Vaccine Brand Research Articles

Vaccine Quality Challenges in Secretly Traded H5 and H9 Avian Influenza Vaccines in Nigeria

Avian Influenza Virus (AIV) especially the highly pathogenic subtype H5Nx causes Avian Influenza (AI) disease and it is a major threat to the poultry industry and public health worldwide. Vaccination is one of the control measures in many countries, though restricted in Nigeria. As such, some poultry farmers secretly employ imported H5 and H9 AI vaccines to vaccinate their chickens. This study investigated the antigenic quality of these imported vaccines. Four imported vaccine brands were tested using Hemagglutination (HA) test and Reverse Transcriptase Polymerase Chain Reaction (RTPCR). All four vaccine samples tested negative in the HA test, indicating a lack of detectable HA antigen titer. Similarly, RT-PCR failed to amplify the targeted region of the viral matrix gene in any of the vaccine samples against reference control. These negative results are of great concern and suggest that the imported H5 and H9 vaccines lack essential antigens that could stimulate antibodies. Thus, potentially rendering them ineffective against circulating AI subtypes. The failure in antigenic quality could be due to myriads of factors including improper storage, transport (often due to illegal import), or limitations in the original vaccine production process. Regardless of the specific cause, these findings highlight the potential risks associated with the use of unregulated vaccines. Poultry farmers who use these imported vaccines may be incurring unnecessary costs while receiving a false sense of security for their flocks. In conclusion, due to the apparent lack of efficacious antigens, we suggest a quality monitoring of imported H5 and H9 vaccines in Nigeria for compliance with local regulations on vaccine use, biosecurity measures and investigation into the root causes of the vaccine failure observed in this study.

The Great Vaccine Divide: A Comparative Analysis of Distrust in Covid-19 Vaccines in Turkey

The aim of this study is to identify key predictors of public distrust in different Covid-19 vaccines available in Turkey. We use multiple linear regression with robust standard errors to analyze the data from the 2022 Turkey Covid-19 Values Survey of 1,500 face-to-face interviews across Turkey. Our results show that Pfizer/BioNTech has the lowest level of distrust, followed by Sinovac and Turkovac. Trust in political institutions and health institutions significantly reduce distrust for all vaccine brands. However, conspiracy beliefs and political conservatism are linked to higher distrust in Sinovac and BioNTech, while increased religiosity correlates with more distrust in BioNTech but less in Turkovac. Our comparative brand analysis adds an essential perspective to the existing literature while highlighting the necessity of maintaining public trust in institutions. It also demonstrates the importance of brand-specific strategies in promoting vaccines and addressing challenges faced by populations for more successful public health initiatives.

Safety of COVID-19 Vaccines among People with History of Allergy: A European Active Surveillance Study.

Background: Conventional vaccines rarely cause severe allergic reactions. However, the rapid development and approval of COVID-19 vaccines left limited initial data on their adverse reactions, particularly in individuals with a history of allergy. The aim of this study was to assess and compare the safety profile of different doses and brands of COVID-19 vaccines in subjects with a history of allergy vs. those without a history of allergy. Methods: From February 2021 to February 2023, a web-based prospective study gathered vaccinee-reported outcomes using electronic questionnaires across eleven European countries. Baseline and up to six follow-up questionnaires captured data on vaccinee demographics, as well as both solicited and unsolicited adverse reactions. Results: Overall, 3476 vaccinees with a history of allergy were matched with 13,872 vaccinees from the general population at the first vaccination cycle and were included in the analysis. A total of 825 vaccinees with a history of allergy who had received a booster dose, matched to 3297 vaccinees from the general population, were included in the analysis. Higher rates of ADRs occurred after the first vaccination cycle compared to after the booster dose (64-91% vs. 56-79%). However, most reported ADRs were solicited and not serious, and no case of anaphylaxis was reported. Women and vaccinees with a history of allergy reported ADRs more frequently than men and the matched controls, respectively. Compared to other COVID-19 vaccines, a higher proportion of vaccinees experiencing at least one ADR following their first vaccination cycle was observed with Comirnaty and Vaxzevria. Statistically significant differences were observed among the study cohorts for median TTO after the second dose, and for median TTR following the first vaccination cycle and booster dose (p < 0.001). Conclusions: Typically, any drug or vaccine use carries a risk of severe allergic reactions, yet the benefits of vaccination generally outweigh these potential risks, as shown with the COVID-19 vaccines.

