National Vaccination Campaign Research Articles

Effectiveness of historical smallpox vaccination against mpox clade II in men in Denmark, France, the Netherlands and Spain, 2022.

BackgroundIn 2022, a global monkeypox virus (MPXV) clade II epidemic occurred mainly among men who have sex with men. Until early 1980s, European smallpox vaccination programmes were part of worldwide smallpox eradication efforts. Having received smallpox vaccine > 20 years ago may provide some cross-protection against MPXV.AimTo assess the effectiveness of historical smallpox vaccination against laboratory-confirmed mpox in 2022 in Europe.MethodsEuropean countries with sufficient data on case vaccination status and historical smallpox vaccination coverage were included. We selected mpox cases born in these countries during the height of the national smallpox vaccination campaigns (latest 1971), male, with date of onset before 1 August 2022. We estimated vaccine effectiveness (VE) and corresponding 95% CI for each country using logistic regression as per the Farrington screening method. We calculated a pooled estimate using a random effects model.ResultsIn Denmark, France, the Netherlands and Spain, historical smallpox vaccination coverage was high (80-90%) until the end of the 1960s. VE estimates varied widely (40-80%, I2 = 82%), possibly reflecting different booster strategies. The pooled VE estimate was 70% (95% CI: 23-89%).ConclusionOur findings suggest residual cross-protection by historical smallpox vaccination against mpox caused by MPXV clade II in men with high uncertainty and heterogeneity. Individuals at high-risk of exposure should be offered mpox vaccination, following national recommendations, regardless of prior smallpox vaccine history, until further evidence becomes available. There is an urgent need to conduct similar studies in sub-Saharan countries currently affected by the MPXV clade I outbreak.

Potential determinants of the decline in mpox cases in Belgium: A behavioral, epidemiological and seroprevalence study

ObjectivesThe 2022 mpox epidemic reached a peak in Belgium and the rest of Europe in July 2022, after which it unexpectedly subsided. This study investigates epidemiological, behavioral, and immunological factors behind the waning of the epidemic in Belgium. MethodsWe investigated temporal evolutions in the characteristics and behavior of mpox patients using national surveillance data and data from a prospective registry of mpox patients in the Institute of Tropical Medicine (Antwerp). We studied behavioral changes in the population at risk using a survey among HIV-preexposure prophylaxis (PrEP) users. We determined the seroprevalence of anti-orthopoxvirus antibodies among HIV-PrEP users across four-time points in 2022. ResultsMpox patients diagnosed at the end of the epidemic had less sexual risk behavior compared to those diagnosed earlier: they engaged less in sex at mass events, had fewer sexual partners, and were less likely to belong to the sexual network's central group. Among HIV-PrEP users there were no notable changes in sexual behavior. Anti-orthopoxvirus seroprevalence did not notably increase before the start of national vaccination campaigns. ConclusionThe observed changes in group immunity and behavior in the population at greater risk of exposure to mpox seem unable to explain the waning of the mpox epidemic. A change in the profile of mpox patients might have contributed to the decline in cases.

Hepatitis B virus infection among illegal drug users in Enugu State, Nigeria: prevalence, immune status, and related risk factors

IntroductionHepatitis B virus infection poses a global health challenge, particularly in low- and middle-income African countries. Illicit drug use exacerbates the problem, with drug users having a higher HBV infection risk and maintaining a quiet transmission pool. This study aimed to determine HBV infection prevalence, immune status, and risk factors among illegal drug users in Enugu State, Nigeria.Materials and methodsA cross-sectional study was conducted in Enugu State, using privileged access interviewer methods to enroll drug users. Pre-tested structured questionnaires were administered after informed consent was obtained. Blood samples were tested for HBsAg, HBsAb, HBeAg, HBeAb, and HBcAb using immunochromatographic rapid test kits. Statistical analysis was performed using SPSS version 25.ResultsOne hundred drug users were recruited into the study. Overall, 7% of the drug users had HBV infection. 61% were found to be susceptible to HBV infection, 15% showed serological evidence of immunity from HBV vaccination and 1% developed natural immunity from HBV exposure. Significant risk factors for HBV infection were age less than 20 years, young age (≤ 20 years) at drug initiation, being single, injecting drugs more than or equal to 20 times per month and injecting with used syringes.ConclusionThis study shows high intermediate endemicity of HBV infection among drug users, low vaccination uptake, and high susceptibility to HBV infection. This calls for the urgent inclusion of drug users in national HBV vaccination campaigns and the adoption of the World Health Organization’s recommendations on the prevention of viral hepatitis among people who inject drugs.

