Is the BNT162b2 COVID-19 vaccine effective in elderly populations? Results from population data from Bavaria, Germany

COVID-19 vaccine updates for people under different conditions

SARS-CoV-2 has caused global waves of infection since December 2019 and continues to persist today. The emergence of SARS-CoV-2 variants with strong immune evasion capabilities has compromised the effectiveness of existing vaccines against breakthrough infections. Therefore, it is important to determine the best utilization strategies for different demographic groups given the variety of vaccine options available. In this review, we will discuss the protective efficacy of vaccines during different stages of the epidemic and emphasize the importance of timely updates to target prevalent variants, which can significantly improve immune protection. While it is recognized that vaccine effectiveness may be lower in certain populations such as the elderly, individuals with chronic comorbidities (e.g., diabetes with poor blood glucose control, those on maintenance dialysis), or those who are immunocompromised compared to the general population, administering multiple doses can result in a strong protective immune response that outweighs potential risks. However, caution should be exercised when considering vaccines that might trigger an intense immune response in populations prone to inflammatory flare or other complications. In conclusion, individuals with special conditions require enhanced and more effective immunization strategies to prevent infection or reinfection, as well as to avoid the potential development of long COVID.

Comparison of fatalities due to COVID-19 and other nonexternal causes during the first five pandemic waves : Results from multiple cause of death statistics in Bavaria

BACKGROUND

Older age is a risk factor for a fatal course of SARS-CoV‑2 infection, possibly due to comorbidities whose exact role in this context, however, is not yet well understood. In this paper, the characteristics and comorbidities of persons who had died of COVID-19 in Bavaria by July 2022 are shown and compared with the characteristics of other fatalities during the pandemic.

METHODS

Based on data from multiple cause of death statistics, odds ratios for dying from COVID-19 (compared to dying from other nonexternal causes of death) were calculated by using logistic regression models, stratified by age, sex, and pandemic waves.

RESULTS

In Bavaria, a total of 24,479 persons (6.5% of all deaths) officially died from COVID-19 between March 2020 and July 2022. In addition to increasing age and male sex, preexisting diseases and comorbidities such as obesity, degenerative diseases of the nervous system, dementia, renal insufficiency, chronic lower respiratory diseases, and diabetes mellitus were significantly associated with COVID-19-related deaths. Dementia was mainly associated with increased COVID-19 mortality during the first and second waves, while obesity was strongly associated during the fourth wave.

DISCUSSION

The frequency of specific comorbidities in COVID-19 deaths varied over the course of the pandemic. This suggests that wave-specific results also need to be interpreted against the background of circulating virus variants, changing immunisation levels, and nonpharmaceutical interventions in place at the time.

Risk factors for the in‑hospital and 1‑year mortality of elderly patients hospitalized due to COVID‑19‑related pneumonia

Coronavirus disease 2019 (COVID-19) is characterized by poor outcomes and a high mortality rate, particularly among elderly patients. Since the beginning of the pandemic, an older age has been recognized as a critical risk factor for disease severity, with increasing mortality rates in each decade of life. This phenomenon may be a consequence of a poor previous health status, with a higher prevalence of pre-existing comorbidities and a higher degree of frailty. The majority of studies on the outcomes and risk factors of elderly patients refer to the first waves of the pandemic and the predictors of in-hospital mortality in these patients. The aim of the present study was to provide a detailed description of the clinical characteristics and management of a cohort of elderly patients (≥65 years of age) who were hospitalized with COVID-19-related pneumonia in all phases of the pandemic, presenting their outcomes, and investigating predictors of in-hospital and out-of-hospital mortality over a period of 1 year in this particularly vulnerable population. A total of 1,124 elderly patients (603 males, 53.7%) with a mean age of 78.51±7.42 years and a median Charlson comorbidity index (CCI) of 5 were included in the study. Of these patients, 104 (9.3%) were hospitalized during the period of prevalence of the original strain Wuhan, 385 (34.3%) were hospitalized during the period of prevalence of the Alpha variant, 221 (19.7%) were hospitalized during the period of prevalence of the Delta variant, and 414 (36.8%) were hospitalized during the period of prevalence of the Omicron variant. Overall, the in-hospital mortality rate was 33.4% (375 patients), and the 1-year mortality rate was 44.7% (502 patients). The majority of patients had not been vaccinated or had not completed full vaccination against severe acute respiratory syndrome coronavirus-2 (843 patients, 75%), given the period of infection. Age, immature granulocytes, lactate dehydrogenase (LDH) levels, ferritin levels, chest X-ray score, as well as the absence of full vaccination, cough and fatigue, were statistically significantly and independently associated with in-hospital mortality, while age, LDH levels, ferritin levels, alanine aminotransferase levels, CCI, chest X-ray score, the absence of cough and fatigue, and a history of dementia were statistically significantly and independently associated with 1-year mortality. On the whole, the present study demonstrates that both the in-hospital mortality and 1-year mortality rates of elderly patients hospitalized due to COVID-19-related pneumonia are high.