The descriptive epidemiology of adverse events following two doses of mRNA COVID-19 vaccination in Curaçao, the Caribbean

Background BNT162b2 and mRNA-1273 COVID-19 vaccines have been used for mass vaccinations in Curaçao, the Caribbean but information on adverse events (AEs)in this population is unavailable. This study describes the characteristics of vaccinees that incurred AEs, explores the associations between AEs by vaccine and doses, and estimates the rate of AEs. Methods Vaccination and AEs data for all persons of age 5 years (range 5–105 years) and older who received two doses of COVID-19 vaccine at 71 centres in Curaçao between February 24, 2021, and April 5, 2023, were included in this retrospective observational study. Results The vaccines differed significantly in the frequency distribution of vaccinees by age, age groups, sex, AEs, and prior COVID-19 infection. Occurrence of AEs was strongly associated with mRNA vaccine brand, sex, number of doses, but not with age, age group, and prior COVID-19 infection. Of 209,720 doses, 84 persons (0.04%) incurred AEs following two doses of mRNA vaccines (overall rate of 40.1 per 100,000 persons (95% CI 32.4–49.6). AEs were also significantly higher in females compared to males.AE rates associated with BNT162b2, and mRNA-1273 vaccines were low, but BNT162b2 vaccinees incurred substantially significantly higher AE rates (58.3 per 100,000 persons, 95% CI 45.4–74.9) than mRNA-1273 vaccinees (21.9 per 100,000 persons, 95% CI 14.6–32.8). mRNA-1273 vaccine was associated with a significantly lower risk of AEs. Conclusions AE reporting varied by age, sex, and vaccine used as well as the number of doses. Future studies with follow-up and longer-term reporting of AEs should be conducted.

Acceptance of a third COVID-19 vaccine dose, vaccine interchangeability, and clinical trial enrolment among parents of children 12-17 years in Lima, Perú.

To characterize factors associated with parental willingness for their children participation in a COVID-19 vaccine trial, use of different COVID-19 vaccines and acceptance of a third vaccine dose. Parents of children aged 12-17 years in Lima, Perú were asked to complete an online questionnaire via social networks, from November 9, 2021, to April 23, 2022. We calculated crude and adjusted prevalence ratios with 95% confidence intervals to compare factors with the mentioned outcomes. From 523 parents responding, 374 completed the survey. 90.4% would give their children a third vaccine dose, 36.6% would allow their children participation in a COVID-19 vaccine clinical trial, and 33.2% would accept different vaccine brands between doses. Parental belief that COVID-19 vaccine studies met quality standards was associated with acceptance of a third booster dose (adjusted PR 3.25; 95% CI1.57-6.74; p = 0.002), enrolment in a COVID-19 clinical trial (adjusted PR 4.49; 95% CI1.25-16.06; p = 0.02), and acceptance of different COVID-19 vaccine brands between doses (adjusted PR 10.02; 95% CI1.40-71.95; p = 0.02). Most parents would accept a third vaccine booster dose, approximately a third would participate in COVID-19 vaccine trials. Believing COVID-19 vaccines studies fulfilled quality standards was associated with the study outcomes. It is necessary to inform about the rigorous processes for the development of COVID-19 vaccines to generate confidence in parents to accept these vaccine-related outcomes.

Factors affecting the outcome of primary rabies vaccination in young cats

Limited data exist on the factors affecting feline rabies vaccination outcomes during primary immunization. This study aimed to assess if specific factors (signalment, vaccination count, vaccine brand, and time since last vaccination) correlated with meeting global antibody titer standards and absolute titers in young cats given monovalent inactivated rabies vaccines. Analyzing a dataset from cats tested before their first annual booster using the FAVN test, logistic and linear regression models were applied. Among 379 cats, 94.2 % achieved titers meeting or exceeding the standard threshold (≥0.5 IU/ml). Time since last vaccination proved to be the primary predictor of vaccination success. Cats receiving two vaccinations tended toward higher titers. Age, sex, breed, and vaccine type showed no impact on outcomes. The present study indicates that vaccination failure in young cats is uncommon, and that the time interval from the latest vaccination is the single most important predictor of successful rabies vaccination.