Assessing the impact of Australia's mass vaccination campaigns over the Delta and Omicron outbreaks.

The Australian Government implemented a national vaccination campaign against COVID-19 beginning February 22, 2021. The roll-out was criticised for being delayed relative to many high-income countries, but high levels of vaccination coverage were belatedly achieved. The large-scale Omicron outbreak in January 2022 resulted in a massive number of cases and deaths, although mortality would have been far higher if not for vigorous efforts to rapidly vaccinate the entire population. The impact of the vaccination coverage was assessed over this extended period. We considered NSW, as the Australian jurisdiction with the highest quality data for our purposes and which still reflected the national experience. Weekly death rates were derived among individuals aged 50+ with respect to vaccine status between August 8, 2021 and July 9, 2022. We evaluated deaths averted by the vaccination campaign by modelling alternative counterfactual scenarios based on a simple data-driven modelling methodology presented by Jia et al. (2023). Unvaccinated individuals had a 7.7-fold greater mortality rate than those who were fully vaccinated among people aged 50+, which rose to 11.2-fold in those who had received a booster dose. If NSW had fully vaccinated its ~2.9 million 50+ residents earlier (by July 28, 2021), only 440 of the total 3,495 observed 50+ deaths would have been averted. Up to July 9, 2022, the booster campaign prevented 1,860 deaths. In the absence of a vaccination campaign, ~21,250 COVID-19 50+ deaths (conservative estimate) could have been expected in NSW i.e., some 6 times the actual total. We also find the methodology of Jia et al. (2023) can sometimes significantly underestimate that actual number. The Australian vaccination campaign was successful in reducing mortality over 2022, relative to alternative hypothetical vaccination scenarios. The success was attributable to the Australian public's high levels of engagement with vaccination in the face of new SARS-COV-2 variants, and because high levels of vaccination coverage (full and booster) were achieved in the period shortly before the major Omicron outbreak of 2022.

Impact of the COVID-19 pandemic, its related social restriction measures and vaccination campaign on emergency department attendances for epileptic seizures: An interrupted time-series analysis

AimTo investigate the impact of the outbreak of the COVID-19 pandemic, its related social restriction measure (national lockdown) and vaccination campaign on emergency department (ED) accesses for epileptic seizures. MethodsRetrospective observational analysis conducted on a consecutive cohort of patients who sought medical care at the ED of the General Hospital of Merano, Italy, from January 1, 2015, to December 31, 2021. We investigated the monthly ED attendances for epileptic seizures between the periods before and after the outbreak of the COVID-19 pandemic and the national lockdown (March 2020) using an interrupted time-series analysis with data standardized for 1000 accesses/month. As a further temporal cutoff, we used the start of the national vaccination campaign. ResultsBetween January 1, 2015, and December 31, 2021, a total of 415,005 ED attendances were recorded; 1,254 (0.3 %) were due to epileptic seizures. No significant difference was found in the rate of standardized ED accesses for epileptic seizures in March 2020 (time point of interest) to the pre-pandemic trend (0.33/1000; 95 %CI: −1.05 to 1.71; p = 0.637). Similarly, there was no difference between the pre- and post-pandemic trends (-0.02/1000; 95 %CI: −0.11 to 0.06; p = 0.600). When adopting January 2021 as time point of interest, we found no difference to the pre-vaccination trend (0.83/1000; 95 %CI: −0.48 to 2.15), and no difference in the pre- and post-vaccination trends (-0.12/1000; 95 %CI: −0.27 to 0.04). ConclusionsThe COVID-19 pandemic and its related social restrictions (lockdown), as well as the COVID-19 national vaccination campaign, had little impact on ED accesses for epileptic seizures.

The role of COVID-19 vaccines in preventing post-COVID-19 thromboembolic and cardiovascular complications

ObjectiveTo study the association between COVID-19 vaccination and the risk of post-COVID-19 cardiac and thromboembolic complications.MethodsWe conducted a staggered cohort study based on national vaccination campaigns using electronic health records...

COVID-19 vaccine hesitancy in KwaZulu-Natal, South Africa: A survey of unvaccinated adults.

