A systematic review and meta-analysis of the effectiveness and safety of COVID-19 vaccination in older adults

The type of COVID-19 vaccination does not affect reproductive function and pregnancy outcomes in infertile couples

Introduction

Studies on the effect of vaccine type and two other vaccines other than inactivated vaccines approved in China on in vitro fertilization (IVF) pregnancy outcomes are rare. To complement and confirm the existing findings, this research aimed to investigate whether there are adverse effects of different vaccine types in females and males on reproductive function and clinical pregnancy.

Methods

This retrospective study enrolled 6,455 fresh embryo transfer cycles at the First Affiliated Hospital of Zhengzhou University between May 1, 2021, and October 31, 2022. The primary outcome is the clinical pregnancy rate (CPR). At the same time, the secondary results are the number of oocytes retrieved, two pronuclei (2PN) rate, blastocyst formation rate, high-quality blastocyst rate, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DNA fragment index (DFI) rate).

Results

In the comparison of ovarian stimulation indicators, no statistically significant differences (P > 0.05) were found in Gn days, endometrial thickness, 2PN rate, metaphase 2 (MII) rate, high-quality embryo rate, and blastocyst formation rate. No significant differences (P>0.05) were found in age, body mass index (BMI), education level, and semen parameters (volume, density, sperm count, forward motility rate, total motility rate, immobility rate, and DFI rate) in these four groups. The multivariate regression model showed that neither the types of vaccines nor the vaccination status of both infertile couples significantly affected clinical pregnancy.

Discussion

The type of vaccine does not appear to have an unfavorable effect on ovarian stimulation, embryo development, semen parameters, and clinical pregnancy.

Preparing for future pandemics: frailty associates with mortality in hospitalised older people during the entire COVID-19 pandemic, a Dutch multicentre cohort study

PURPOSE

Viral mutations and improved prevention or treatment options may have changed the association of frailty with mortality throughout the COVID-19 pandemic. We investigated how associations of frailty with in-hospital mortality changed throughout the pandemic in older people hospitalised for COVID-19.

METHODS

The COVID-OLD study included COVID-19 patients aged ≥ 70 years hospitalised during the first (early 2020), second (late 2020), third (late 2021) or fourth wave (early 2022). Based on the clinical frailty scale, patients were categorised as fit (1-3), pre-frail (4-5) or frail (6-9). Associations of frailty with in-hospital mortality were assessed with pairwise comparisons with fit as reference category and modelled using binary logistic regression adjusted for age and sex.

RESULTS

This study included 2362 patients (mean age 79.7 years, 60% men). In the first wave, in-hospital mortality was 46% in patients with frailty and 27% in fit patients. In-hospital mortality decreased in each subsequent wave to 25% in patients with frailty and 11% in fit patients in the fourth wave. After adjustments, an overall higher risk of in-hospital mortality was found in frail (OR 2.26, 95% CI: 1.66-3.07) and pre-frail (OR 1.73, 95% CI: 1.27-2.35) patients compared to fit patients, which did not change over time (p for interaction = 0.74).

CONCLUSIONS

Frailty remained associated with a higher risk of in-hospital mortality throughout the entire COVID-19 pandemic, although overall in-hospital mortality rates decreased. Frailty therefore remains a relevant risk factor in all stages of a pandemic and is important to consider in prevention and treatment guidelines for future pandemics.

Vaccines for the Elderly and Vaccination Programs in Europe and the United States

The share of the elderly population is growing worldwide as life expectancy increases. Immunosenescence and comorbidities increase infectious diseases' morbidity and mortality in older adults. Here, we aimed to summarize the latest findings on vaccines for the elderly against herpes zoster, influenza, respiratory syncytial virus (RSV), COVID-19, and pneumococcal disease and to examine vaccine recommendation differences for this age group in Europe and the United States. PubMed was searched using the keywords "elders" and "vaccine" alongside the disease/pathogen in question and paraphrased or synonymous terms. Vaccine recommendations were also sought in the European and US Centers for Disease Control and Prevention databases. Improved vaccines, tailored for the elderly, mainly by using novel adjuvants or by increasing antigen concentration, are now available. Significant differences exist between immunization policies, especially between European countries, in terms of the recipient's age, number of doses, vaccination schedule, and implementation (mandatory or recommended). Understanding the factors that influence the immune response to vaccination in the elderly may help to design vaccines that offer long-term protection for this vulnerable age group. A consensus-based strategy in Europe could help to fill the gaps in immunization policy in the elderly, particularly regarding vaccination against RSV and pneumococcus.