Predictors of COVID‑19‑associated mortality among hospitalized elderly patients with dementia

The mortality of elderly patients with dementia hospitalized with coronavirus disease 2019 (COVID-19)-associated pneumonia is high. The mortality rate of these patients continues to be high following their discharge. However, data on the outcomes of these patients in all phases of the pandemic are limited. The aim of the present study was to examine the clinical characteristics and the in-hospital and 90-day mortality rates of elderly patients with dementia hospitalized due to COVID-19-associated pneumonia during all phases of the pandemic. During the time period between February 15, 2021 to July 15, 2022, 105 elderly patients (≥65 years old) with dementia of various etiologies were hospitalized due to COVID-19-associated pneumonia. The patient characteristics and in-hospital outcomes within 90 days of admission were recorded. The mean age of the patients was 84.03±7.61 years and 60 (57.1%) patients were females. A total of 52 (49.5%) patients were hospitalized during the omicron variant period, 27 (25.7%) were fully vaccinated (three doses) and 38 (36.2%) patients succumbed during their hospitalization. In total, 52 (49.5%) patients succumbed within the first 90 days of admission. According to the univariate regression analysis, the omicron variant [hazard ratio (HR), 2.126; 95% confidence interval (CI), 1.073-4.213; P=0.031] and the absence of full vaccination (HR, 6.231; 95% CI, 1.500-25.87; P=0.012) were associated with a higher in-hospital mortality. In the multivariate regression analysis, only the absence of complete vaccination was an independent predictor of mortality (HR, 5.182; 95% CI, 1.205-22.28; P=0.027). According to the univariate regression analysis, age (HR, 1.045; 95% CI, 1.006-1.085; P=0.023) and the lack of complete vaccination (HR, 3.254; 95% CI, 1.294-8.181; P=0.012) were associated with 90-day mortality; in addition, by multivariate regression analysis, age (HR, 1.047; 95% CI, 1.007-1.048; P=0.021) and the absence of full vaccination (HR, 3.286; 95% CI, 1.307-8.265; P=0.011) exhibited an independent association with the 90-day mortality rate. Based on the findings presented herein, the in-hospital and 90-day mortality rates of elderly patients with dementia and COVID-19-associated pneumonia is high. An older age and the lack of complete vaccination are independently associated with poor outcomes.

Is Dementia Associated with COVID-19 Mortality? A Multicenter Retrospective Cohort Study Conducted in 50 Hospitals in Germany

BACKGROUND

Dementia has been identified as a major predictor of mortality associated with COVID-19.

OBJECTIVE

The objective of this study was to investigate the association between dementia and mortality in COVID-19 inpatients in Germany across a longer interval during the pandemic.

METHODS

This retrospective study was based on anonymized data from 50 hospitals in Germany and included patients with a confirmed COVID-19 diagnosis hospitalized between March 11, 2020 and July, 20, 2022. The main outcome of the study was the association of mortality during inpatient stays with dementia diagnosis, which was studied using multivariable logistic regression adjusted for age, sex, and comorbidities as well as univariate logistic regression for matched pairs.