Cohort study of cardiovascular safety of different COVID-19 vaccination doses among 46 million adults in England

The first dose of COVID-19 vaccines led to an overall reduction in cardiovascular events, and in rare cases, cardiovascular complications. There is less information about the effect of second and booster doses on cardiovascular diseases. Using longitudinal health records from 45.7 million adults in England between December 2020 and January 2022, our study compared the incidence of thrombotic and cardiovascular complications up to 26 weeks after first, second and booster doses of brands and combinations of COVID-19 vaccines used during the UK vaccination program with the incidence before or without the corresponding vaccination. The incidence of common arterial thrombotic events (mainly acute myocardial infarction and ischaemic stroke) was generally lower after each vaccine dose, brand and combination. Similarly, the incidence of common venous thrombotic events, (mainly pulmonary embolism and lower limb deep venous thrombosis) was lower after vaccination. There was a higher incidence of previously reported rare harms after vaccination: vaccine-induced thrombotic thrombocytopenia after first ChAdOx1 vaccination, and myocarditis and pericarditis after first, second and transiently after booster mRNA vaccination (BNT-162b2 and mRNA-1273). These findings support the wide uptake of future COVID-19 vaccination programs.

Statistical considerations for the platform trial in COVID-19 vaccine priming and boosting

The Platform trial In COVID-19 priming and BOOsting (PICOBOO) is a multi-site, adaptive platform trial designed to generate evidence of the immunogenicity, reactogenicity, and cross-protection of different booster vaccination strategies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants, specific for the Australian context. The PICOBOO trial randomises participants to receive one of three COVID-19 booster vaccine brands (Pfizer, Moderna, Novavax) available for use in Australia, where the vaccine brand subtypes vary over time according to the national vaccine roll out strategy, and employs a Bayesian hierarchical modelling approach to efficiently borrow information across consecutive booster doses, age groups and vaccine brand subtypes. Here, we briefly describe the PICOBOO trial structure and report the statistical considerations for the estimands, statistical models and decision making for trial adaptations. This paper should be read in conjunction with the PICOBOO Core Protocol and PICOBOO Sub-Study Protocol 1: Booster Vaccination. PICOBOO was registered on 10 February 2022 with the Australian and New Zealand Clinical Trials Registry ACTRN12622000238774.

GP consultations for menstrual disorders after COVID-19 vaccination – A self-controlled cohort study based on routine healthcare data from the Netherlands

IntroductionSeveral studies described that COVID-19 vaccinations can cause menstrual disorders. Our study aimed to describe whether this also resulted in more general practitioner (GP) consultations for menstrual disorders after COVID-19 vaccination, based on a large cohort study. MethodsA retrospective self-controlled cohort study was performed including vaccinated women in 2021 aged 12–49 years from two large, representative GP databases in the Netherlands. Incidence rates and incidence rate ratio’s (IRR) were calculated using Poisson regression, adjusting for SARS-CoV-2 infection as time-varying confounder. The exposed period was set at maximum six months after each COVID-19 vaccination and the non-exposed period was defined as all-time outside the exposed period. ResultsThe cohort included 631,802 women, of which 18,986 (3 %) consulted the GP for a menstrual disorder during 2021. Increased GP consultations were observed among 12–14 year olds for amenorrhea/hypomenorrhea/oligomenorrhea (IRR: 1.85, 95 % CI: 1.30–2.65) and irregular/frequent menstruation (IRR: 1.33, 95 % CI: 1.06–1.69) after COVID-19 vaccination in general, and after Pfizer/BioNTech vaccination (IRR: 1.87, 95 % CI: 1.31–2.67 for amenorrhea/hypomenorrhea/oligomenorrhea and IRR: 1.35, 95 % CI: 1.06–1.70 for irregular/frequent menstruation). Persons from this age group were in general also vaccinated with Pfizer/BioNTech. No increase in the frequency of GP consultations were observed for older age groups, other vaccine brands, and potential risk groups. ConclusionFor the majority of women, no increased GP consultations for menstrual disorders was found. Solely for the youngest age group (12–14 year olds) increased GP consultations for specific types of menstrual disorders was found after Pfizer/BioNTech vaccination.