Current Progress, Challenges and Prospects in the Development of COVID-19 Vaccines

The COVID-19 pandemic has resulted in over 772 million confirmed cases, including nearly 7 million deaths, according to the World Health Organization (WHO). Leveraging rapid development, accelerated vaccine approval processes, and large-scale production of various COVID-19 vaccines using different technical platforms, the WHO declared an end to the global health emergency of COVID-19 on May 5, 2023. Current COVID-19 vaccines encompass inactivated, live attenuated, viral vector, protein subunit, nucleic acid (DNA and RNA), and virus-like particle (VLP) vaccines. However, the efficacy of these vaccines is diminishing due to the constant mutation of SARS-CoV-2 and the heightened immune evasion abilities of emerging variants. This review examines the impact of the COVID-19 pandemic, the biological characteristics of the virus, and its diverse variants. Moreover, the review underscores the effectiveness, advantages, and disadvantages of authorized COVID-19 vaccines. Additionally, it analyzes the challenges, strategies, and future prospects of developing a safe, broad-spectrum vaccine that confers sufficient and sustainable immune protection against new variants of SARS-CoV-2. These discussions not only offer insight for the development of next-generation COVID-19 vaccines but also summarize experiences for combating future emerging viruses.

Changes in the innate immune response to SARS-CoV-2 with advancing age in humans

BACKGROUND

Advancing age is a major risk factor for respiratory viral infections. The infections are often prolonged and difficult to resolve resulting hospitalizations and mortality. The recent COVID-19 pandemic has highlighted this as elderly subjects have emerged as vulnerable populations that display increased susceptibility and severity to SARS-CoV-2. There is an urgent need to identify the probable mechanisms underlying this to protect against future outbreaks of such nature. Innate immunity is the first line of defense against viruses and its decline impacts downstream immune responses. This is because dendritic cells (DCs) and macrophages are key cellular elements of the innate immune system that can sense and respond to viruses by producing inflammatory mediators and priming CD4 and CD8 T-cell responses.

RESULTS

We investigated the changes in innate immune responses to SARS-CoV-2 as a function of age. Our results using human PBMCs from aged, middle-aged, and young subjects indicate that the activation of DCs and monocytes in response to SARS-CoV-2 is compromised with age. The impairment is most apparent in pDCs where both aged and middle-aged display reduced responses. The secretion of IL-29 that confers protection against respiratory viruses is also decreased in both aged and middle-aged subjects. In contrast, inflammatory mediators associated with severe COVID-19 including CXCL-8, TREM-1 are increased with age. This is also apparent in the gene expression data where pathways related host defense display an age dependent decrease with a concomitant increase in inflammatory pathways. Not only are the inflammatory pathways and mediators increased after stimulation with SARS-CoV-2 but also at homeostasis. In keeping with reduced DC activation, the induction of cytotoxic CD8 T cells is also impaired in aged subjects. However, the CD8 T cells from aged subjects display increased baseline activation in accordance with the enhanced baseline inflammation.

CONCLUSIONS

Our results demonstrate a decline in protective anti-viral immune responses and increase in damaging inflammatory responses with age indicating that dysregulated innate immune responses play a significant role in the increased susceptibility of aged subjects to COVID-19. Furthermore, the dysregulation in immune responses develops early on as middle-aged demonstrate several of these changes.

Sarcopenic patients "get even": The impact of COVID-19 vaccination on mortality

BACKGROUND

Coronavirus Disease-2019 (COVID-19), driven by the SARS-CoV-2 virus, has disproportionately affected the elderly, with comorbidities like sarcopenia worsening prognosis. Considering the significant impact of RNA vaccines on survival rates in this population, our objective is to investigate the impact of vaccination on the survival of hospitalized elderly patients with COVID-19, considering the presence or absence of sarcopenia.

METHODS

Prospective study conducted on 159 patients aged>65 years from September 2021 to March 2022. Data about clinical and body composition, and mortality at 12-months after discharge were recorded. Sarcopenia was diagnosed according to the 2019 European Consensus criteria.

RESULTS

At the twelfth month post-discharge, vaccinated sarcopenic individuals exhibited a mortality risk similar to vaccinated non-sarcopenic individuals, and lower than unvaccinated non-sarcopenic patients. Cox regression analysis, adjusted for age, gender, comorbidity, functional and vaccinal status, showed that the presence of sarcopenia did not significantly impact the risk of death within 12-months post-discharge.