Concerns and misconceptions surrounding coronavirus disease 2019 (COVID-19) vaccines may account for vaccine hesitancy and low uptake. To determine prevalence of COVID-19 vaccine hesitancy, vaccine-related misconceptions, and predictors of vaccine hesitancy among South Africans. Community setting in five districts in KwaZulu- Natal province. Between August 20, 2021, and September 27, 2021, we conducted a cross-sectional survey, interviewing 300 unvaccinated adults amid the national vaccination campaign. Predictors of hesitancy were identified through multivariable logistic regression analysis. Participants had a median age of 29 years (IQR: 23-39), 86.7% were Black African, 63.2% were male, 53.3% resided in rural communities, and 59.3% (95% CI: 53.8% - 64.9%) were classified as vaccine hesitant. The primary reason for not vaccinating was a lack of trust in the vaccine (62.1%). Factors associated with reduced vaccine hesitancy included age (participants aged 35-49 years: OR: 0.28, 95% CI: 0.18-0.64, p = 0.003; participants over 50 years: OR: 0.18, 95% CI: 0.07-0.47, p = 0.0004), previous COVID-19 infection (OR: 0.31, 95% CI: 0.11-0.87, p = 0.03), and receiving vaccine information from healthcare workers (OR: 0.32, 95% CI: 0.10-1.0, p = 0.05). Unemployed (OR: 2.14, 95% CI: 1.1-4.2, p = 0.03) and self-employed individuals (OR: 2.98, 95% CI: 1.27-7.02, p = 0.01) were more likely to be vaccine hesitant. COVID-19 vaccine hesitancy rates are high in KwaZulu-Natal. Uptake could be enhanced by healthcare workers leading information campaigns with messages targeting younger individuals, the unemployed, and the self-employed. This survey provides evidence to improve COVID-19 vaccination uptake in South Africa.

Serological investigation of vaccine-induced antibodies for measles, rubella, and yellow fever viruses in children vertically exposed to Zika virus or with down syndrome.

Vaccination schedules, as well as their effectiveness and contraindications, need to be evaluated regularly, especially in specific situations. Congenital Zika Syndrome (CZS) is a severe condition that results in extensive functional and neurological impairment of fetuses and newborns due to Zika virus tropism for fetal neural progenitor cells. Down Syndrome (DS) is the leading genetic cause of intellectual disability. The immune impairment in DS has already been described, but little is known about the immune response of CZS children. Thus, CZS and DS are specific conditions that can be considered for a reassessment of the available immunizations. Here, we carried out serological analyses of attenuated vaccines-induced antibodies for measles, rubella, and yellow fever viruses in children aged 2-7, grouped into asymptomatic controls, DS children, and CZS children. Plasma samples were taken, and vaccination records were compiled during clinical follow-up. Enzymatic immunoassays for quantifying anti-measles and anti-rubella IgG were performed to assess the response to the Measles, Mumps, and Rubella (MMR) vaccine. Plaque Reduction Neutralization Test (PRNT) was performed to investigate neutralizing antibodies in response to the Brazilian vaccine strain of yellow fever (YF-17DD). We highlight similar levels of anti-measles IgG and neutralizing antibodies for YF-17DD among CZS, DS, and asymptomatic children, although low positivity of measles data was seen in the three groups. In DS children, the 2-4-year-old group had an increased level of anti-measles IgG compared to the older group of children aged five to seven years. Lower anti-rubella IgG levels were observed in CZS and DS children compared to asymptomatic children. For anti-rubella IgG, the good performance of vaccination in asymptomatic children is due to younger ones rather than older ones. There were no reports of adverse events after the use of the MMR and YF-17DD indicating that CZS and DS could continue to receive these vaccines, but our data draws attention to the necessity of monitoring the vaccination response in CZS and DS children over time and the possible need to adhere to national measles vaccination campaigns. Scientific research needs to continue to help develop appropriate CZS and DS health guidelines.

The Brazilian vaccine divide: How some municipalities were left behind in the Covid-19 vaccine coverage.