Exploring SARS-CoV-2 infection and vaccine-induced immunity in chronic myeloid leukemia patients: insights from real-world data in Brazil and the United States

This study investigates COVID-19 outcomes and immune response in chronic myeloid leukemia (CML) patients post-SARS-CoV-2 vaccination, comparing effectiveness of various vaccine options. Data from 118 CML patients (85 in Brazil, 33 in the US) showed similar infection rates prior (14% Brazil, 9.1% US) and post-vaccination (24.7% vs. 27.3%, respectively). In Brazil, AstraZeneca and CoronaVac were the most commonly used vaccine brands, while in the US, Moderna and Pfizer-BioNTech vaccines dominated. Despite lower seroconversion in the Brazilian cohort, all five vaccine brands analyzed prevented severe COVID-19. Patients who received mRNA and recombinant viral vector vaccines (HR: 2.20; 95%CI 1.07–4.51; p < .031) and those that had achieved at least major molecular response (HR: 1.51; 95% CI 1.01–3.31; p < .0001) showed higher seroconversion rates. Our findings suggest that CML patients can generate antibody responses regardless of the vaccine brand, thereby mitigating severe COVID-19. This effect is more pronounced in patients with well-controlled disease.

Predictors of COVID-19 vaccine acceptability among refugees and other migrant populations: A systematic scoping review.

This study aimed to map the existing literature to identify predictors of COVID-19 vaccine acceptability among refugees, immigrants, and other migrant populations. A systematic search of Medline, Embase, Scopus, APA PsycInfo and Cumulative Index of Nursing and Allied Health Literature (CINAHL) was conducted up to 31 January 2023 to identify the relevant English peer-reviewed observational studies. Two independent reviewers screened abstracts, selected studies, and extracted data. We identified 34 cross-sectional studies, primarily conducted in high income countries (76%). Lower vaccine acceptance was associated with mistrust in the host countries' government and healthcare system, concerns about the safety and effectiveness of COVID-19 vaccines, limited knowledge of COVID-19 infection and vaccines, lower COVID-19 risk perception, and lower integration level in the host country. Female gender, younger age, lower education level, and being single were associated with lower vaccine acceptance in most studies. Additionally, sources of information about COVID-19 and vaccines and previous history of COVID-19 infection, also influence vaccine acceptance. Vaccine acceptability towards COVID-19 booster doses and various vaccine brands were not adequately studied. Vaccine hesitancy and a lack of trust in COVID-19 vaccines have become significant public health concerns within migrant populations. These findings may help in providing information for current and future vaccine outreach strategies among migrant populations.

Applying two approaches to detect unmeasured confounding due to time-varying variables in a self-controlled risk interval design evaluating COVID-19 vaccine safety signals, using myocarditis as a case example.

We test the robustness of the self-controlled risk interval (SCRI) design in a setting where time between doses may introduce time-varying confounding, using both negative control outcomes (NCOs) and quantitative bias analysis (QBA). All vaccinated cases identified from 5 European databases between 1 September 2020 and end of data availability were included. Exposures were doses 1-3 of the Pfizer, Moderna, AstraZeneca, and Janssen COVID-19 vaccines; outcomes were myocarditis and otitis externa (NCO). The SCRI used a 60-day control window and dose-specific 28-day risk windows, stratified by vaccine brand and adjusted for calendar time. The QBA included two scenarios: (i) baseline probability of the confounder was higher in the control window and (ii) vice versa. The NCO was not associated with any of the COVID-19 vaccine types or doses except Moderna dose 1 (IRR = 1.09, 95%CI 1.01-1.09). The QBA suggested even the strongest literature-reported confounder (COVID-19; RRmyocarditis = 18.3) could only explain away part of the observed effect from IRR = 3 to IRR = 1.40. The SCRI seems robust to unmeasured confounding in the COVID-19 setting, although a strong unmeasured confounder could bias the observed effect upward. Replication of our findings for other safety signals would strengthen this conclusion.

What is the Safety of COVID-19 Vaccines in Immunocompromised Patients? Results from the European "Covid Vaccine Monitor" Active Surveillance Study.