DISCUSSION

Vaccination emerges as a protective measure for sarcopenic patients, countering the potential adverse effects of sarcopenia on COVID-19 outcomes, underscoring the importance of immunization in the frail elderly with a call for meticulous monitoring of its benefits.

CONCLUSIONS

Our study represents the first attempt to analyze the vaccine's effect on survival in sarcopenic hospitalized older adults with COVID-19. The administration of vaccination to sarcopenic patients proves pivotal, as its omission could lead to notably unfavorable outcomes within this specific population.

An analysis of COVID-19 vaccination campaign in Ukraine

BACKGROUND

The Coronavirus disease (COVID-19) pandemic is still an important problem of concern in Ukraine. The rapid deployment of the vaccination program is a key event for the formation of herd immunity and helps to prevent negative outcomes, overloading the public health system.

METHODS

The object of the retrospective-archival study was a depersonalized database of open panels on the management of the COVID-19 situation from the Ministry of Health of Ukraine.

RESULTS

The total number of COVID-19 cases in Ukraine as of 25 December 2022 amounted to 5 314 388 individuals (12.83% of the population), and COVID-19-related deaths reached 110 029 individuals (0.26% of the population). The overall number of COVID-19 vaccinated persons in Ukraine as of 16 January 2022, with one dose was 36 198 per 100 000 persons (36% of the population), and with two doses, it was 34 703 per 100 000 persons (35% of the population). It was shown a decrease in the number of COVID-19 vaccinated persons among men and persons over the age of 70. In the dynamics of COVID-19 vaccination with one and two doses, an increase in the number of persons vaccinated with Pfizer/BioNTech and CoronaVac was noted.

CONCLUSIONS

Despite the significant increase in the morbidity and mortality rates of COVID-19, the coverage of vaccination among the population remained insufficient in Ukraine. The effective COVID-19 vaccination strategy should include appropriate management and ensuring the public health system capacity, implementation of information technologies to address logistics issues, and clear communication strategies to maintain public trust.

Vaccine conspiracy association with higher COVID-19 vaccination side effects and negative attitude towards booster COVID-19, influenza and monkeypox vaccines: A pilot study in Saudi Universities

Conspiracies regarding vaccines are widely prevalent, with negative consequences on health-seeking behaviors. The current study aimed to investigate the possible association between the embrace of vaccine conspiracies and the attitude to booster COVID-19, seasonal influenza, and monkeypox (mpox) vaccinations as well as the perceived side effects following COVID-19 vaccination. The target population involved academic staff and university students in health colleges in the Kingdom of Saudi Arabia. A self-administered questionnaire was distributed in January 2023 to collect data on participants' demographics, self-reported side effects following each dose, willingness to get booster COVID-19, seasonal influenza, and mpox vaccinations, as well as an evaluation of vaccine conspiracies and attitude to mandatory vaccination. Among the 273 participants, the willingness to receive yearly booster COVID-19 vaccination was observed among 26.0% of the participants, while it was 46.9% and 34.1% for seasonal influenza and mpox vaccinations, respectively. Multinomial logistic regression analyses demonstrated a significant correlation between endorsing vaccine conspiracies and higher frequency of self-reported side effects following uptake of the second and third doses of COVID-19 vaccines. Vaccine conspiracies were also correlated with attitude toward booster COVID-19, influenza, mpox, and mandatory vaccination. The findings of this pilot study highlighted the potential adverse impact of the preexisting notions and negative attitudes toward vaccines, which could have contributed to heightened perceived side effects following COVID-19 vaccination. The study also highlighted the ongoing divisions concerning mandatory vaccination policies, emphasizing the need for cautious implementation of this strategy as a last resort for public health benefit.

Unraveling the association between vaccine attitude, vaccine conspiracies and self-reported side effects following COVID-19 vaccination among nurses and physicians in Jordan

Background

The negative impact of vaccine conspiracies is linked with negative health behavior. The aim of the current study was to examine the association between attitudes toward booster COVID-19, influenza, and monkeypox (mpox) vaccinations with post-COVID-19 vaccine side effects, vaccine conspiracies, and attitude towards mandatory vaccination among nurses and physicians in Jordan.