RESULTS

Of 28,311 patients diagnosed with COVID-19, 11.3% had a diagnosis of dementia. Prior to matching, 26.5% of dementia patients and 11.5% of non-dementia patients died; the difference decreased to 26.5% of dementia versus 21.7% of non-dementia patients within the matched pairs (n = 3,317). This corresponded to an increase in the risk of death associated with dementia (OR = 1.33; 95% CI: 1.16-1.46) in the univariate regression conducted for matched pairs.

CONCLUSION

Although dementia was associated with COVID-19 mortality, the association was weaker than in previously published studies. Further studies are needed to better understand whether and how pre-existing neuropsychiatric conditions such as dementia may impact the course and outcome of COVID-19.

Epidemiological and Serological Analysis of a SARS-CoV-2 Outbreak in a Nursing Home: Impact of SARS-CoV-2 Vaccination and Enhanced Neutralizing Immunity Following Breakthrough Infection

Background: Despite a vaccination rate of 82.0% (n = 123/150), a SARS-CoV-2 (Alpha) outbreak with 64.7% (n = 97/150) confirmed infections occurred in a nursing home in Bavaria, Germany. Objective: the aim of this retrospective cohort study was to examine the effects of the Corminaty vaccine in a real-life outbreak situation and to obtain insights into the antibody response to both vaccination and breakthrough infection. Methods: the antibody status of 106 fully vaccinated individuals (54/106 breakthrough infections) and epidemiological data on all 150 residents and facility staff were evaluated. Results: SARS-CoV-2 infections (positive RT-qPCR) were detected in 56.9% (n = 70/123) of fully vaccinated, compared to 100% (n = 27/27) of incompletely or non-vaccinated individuals. The proportion of hospitalized and deceased was 4.1% (n = 5/123) among fully vaccinated and therewith lower compared to 18.5% (n = 5/27) hospitalized and 11.1% (n = 3/27) deceased among incompletely or non-vaccinated. Ct values were significantly lower in incompletely or non-vaccinated (p = 0.02). Neutralizing antibodies were detected in 99.1% (n = 105/106) of serum samples with significantly higher values (p < 0.001) being measured post-breakthrough infection. α-N-antibodies were detected in 37.7% of PCR positive but not in PCR negative individuals. Conclusion: Altogether, our data indicate that SARS-CoV-2 vaccination does provide protection against infection, severe disease progression and death with regards to the Alpha variant. Nonetheless, it also shows that infection and transmission are possible despite full vaccination. It further indicates that breakthrough infections can significantly enhance α-S- and neutralizing antibody responses, indicating a possible benefit from booster vaccinations.

Area Deprivation and COVID-19 Incidence and Mortality in Bavaria, Germany: A Bayesian Geographical Analysis

Background

Area deprivation has been shown to be associated with various adverse health outcomes including communicable as well as non-communicable diseases. Our objective was to assess potential associations between area deprivation and COVID-19 standardized incidence and mortality ratios in Bavaria over a period of nearly 2 years. Bavaria is the federal state with the highest infection dynamics in Germany and demographically comparable to several other European countries.

Methods

In this retrospective, observational ecological study, we estimated the strength of associations between area deprivation and standardized COVID-19 incidence and mortality ratios (SIR and SMR) in Bavaria, Germany. We used official SARS-CoV-2 reporting data aggregated in monthly periods between March 1, 2020 and December 31, 2021. Area deprivation was assessed using the quintiles of the 2015 version of the Bavarian Index of Multiple Deprivation (BIMD 2015) at district level, analyzing the overall index as well as its single domains.

Results

Deprived districts showed higher SIR and SMR than less deprived districts. Aggregated over the whole period, the SIR increased by 1.04 (95% confidence interval (95% CI): 1.01 to 1.07, p = 0.002), and the SMR by 1.11 (95% CI: 1.07 to 1.16, p < 0.001) per BIMD quintile. This represents a maximum difference of 41% between districts in the most and least deprived quintiles in the SIR and 110% in the SMR. Looking at individual months revealed clear linear association between the BIMD quintiles and the SIR and SMR in the first, second and last quarter of 2021. In the summers of 2020 and 2021, infection activity was low.