The safety profile of COVID-19 vaccines in immunocompromised patients has not been comprehensively evaluated. To measure the frequency of patient-reported adverse drug reactions (ADRs) related to the first/second/booster dose of COVID-19 vaccine in immunocompromised subject versus matched cohort. As a secondary objective, the time course, evaluated as time to onset (TTO) and time to recovery (TTR), of COVID-19 vaccine-related ADRs was explored. A prospective cohort study, based on electronic questionnaires filled by vaccinees from 11 European countries in the period February 2021 to February 2023 was conducted. All immunocompromised vaccinees who provided informed consent and registered to the project's web-app within 48 h after first/booster vaccine dose administration of any EMA-authorised COVID-19 vaccine were recruited. Participants filled baseline and up to six follow-up questionnaires (FU-Qs) over 6 months from vaccination, collecting information on suspected COVID-19 vaccine-related ADRs. As a control group, non-immunocompromised vaccinees from the same source population were 1:4 matched by sex, age, vaccine dose, and brand. A descriptive analysis of demographic/clinical characteristics of vaccinees was conducted. Heatmaps of the frequency of solicited ADRs, stratified by gender and vaccine brand, were generated. Median TTO/TTR of reported ADRs were visualised using violin/box-plots. A total of 773 immunocompromised vaccines were included in the analyses. Most participants were females (F/M ratio: 2.1 and 1.6) with a median age of 56 (43-74) and 51 (41-60) years, at the first vaccination cycle and booster dose, respectively. Injection-site pain and fatigue were the most frequently reported ADRs in immunocompromised vaccinees with higher frequency than matched control, especially after the first dose (41.2% vs 37.8% and 38.2% vs 32.9%, respectively). For both cohorts, all solicited ADRs were more frequently reported in females than males, and in those who had received a first dose of the Vaxzevria vaccine. Dizziness was the most frequently reported unsolicited ADR after the first dose in both groups (immunocompromised subjects: 2.5% and matched controls: 2.1%). At the booster dose, lymphadenopathy (3.9%) and lymphadenitis (1.8%) were the most reported unsolicited ADRs for immunocompromised subjects and matched controls, respectively. A very low number of subjects reported adverse event of special interest (AESI) (2 immunocompromised, 3 matched controls) and serious ADRs (5 immunocompromised, 5 matched controls). A statistically significant difference among study cohorts was observed for median TTO after the booster dose, and for median TTR after the first vaccination cycle and booster dose (p < 0.001). The overall safety profile of COVID-19 vaccines in immunocompromised people was favourable, with minor differences as compared to non-immunocompromised vaccinees. Participants mostly experienced mild ADRs, mainly reported after the first dose of Vaxzevria and Jcovden vaccines. Serious ADRs and AESI were rare.

Real-World Assessment of Recommended COVID-19 Vaccination Waiting Period after Chemotherapy.

There is a knowledge gap concerning the proper timing for COVID-19 vaccination in cancer patients undergoing chemotherapy. We aimed to evaluate the suitability of the guidelines that recommend waiting at least three months after undergoing chemotherapy before receiving a COVID-19 vaccine. This retrospective cohort study used aggregated data from the TriNetX US Collaboratory network. Participants were grouped into two groups based on the interval between chemotherapy and vaccination. The primary outcome assessed was infection risks, including COVID-19; skin, intra-abdominal, and urinary tract infections; pneumonia; and sepsis. Secondary measures included healthcare utilization and all causes of mortality. Kaplan-Meier analysis and the Cox proportional hazard model were used to calculate the cumulative incidence and hazard ratio (HR) and 95% confidence intervals for the outcomes. The proportional hazard assumption was tested with the generalized Schoenfeld approach. Four subgroup analyses (cancer type, vaccine brand, sex, age) were conducted. Sensitivity analyses were performed to account for competing risks and explore three distinct time intervals. Patients receiving a vaccine within three months after chemotherapy had a higher risk of COVID-19 infection (HR: 1.428, 95% CI: 1.035-1.970), urinary tract infection (HR: 1.477, 95% CI: 1.083-2.014), and sepsis (HR: 1.854, 95% CI: 1.091-3.152) compared to those who adhered to the recommendations. Hospital inpatient service utilization risk was also significantly elevated for the within three months group (HR: 1.692, 95% CI: 1.354-2.115). Adhering to a three-month post-chemotherapy waiting period reduces infection and healthcare utilization risks for cancer patients receiving a COVID-19 vaccine.