Methods

A structured closed-ended questionnaire was used to collect data on demographics, COVID-19 history, COVID-19 vaccine type and doses received, self-reported side effects post-COVID-19 vaccination, acceptance of booster COVID-19, seasonal influenza, and mpox vaccinations, attitudes towards mandatory vaccination, and beliefs in vaccine conspiracies.

Results

The study sample comprised a total of 341 participants. Acceptance of yearly booster COVID-19 vaccination was expressed by 46.6% of the sample, while 73.3% accepted seasonal influenza vaccination, and only 37.0% accepted mpox vaccination. A higher frequency of self-reported side effects following the first COVID-19 vaccine dose was associated with embrace of vaccine conspiracies and vaccine type. For the second vaccine dose, a higher frequency of self-reported side effects was associated with the embrace of vaccine conspiracies, older age, and affiliation to private sector. In multinomial logistic regression analyses, the lower embrace of vaccine conspiracies was associated with lower odds of reporting side effects post-COVID-19 vaccination. The lower embrace of vaccine conspiracies and favorable attitude towards mandatory vaccination were associated with the willingness to get COVID-19, influenza, and mpox vaccinations.

Conclusion

The study findings highlighted the negative impact of embracing vaccine conspiracies on health-seeking behavior among nurses and physicians. The findings indicated that the willingness to get vaccinated was associated with lower endorsement of vaccine conspiracies. Additionally, the lower embrace of vaccine conspiracies was associated with a lower frequency of self-reported side effects following COVID-19 vaccination. These results emphasize the importance of addressing vaccine misinformation and promoting accurate information to ensure optimal vaccine uptake and public health outcomes.

Point Prevalence Survey of Antimicrobial Use and Resistance during the COVID-19 Era among Hospitals in Saudi Arabia and the Implications

The inappropriate prescribing of antimicrobials increases antimicrobial resistance (AMR), which poses an appreciable threat to public health, increasing morbidity and mortality. Inappropriate antimicrobial prescribing includes their prescribing in patients hospitalized with COVID-19, despite limited evidence of bacterial infections or coinfections. Knowledge of current antimicrobial utilization in Saudi Arabia is currently limited. Consequently, the objective of this study was to document current antimicrobial prescribing patterns among Saudi hospitals during the COVID-19 pandemic. This study included patients with or without COVID-19 who were admitted to five hospitals in Makkah, Saudi Arabia. Data were gathered using the Global PPS methodology and analyzed using descriptive statistics. Out of 897 hospitalized patients, 518 were treated with antibiotics (57.7%), with an average of 1.9 antibiotics per patient. There were 174 culture reports collected, representing 36.5% of all cases. The most common indication for antibiotics use was community-acquired infections, accounting for 61.4% of all cases. 'Watch' antibiotics were the most commonly prescribed antibiotics, with the cephalosporins and carbapenems representing 38.7% of all antibiotics prescribed, followed by the penicillins (23.2%). Notably, Piperacillin/Tazobactam and Azithromycin were prescribed at relatively higher rates for COVID-19 patients. These findings highlight the need for continuous efforts to optimize the rational use of antibiotics through instigating appropriate antimicrobial stewardship programs in hospitals and, as a result, reduce AMR in the country.

Evolution of Cardiovascular Risk Factors in Post-COVID Patients

(1) Background: SARS-CoV-2 infection has been a subject of extensive discussion in the medical field, particularly in relation to the risk factors and effective treatment strategies for reducing the negative health outcomes associated with the virus. However, researchers indicate that individuals in the recovery phase after COVID-19 experience a range of symptoms that significantly impact their overall well-being and quality of life. At present, there is insufficient evidence to substantiate the claim that patients in the post-acute phase of COVID-19 are at an elevated risk of developing new-onset hypertension or even metabolic syndrome. The current study aimed to assess the risk of cardiovascular diseases after COVID-19 and the optimal treatment of these conditions. (2) Methods: This research was conducted at the Cardiovascular Rehabilitation Clinic of the Iasi Clinical Rehabilitation Hospital (Romania) between the 1st of September and 31st of December 2022. From a total of 551 patients hospitalized in that period, 70 patients with multiple comorbidities were selected. This study included patients over 18 years old who were diagnosed with COVID-19 within the past 30 days. (3) Results: The included patients were mostly women (62.9%) from the urban area (61.4%). Comparing the post-COVID-19 period to the pre-COVID-19 one, it was observed that the risk of hypertension increased from 69.57% to 90% among the subjects (p = 0.005). Risk factors for the new onset of hypertension were identified as age, female gender, and an elevated body mass index. Moreover, the number of patients with dyslipidemia doubled, and a higher body mass index was noted. (4) Conclusions: Our findings suggest that patients affected by COVID-19 are at an increased risk of developing hypertension and related disorders.

