiveness of the BNT162b2 mRNA COVID-19 (Comirnaty) vaccine in reducing COVID-19 morbidity and mortality in LTCF residents. METHODS: We designed a nationwide cohort study utilizing data from the Senior Shield task force. Residents had received the vaccines starting December 2020. The study follow-up period was 5 months (ending May 2021). We defined four outcomes: (a) documented SARS-CoV-2 infection, defined by a positive PCR test, (b) COVID-19 death, defined by a positive PCR test followed by death, (c) all-cause mortality, defined as death regardless of the result of a PCR test, and (d) a composite endpoint which included documented SARS-CoV-2 infection or death, the earliest of both. We used Kaplan-Meier curves with a log-rank comparison and Cox regression with a time-dependent covariate model to estimate adjusted hazard ratios for vaccine effectiveness (VE). The index date was the date of the first vaccine dose. In unvaccinated residents, the index date was the first date of vaccination in their LTCF. RESULTS: A total of 43,596 residents with a mean age of 83 years living in 454 LTCFs were found eligible for this study. Ninety-one percent of the study population received the first vaccine dose (39,482) and 86% received the second vaccine dose (37,656). Estimated VE 28 days after the first vaccine dose (approximately 7 days after the second vaccine dose) was 81.2% for SARS-CoV-2 infection, 85.3% for COVID-related death, 63.7% for all-cause mortality, and 71.1% for the composite endpoint (SARS-CoV-2 infection or death). CONCLUSION: This study shows that the BNT162b2 mRNA COVID-19 vaccine effectively prevents SARS-CoV-2 infection, COVID-19-related death, and all-cause mortality in LTCF residents. Further research is warranted on the effect of the third vaccine (booster) in this population.