Anti-COVID-19 Vaccination Alters the Menstrual Cycle and Dose Accumulation Enhances the Effect.

Background and Objectives: New investigations have detected an enhanced probability for women to develop menstrual cycle alterations after anti-COVID-19 vaccination. Moreover, given that the protective immunity provided by anti-COVID-19 vaccination appears to wane quickly, booster vaccination has been recommended. Nonetheless, whether adverse events arise from such repeated immunization has not been studied. Materials and Methods: We studied the incidence of menstrual cycle alterations, the quantity of menstrual cycle alterations per subject, and of altered menstrual cycles in nonpregnant women of fertile age after anti-COVID-19 vaccination in a cohort of vaccinated female subjects by the means of a standardized questionary that was applied via telephone calls each month. Subjects that received up to four doses were studied for 6 months after each dose. We calculated the odds ratio for enhanced incidence, as well as quadratic functions for the tendencies. A sensitivity analysis excluding subjects taking hormonal birth control and those with polycystic ovary syndrome was performed. Results: Anti-COVID-19 vaccination enhanced the probability to develop menstrual cycle alterations (OR 1.52, CI at 95% 1.2-1.8, p < 0.0001) and, interestingly, such a tendency was enhanced when subjects received more doses (R2 = 0.91). Furthermore, the same trends repeated for the quantity of alterations per subject, and of altered cycles. Such an effect was further demonstrated to be independent upon the vaccine brand being applied, the birth control status, and the diagnosis of polycystic ovary syndrome. Conclusions: Vaccination is the most cost-effective measure for primary prevention and is considered to be safe. Nonetheless, in this article, we show data that suggest that repeated vaccination of adult female subjects may lead to an enhanced incidence of menstrual cycle-related adverse events, quantity of alterations per subject, and altered cycles. We therefore think that the development of new vaccine formulations that produce longer-lasting immunity is of paramount importance to reduce the potential for dose accumulation-dependent enhanced risk.

Optic Neuritis After COVID-19 Vaccination: A Case Series and a Review of Literature.

The coronavirus disease (COVID-19) pandemic broke out in March 2020, causing tremendous damage to public health and more than 6 million deaths. After authorization for the emergency use of COVID-19 vaccines, various adverse events have been reported, including optic neuritis. COVID-19 vaccination was implemented in Taiwan in March 2021. We report patients who developed optic neuritis after COVID-19 vaccination at one university-affiliated tertiary hospital, between March 2021 and December 2022. We also provided a literature review of optic neuritis cases after COVID-19 vaccination. Five patients who developed optic neuritis after COVID-19 vaccination have been identified. Four brands of vaccine used were as follows: Moderna, Pfizer-BioNTech, Medigen, and Oxford AstraZeneca. Optic neuritis developed after the first dose of vaccination in 4 patients, whereas in 1 patient, it developed after the second shot. In the 3 patients with poor initial visual acuity, intravenous methylprednisolone pulse therapy achieved substantial improvement. Optic neuritis is a rare but potentially vision-threatening adverse effect of COVID-19 vaccination. We suggest early diagnosis and treatment to maximize visual outcomes.

A Profile of Influenza Vaccine Coverage for 2019-2020: Database Study of the English Primary Care Sentinel Cohort.