Conclusions

In more deprived areas in Bavaria, Germany, higher incidence and mortality ratios were observed during the COVID-19 pandemic with particularly strong associations during infection waves 3 and 4 in 2020/2021. Only high infection levels reveal the effect of risk factors and socioeconomic inequalities. There may be confounding between the highly deprived areas and border regions in the north and east of Bavaria, making the relationship between area deprivation and infection burden more complex. Vaccination appeared to balance incidence and mortality rates between the most and least deprived districts. Vaccination makes an important contribution to health equality.

Impact of COVID-19 immunisation on COVID-19 incidence, hospitalisations, and deaths by age group in Germany from December 2020 to October 2021

BACKGROUND

Utilising national surveillance data, we investigated the impact of the COVID-19 immunisation campaign on COVID-19 morbidity and mortality between December/2020 and October/2021 in Germany.

METHODS

We compared patterns in immunisation coverage, incidence, hospitalisations, and deaths among 12-17, 18-59, and 60+ year-olds and examined these patterns within the context of anti-pandemic measures.

RESULTS

COVID-19 incidence increased in all age groups following the end of lockdown restrictions in March/2021, but as Germany experienced successive peaks in incidence, age groups with higher immunisation coverage experienced successively smaller peaks. Notwithstanding corresponding increases during periods of higher incidence, among those aged 60+ years, COVID-19 related hospitalisations and deaths declined considerably as immunisation coverage increased, despite circulation of virus variants known to cause more severe illness.

CONCLUSION

Although ecological in nature, this study allows us to demonstrate clear patterns of decline in COVID-19 morbidity and mortality in Germany during the course of the immunisation campaign.

Roadmap for Sex-Responsive Influenza and COVID-19 Vaccine Research in Older Adults

Sex differences in the immune system are dynamic throughout the lifespan and contribute to heterogeneity in the risk of infectious diseases and the response to vaccination in older adults. The importance of the intersection between sex and age in immunity to viral respiratory diseases is clearly demonstrated by the increased prevalence and severity of influenza and COVID-19 in older males compared to older females. Despite sex and age biases in the epidemiology and clinical manifestations of disease, these host factors are often ignored in vaccine research. Here, we review sex differences in the immunogenicity, effectiveness, and safety of the influenza and COVID-19 vaccines in older adults and the impact of sex-specific effects of age-related factors, including chronological age, frailty, and the presence of comorbidities. While a female bias in immunity to influenza vaccines has been consistently reported, understanding of sex differences in the response to COVID-19 vaccines in older adults is incomplete due to small sample sizes and failure to disaggregate clinical trial data by both sex and age. For both vaccines, a major gap in the literature is apparent, whereby very few studies investigate sex-specific effects of aging, frailty, or multimorbidity. By providing a roadmap for sex-responsive vaccine research, beyond influenza and COVID-19, we can leverage the heterogeneity in immunity among older adults to provide better protection against vaccine-preventable diseases.

Effectiveness of BNT162b2, mRNA-1273, and ChAdOx1-S vaccines against severe covid-19 outcomes in a nationwide mass vaccination setting: cohort study

Objective

To estimate the effectiveness of the three covid-19 vaccines by Pfizer-BioNTech (BNT162b2), Moderna (mRNA-1273), and Oxford-AstraZeneca (ChAdOx1-S) in people after receiving two doses.

Design

Cohort study.

Setting

Nationwide, population based data in France, from the French National Health Data System (Système National des Données de Santé), between 27 December 2020 and 30 April 2021.

Participants

Adults aged ≥50 years receiving a first dose of BNT162b2, mRNA-1273, or ChAdOx1-S were randomly selected (1:1) and matched on the date of vaccination with one unvaccinated control. Individuals were matched on year of birth, sex, region of residence, and residence in a nursing home (for individuals aged ≥75 years). All individuals were followed up until 20 August 2021.

