Long-term effects of SARS-CoV-2 vaccination in the nursing home setting

Impact of a COVID-19 Outbreak in an Elderly Care Home after Primary Vaccination

Elderly care home residents are particularly vulnerable to COVID-19 due to immune-senescence, pre-existing medical conditions, and the risk of transmission from staff and visitors. This study aimed to describe the outcomes of a COVID-19 outbreak in a long-term care facility for elderly persons following the initial vaccination. A single-center, retrospective, observational design was used to analyze the variables associated with hospitalization and death rate by logistic regression. Adjusted odds ratios (aOR) and their 95% confidence intervals (CI) were calculated. Sixty-eight residents received the first dose of the COVID-19 vaccine. Despite being negative six days after vaccination, the performance of a second test 4 days later revealed 51 positives (75.0%) among residents and 18 among workers (56.3%). A total of 65 of the 68 residents (95.58%) had positive results with symptoms, whereas 34.9% required hospitalization, and 25.8% died. The best-fitting model to explain the distribution of cases reflects three points at the time of infection.. The time from vaccination to symptom onset explains the hospitalization and mortality rates since a day elapsed halves the risk of hospitalization (aOR = 0.57; CI = 0.38-0.75) and the risk of death by a quarter (aOR = 0.74; CI = 0.63-0.88). Nursing homes present an elevated risk of transmission and severity of SARS-CoV-2 infection. Although vaccination reduces the risk of hospitalization and death, extreme prevention and control measures are essential in these institutions despite the high vaccination coverage.

Resident Factors Associated With Breakthrough SARS-CoV-2 Infections

OBJECTIVE

To examine incidence of and resident characteristics associated with breakthrough infections (BTIs) and severe illness among residents with 2 messenger RNA (mRNA) vaccinations.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

Nursing home (NH) residents who completed their primary series of mRNA COVID-19 vaccination by March 31, 2021.

METHODS

Electronic health records and Minimum Data Set assessments from a multistate NH data consortium were used to identify BTI and severe illness (a composite measure of hospitalization and/or death within 30 days of BTI) occurring prior to November 24, 2021. A t test for differences in means was used to compare covariates for residents with and without BTI. Finally, we estimated incidence rate ratios (IRRs) for BTI with 95% CIs using a modified Poisson regression approach, comparing residents with BTI vs residents without. We adjusted for facility fixed effects in our model.

RESULTS

Our sample included 23,172 residents from 984 NHs who were at least 14 days past their second mRNA vaccine dose. Of those, 1173 (5%) developed an incident COVID-19 BTI (mean follow-up time: 250 days). Among residents with BTI, 8.6% were hospitalized or died within 30 days of BTI diagnosis. Factors associated with severe illness included age ≥85 years (IRR 2.08, 95% CI 1.08-4.02, reference age <65 years), bowel incontinence (IRR 1.73, 95% CI 1.01-2.99), coronary artery disease (IRR 1.96, 95% CI 1.31-2.94), chronic kidney disease (IRR 1.65, 95% CI 1.07-2.54), and schizophrenia (IRR 2.38, 95% CI 1.19-4.75).

CONCLUSIONS AND IMPLICATIONS

Among vaccinated NH residents, BTIs and associated severe illness are rare. Residents aged ≥85 years and with certain comorbidities appear to be the most vulnerable. Given that the pandemic continues and testing policies have relaxed, these data provide prognostic information for NH facilities faced with continued outbreaks.

The Impact of Vaccination on COVID-19 Burden of Disease in the Adult and Elderly Population: A Systematic Review of Italian Evidence

COVID-19 is a major global health threat, with millions of confirmed cases and deaths worldwide. Containment and mitigation strategies, including vaccination, have been implemented to reduce transmission and protect the population. We conducted two systematic reviews to collect nonrandomized studies investigating the effects of vaccination on COVID-19-related complications and deaths in the Italian population. We considered studies conducted in Italian settings and written in English that contained data on the effects of vaccination on COVID-19-related mortality and complications. We excluded studies that pertained to the pediatric population. In total, we included 10 unique studies in our two systematic reviews. The results showed that fully vaccinated individuals had a lower risk of death, severe symptoms, and hospitalization compared to unvaccinated individuals. The review also looked at the impact of vaccination on post-COVID-19 syndrome, the effectiveness of booster doses in older individuals, and nationwide adverse events. Our work highlights the crucial role that vaccination campaigns have played in reducing the burden of COVID-19 disease in the Italian adult population, positively impacting the pandemic trajectory in Italy.

Immunity in SARS-CoV-2 Infection: Clarity or Mystery? A Broader Perspective in the Third Year of a Worldwide Pandemic

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its mechanisms have been thoroughly studied by researchers all over the world with the hope of finding answers that may aid the discovery of new treatment options or effective means of prevention. Still, over 2 years into the pandemic that is an immense burden on health care and economic systems, there seem to be more questions than answers. The character and multitude of immune responses elicited in coronavirus disease 2019 (COVID-19) vary from uncontrollable activation of the inflammatory system, causing extensive tissue damage and consequently leading to severe or even fatal disease, to mild or asymptomatic infections in the majority of patients, resulting in the unpredictability of the current pandemic. The aim of the study was to systematize the available data regarding the immune response to SARS-CoV-2, to provide some clarification among the abundance of the knowledge available. The review contains concise and current information on the most significant immune reactions to COVID-19, including components of both innate and adaptive immunity, with an additional focus on utilizing humoral and cellular responses as effective diagnostic tools. Moreover, the authors discussed the present state of knowledge on SARS-CoV-2 vaccines and their efficacy in cases of immunodeficiency.

Multimorbidity and Frailty Are the Key Characteristics of Patients Hospitalized with COVID-19 Breakthrough Infection during Delta Variant Predominance in Italy: A Retrospective Study

The aims of this study were to describe the characteristics of patients hospitalized with delta SARS-CoV-2 breakthrough infection, and to identify factors associated with pneumonia on chest Computed Tomography (CT) and mortality. The clinical records of 229 patients (105 F), with a median age of 81 (interquartile range, IQR, 73−88) years old, hospitalized between June and December 2021 after completion of the primary vaccination cycle, were retrospectively analyzed, retrieving data on comorbidities, Clinical Frailty Scale (CFS), clinical presentation and outcomes. Multimorbidity (91.7% with ≥2 chronic illnesses) and frailty (61.6% with CFS ≥ 5) were highly prevalent. CFS (OR 0.678, 95% CI 0.573−0.803, p < 0.001) and hypertension were independently associated with interstitial pneumonia. Mortality was 25.1% and unrelated with age. PaO2/FiO2 on blood gas analysis performed upon admission (OR 0.986, 95% CI 0.977−0.996, p = 0.005), and CFS (OR 1.723, 95% CI 1.152−2.576, p = 0.008) were independently associated with mortality only in subjects < 85 years old. Conversely, serum PCT levels were associated with mortality in subjects ≥ 85 years old (OR 3.088, 95% CI 1.389−6.8628, p = 0.006). In conclusion, hospitalization for COVID-19 breakthrough infection mainly involved geriatric patients, with those aged ≥ 85 more characterized by decompensation of baseline comorbidities rather than typical COVID-19 respiratory symptoms.