Innovation in seasonal influenza vaccine development has resulted in a wider range of formulations becoming available. Understanding vaccine coverage across populations including the timing of administration is important when evaluating vaccine benefits and risks. This study aims to report the representativeness, uptake of influenza vaccines, different formulations of influenza vaccines, and timing of administration within the English Primary Care Sentinel Cohort (PCSC). We used the PCSC of the Oxford-Royal College of General Practitioners Research and Surveillance Centre. We included patients of all ages registered with PCSC member general practices, reporting influenza vaccine coverage between September 1, 2019, and January 29, 2020. We identified influenza vaccination recipients and characterized them by age, clinical risk groups, and vaccine type. We reported the date of influenza vaccination within the PCSC by International Standard Organization (ISO) week. The representativeness of the PCSC population was compared with population data provided by the Office for National Statistics. PCSC influenza vaccine coverage was compared with published UK Health Security Agency's national data. We used paired t tests to compare populations, reported with 95% CI. The PCSC comprised 7,010,627 people from 693 general practices. The study population included a greater proportion of people aged 18-49 years (2,982,390/7,010,627, 42.5%; 95% CI 42.5%-42.6%) compared with the Office for National Statistics 2019 midyear population estimates (23,219,730/56,286,961, 41.3%; 95% CI 4.12%-41.3%; P<.001). People who are more deprived were underrepresented and those in the least deprived quintile were overrepresented. Within the study population, 24.7% (1,731,062/7,010,627; 95% CI 24.7%-24.7%) of people of all ages received an influenza vaccine compared with 24.2% (14,468,665/59,764,928; 95% CI 24.2%-24.2%; P<.001) in national data. The highest coverage was in people aged ≥65 years (913,695/1,264,700, 72.3%; 95% CI 72.2%-72.3%). The proportion of people in risk groups who received an influenza vaccine was also higher; for example, 69.8% (284,280/407,228; 95% CI 69.7%-70%) of people with diabetes in the PCSC received an influenza vaccine compared with 61.2% (983,727/1,607,996; 95% CI 61.1%-61.3%; P<.001) in national data. In the PCSC, vaccine type and brand information were available for 71.8% (358,365/498,923; 95% CI 71.7%-72%) of people aged 16-64 years and 81.9% (748,312/913,695; 95% CI 81.8%-82%) of people aged ≥65 years, compared with 23.6% (696,880/2,900,000) and 17.8% (1,385,888/7,700,000), respectively, of the same age groups in national data. Vaccination commenced during ISO week 35, continued until ISO week 3, and peaked during ISO week 41. The in-week peak in vaccination administration was on Saturdays. The PCSC's sociodemographic profile was similar to the national population and captured more data about risk groups, vaccine brands, and batches. This may reflect higher data quality. Its capabilities included reporting precise dates of administration. The PCSC is suitable for undertaking studies of influenza vaccine coverage.

Vaccination and Its Impact on Lung Involvement in COVID-19 Patients: A Retrospective Study in India.

Background COVID-19, caused by SARS-CoV-2, led to a global pandemic necessitating urgent vaccine development and deployment. By the end of 2020, several vaccines had reached their clinical trial endpoints. India, leveraging its pharmaceutical prowess, developed two primary vaccines: CoviShield® and Covaxin®. Despite the availability of these vaccines, vaccine hesitancy became a notable challenge. This study aimed to assess the correlation between vaccination status and lung involvement in COVID-19 patients, aiming to fortify trust in vaccines and enhance vaccine uptake in India. Methods This retrospective cross-sectional study analyzed data from 272 patients treated at a designated COVID-19 Care Center in Chennai, India, from May to July 2021. Patients were divided into vaccinated and unvaccinated groups, with vaccinated individuals further categorized based on the type and dose of vaccine received (CoviShield® or Covaxin®). Lung involvement was assessed through CT chest scans, and statistical analyses were performed to compare the severity of lung involvement across different groups. Results The vaccinated group demonstrated significantly lower mean lung involvement (28%) compared to the unvaccinated group (34.8%). Within vaccinated individuals, no significant differences were observed between different vaccine types and doses, suggesting a generalized protective effect of COVID-19 vaccination against severe lung involvement. Conclusion Vaccination against COVID-19 significantly reduces the severity of lung involvement among patients, irrespective of the vaccine brand or dose. This study reinforces the importance of vaccination in mitigating the impact of COVID-19 and supports ongoing vaccination efforts.

Economic Evaluation of COVID-19 Immunization Strategies: A Systematic Review and Narrative Synthesis.