Main outcome measures

Primary outcome measure was vaccine effectiveness estimated at least 14 days after the second dose against covid-19 related hospital admission using Cox proportional hazards models adjusted for baseline characteristics and comorbidities. Vaccine effectiveness against covid-19 related death in hospital was also investigated.

Results

11 256 832 vaccinated individuals were included in the study (63.6% (n=7 161 658) with the BNT162b2 vaccine, 7.6% (n=856 599) with the mRNA-1273 vaccine, and 28.8% (n=3 238 575) with the ChAdOx1-S vaccine), along with 11 256 832 matched unvaccinated controls. During follow-up (up to 20 August 2021), 43 158 covid-19 related hospital admissions and 7957 covid-19 related deaths in hospital were registered. Compared with unvaccinated controls, vaccine effectiveness of two doses against covid-19 related hospital admission was 91% (95% confidence interval 91% to 92%), 95% (93% to 96%), and 91% (89% to 94%) for the BNT162b2, mRNA-1273, and ChAdOx1-S vaccines, respectively. Similar results were observed for vaccine effectiveness of two doses against covid-19 related deaths in hospital (BNT162b2, 91% (90% to 93%); mRNA-1273, 96% (92% to 98%); and ChAdOx1 nCoV-19, 88% (68% to 95%)). At 5-6 months after receiving the second dose of vaccine, effectiveness remained high at 94% (92% to 95%) for the BNT162b2 vaccine and 98% (93% to 100%) for the mRNA-1273 vaccine. Vaccine effectiveness of ChAdOx1-S estimated at 3-4 months was 90% (63% to 97%). All three vaccines remained effective at the time of circulation of the delta variant of SARS-CoV-2 between 1 July and 20 August 2021 (effectiveness between 89% and 95%).

Conclusions

These findings provide evidence indicating that two doses of ChAdOx1-S is as effective as two doses of mRNA vaccines in France against the alpha and delta variants of SARS-CoV-2. The effectiveness of ChAdOx1-S should be further examined with a longer follow-up and in the light of the circulation of new SARS-CoV-2 variants of concern.

Immunogenicity after 6 months of BNT162b2 vaccination in frail or disabled nursing home residents: The COVID-A Study

BACKGROUND

There is incomplete information regarding evolution of antibody titers against SARS-CoV-2 after a two-dose strategy vaccination with BNT162b2 in older adults in long-term care facilities (LTCFs) with frailty, disability, or cognitive impairment. We aimed to determine IgG antibody titer loss in older adults in LTCFs.

METHODS

This is a multicenter longitudinal cohort study including 127 residents (90 females and 37 males) with a mean age of 82.7 years (range 65-99) with different frailty and disability profiles in two LTCFs in Albacete, Spain. Residents received two doses of BNT162b2 as per label, and antibody levels were determined 1 and 6 months after the second dose. Age, sex, previous history of coronavirus disease 2019 (COVID-19), comorbidity (Charlson Index), performance in activities of daily living (Barthel Index), frailty (FRAIL instrument), and cognitive status were assessed.

RESULTS

The mean antibody titers 1 and 6 months after the second vaccine dose were 32,145 AU/ml (SD 41,206) and 6182 AU/ml (SD 13,316), respectively. Across all participants, the median antibody titer loss measured 77.6% (interquartile range [IQR] 23.8%). Notably, the decline of titers in individuals with pre-vaccination COVID-19 infection was significantly lower than in those without a history of SARS-CoV-2 infection (72.2% vs. 85.3%; p < 0.001). The median titer decrease per follow-up day was 0.47% (IQR 0.14%) and only pre-vaccination COVID-19 was associated with lower rate of antibody decline at 6 months (hazard ratio 0.17; 95% confidence interval 0.07-0.41; p < 0.001). Frailty, disability, older age, cognitive impairment, or comorbidity were not associated with the extent of antibody loss.

CONCLUSIONS

Older adults in LTCFs experience a rapid loss of antibodies over the first 6 months after the second dose of BNT162b2 vaccine. Only pre-vaccination COVID-19 is associated with a slower rate of antibody decrease. Our data support immunization with a third dose in this vulnerable, high-risk population.