Heterologous DNA-prime/protein-boost immunization with a monomeric SARS-CoV-2 spike antigen redundantizes the trimeric receptor-binding domain structure to induce neutralizing antibodies in old mice

A multitude of alterations in the old immune system impair its functional integrity. Closely related, older individuals show, for example, a reduced responsiveness to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines. However, systematic strategies to specifically improve the efficacy of vaccines in the old are missing or limited to simple approaches like increasing the antigen concentration or injection frequencies. We here asked whether the intrinsic, trimeric structure of the SARS-CoV-2 spike (S) antigen and/or a DNA- or protein-based antigen delivery platform affects priming of functional antibody responses particularly in old mice. The used S-antigens were primarily defined by the presence/absence of the membrane-anchoring TM domain and the closely interlinked formation/non-formation of a trimeric structure of the receptor binding domain (S-RBD). Among others, we generated vectors expressing prefusion-stabilized, cell-associated (TM+) trimeric "S2-P" or secreted (TM-) monomeric "S6-PΔTM" antigens. These proteins were produced from vector-transfected HEK-293T cells under mild conditions by Strep-tag purification, revealing that cell-associated but not secreted S proteins tightly bound Hsp73 and Grp78 chaperones. We showed that both, TM-deficient S6-PΔTM and full-length S2-P antigens elicited very similar S-RBD-specific antibody titers and pseudovirus neutralization activities in young (2-3 months) mice through homologous DNA-prime/DNA-boost or protein-prime/protein-boost vaccination. The trimeric S2-P antigen induced high S-RBD-specific antibody responses in old (23-24 months) mice through DNA-prime/DNA-boost vaccination. Unexpectedly, the monomeric S6-PΔTM antigen induced very low S-RBD-specific antibody titers in old mice through homologous DNA-prime/DNA-boost or protein-prime/protein-boost vaccination. However, old mice efficiently elicited an S-RBD-specific antibody response after heterologous DNA-prime/protein-boost immunization with the S6-PΔTM antigen, and antibody titers even reached similar levels and neutralizing activities as in young mice and also cross-reacted with different S-variants of concern. The old immune system thus distinguished between trimeric and monomeric S protein conformations: it remained antigen responsive to the trimeric S2-P antigen, and a simple change in the vaccine delivery regimen was sufficient to unleash its reactivity to the monomeric S6-PΔTM antigen. This clearly shows that both the antigen structure and the delivery platform are crucial to efficiently prime humoral immune responses in old mice and might be relevant for designing "age-adapted" vaccine strategies.

COVID-19 Vaccine Acceptance and Hesitancy among Healthcare Workers in Lusaka, Zambia; Findings and Implications for the Future

The uptake of COVID-19 vaccines is critical to address the severe consequences of the disease. Previous studies have suggested that many healthcare workers (HCWs) are hesitant to receive the COVID-19 vaccine, further enhancing hesitancy rates within countries. COVID-19 vaccine acceptance and hesitancy levels are currently unknown among HCWs in Zambia, which is a concern given the burden of infectious diseases in the country. Consequently, this study assessed COVID-19 vaccine acceptance and hesitancy among HCWs in Lusaka, Zambia. A cross-sectional study was conducted among 240 HCWs between August and September 2022, using a semi-structured questionnaire. Multivariable analysis was used to determine the key factors associated with vaccine hesitancy among HCWs. Of the 240 HCWs who participated, 54.2% were females. A total of 72.1% of the HCWs would accept being vaccinated, while 27.9% were hesitant. Moreover, 93.3% of HCWs had positive attitudes towards COVID-19 vaccines, with medical doctors having the highest mean attitude score (82%). Encouragingly, HCWs with positive attitudes towards COVID-19 vaccines had reduced odds of being hesitant (AOR = 0.02, 95% CI: 0.01-0.11, p < 0.001). Overall, acceptance of the COVID-19 vaccine among HCWs in Lusaka, Zambia, was high, especially by those with positive attitudes. However, the current hesitancy among some HCWs is a concern. Consequently, there is a need to address this and encourage HCWs to fully promote vaccination programs going forward.