This study aimed to systematically assess global economic evaluation studies on COVID-19 vaccination, offer valuable insights for future economic evaluations, and assist policymakers in making evidence-based decisions regarding the implementation of COVID-19 vaccination. Searches were performed from January 2020 to September 2023 across seven English databases (PubMed, Web of Science, MEDLINE, EBSCO, KCL-Korean Journal Dataset, SciELO Citation Index, and Derwent Innovations Index) and three Chinese databases (Wanfang Data, China Science and Technology Journal, and CNKI). Rigorous inclusion and exclusion criteria were applied. Data were extracted from eligible studies usinga standardized data collection form, with the reporting quality of these studies assessed using the Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022). Of the 40 studies included in the final review, the overall reporting quality was good, evidenced by a mean score of 22.6 (ranging from 10.5 to 28). Given the significant heterogeneity in fundamental aspects among the studies reviewed, a narrative synthesis was conducted. Most of these studies adopted a health system or societal perspective. They predominantly utilized a composite model, merging dynamic and static methods, within short to medium-term time horizons to simulate various vaccination strategies. The research strategies varied among studies, investigating different doses, dosages, brands, mechanisms, efficacies, vaccination coverage rates, deployment speeds, and priority target groups. Three pivotal parameters notably influenced the evaluation results: the vaccine's effectiveness, its cost, and the basic reproductive number (R0). Despite variations in model structures, baseline parameters, and assumptions utilized, all studies identified a general trend that COVID-19 vaccination is cost-effective compared to no vaccination or intervention. The current review confirmed that COVID-19 vaccination is a cost-effective alternative in preventing and controlling COVID-19. In addition, it highlights the profound impact of variables such as dose size, target population, vaccine efficacy, speed of vaccination, and diversity of vaccine brands and mechanisms on cost effectiveness, and also proposes practical and effective strategies for improving COVID-19 vaccination campaigns from the perspective of economic evaluation.

Seroepidemiological assessment of SARS-CoV-2 vaccine responsiveness and associated factors in the vaccinated community of the Casablanca-Settat Region, Morocco

Assessing the prevalence of SARS-CoV-2 IgG positivity through population-based serological surveys is crucial for monitoring COVID-19 vaccination efforts. In this study, we evaluated SARS-CoV-2 IgG positivity within a provincial cohort to understand the magnitude of the humoral response against the SARS-CoV-2 vaccine and to inform evidence-based public health decisions. A community-based cross-sectional seroprevalence study was conducted, involving 10,669 participants who received various vaccines (two doses for BBIBP-CorV/Sinopharm, Covishield vaccine, and Pfizer/BioNTech, and one dose for Johnson & Johnson's Janssen COVID-19 vaccine). The study spanned 16 provinces in the Casablanca-Settat region from February to June 2022, during which comprehensive demographic and comorbidity data were collected. We screened samples for the presence of IgG antibodies using the SARS-CoV-2 IgG II Quant assay, which quantifies antibodies against the receptor-binding domain (RBD) of the spike (S) protein, measured on the Abbott Architect i2000SR. The overall crude seroprevalence was 96% (95% CI: 95.6–96.3%), and after adjustment for assay performance, it was estimated as 96.2% (95% CI: 95.7–96.6). The adjusted overall seroprevalences according to vaccine brands showed no significant difference (96% for BBIBP-CorV/Sinopharm, 97% for ChAdOx1 nCoV-19/Oxford/AstraZeneca, 98.5% for BNT162b2/Pfizer-BioNTech, and 98% for Janssen) (p = 0.099). Participants of older age, female sex, those with a history of previous COVID-19 infection, and those with certain chronic diseases were more likely to be seropositive among ChAdOx1 nCoV-19/Oxford/AstraZeneca and BBIBP-CorV/Sinopharm vaccinee groups. Median RBD antibody concentrations were 2355 AU/mL, 3714 AU/mL, 5838 AU/mL, and 2495 AU/mL, respectively, after two doses of BBIBP-CorV/Sinopharm, ChAdOx1 nCoV-19/Oxford/AstraZeneca, BNT162b2/Pfizer-BioNTech, and after one dose of Janssen (p < 0.0001). Furthermore, we observed that participants vaccinated with ChAdOx1 nCoV-19/Oxford/AstraZeneca and BBIBP-CorV/Sinopharm with comorbid chronic diseases exhibited a more pronounced response to vaccination compared to those without comorbidities. In contrast, no significant differences were observed among Pfizer-vaccinated participants (p > 0.05). In conclusion, our serosurvey findings indicate that all four investigated vaccines provide a robust humoral immune response in the majority of participants (more than 96% of participants had antibodies against SARS-CoV-2). The BNT162b2 vaccine was found to be effective in eliciting a strong humoral response compared to the other three vaccines. However, challenges still remain in examining the dynamics and durability of immunoprotection in the Moroccan context.