This study aims to assess the progress of geographic, socioeconomic, and demographic disparities in Covid-19 vaccination coverage in Brazil over the first two years of the vaccination campaign. Data from the National Immunization Program Information System were used to estimate covid-19 vaccine coverage. Brazilian municipalities were divided into two groups based on their vaccine coverage for the booster dose. The first group comprised 20% of municipalities with the lowest coverage, while the second group (80% of municipalities) had higher coverage. The analysis was conducted separately for four age groups: 5-11, 12-17, 18-59, and 60+. Explanatory variables included socioeconomic and health services indicators. Crude and adjusted logistic regression models were used to estimate the probability of a municipality being among those with the worst vaccination coverage according to the categories of exploratory variables. Between January/2021 and December/2022, Brazil administered 448.2 million doses of the covid-19 vaccine. The booster vaccination coverage varied from 24.8% among adolescents to 79.7% among the elderly. The difference between the group with the highest and lowest coverage increased during the national vaccination campaign. Municipalities with lower education levels, higher proportion of Black population, higher Gini index, and worse health service indicators had a greater likelihood of having lower vaccination coverage. High and increasing levels of inequality in Covid-19 vaccination were observed in Brazil across all age groups during the vaccination campaign in 2021-2022.

Incidence and risk prediction of post-Covid-19 cardiovascular disease in the general population: a multivariable prediction model development and validation study

Abstract Background Previous studies showed that relative risks of various cardiovascular events are increased after Covid-19, even in non-hospitalized individuals. The global burden of post-Covid-19 cardiovascular disease is large and not (yet) hospitalized Covid-19 infected adults may represent a potential target for prevention strategies to mitigate this burden. However, good estimates of individual absolute risks in the general population and risk stratification models are lacking, yet pivotal to assess its impact and direct health care policy. Purpose This study aimed to assess the absolute risk of post-Covid-19 cardiovascular events in the general population, and subsequently explore individual risk prediction in this domain. Methods Covid-19 diagnosed adults were identified from the United Kingdom’s Clinical Practice Research Datalink Aurum, a primary care electronic healthcare database. We assessed 180-day incidence rates of atherosclerotic events (acute coronary syndrome, stroke and transient ischaemic accident), venous thrombo-embolic events (pulmonary embolism and deep venous thrombosis), and newly diagnosed atrial fibrillation and heart failure. Multivariable logistic regression models using elastic net penalization were developed on a cohort of 220,751 adults with Covid-19 before 1 December 2020 (before the start of national vaccination campaigns). Candidate predictors included age, sex, body mass index, smoking, medical history and medication. Three models were fit for each endpoint, with increasing numbers of predictors. All models were validated in (1) 138,034 vaccinated and (2) 503,404 non-vaccinated adults with a first Covid-19 diagnosis after 1 December 2020. We evaluated discriminative and calibration performance upon internal cross-validation and in both validation cohorts. Results Post-Covid-19 cardiovascular event incidences ranged from 13 (venous thromboembolic events) down to 4 (heart failure de novo) per 1000 person-years. Incidences were relatively increased up to 50 days after Covid-19 infection. However, on an absolute scale, individual risks were very low: only less than one in twenty adults with Covid-19 had a predicted 180-day risk larger than 1% and these mainly included individuals aged 60 years or older. Even though the best models had high discriminative performance (AUC > 0.90), rare outcomes complicated predictive performance and calibration. Conclusions Risks of atherosclerotic events, venous thromboembolic events, and newly diagnosed atrial fibrillation and heart failure are increased after Covid-19 infection in the general population, notably within the first 50 days after infection and in individuals aged 60 years or older. However, individual risks are too low to be predictive or helpful to guide individual risk management. Risk mitigation strategies should therefore be aimed at population-based prevention (such as increasing vaccination uptake) and at individual management of Covid-19 hospitalized patients.Graphical abstractPredicted 180-day risk after Covid-19

Online on the frontline: A longitudinal social media analysis of UK healthcare workers’ attitudes to COVID-19 vaccines using the 5C framework

This paper explores vaccine hesitancy among healthcare workers (HCWs) in the UK, where different COVID-19 vaccines were being rolled out through a national vaccination campaign from 2020 to 2022, consisting of a first and second dose programme. Through a mixed-method approach using qualitative discourse analysis and network analysis of Twitter data, we assessed HCW perceptions and views about the administration and delivery of COVID-19 vaccines in the United Kingdom (UK). We were also interested in exploring HCWs' personal experiences and attitudes towards taking COVID-19 vaccines themselves. We drew upon sociology, ethics, communication studies and used research methods concentrating on social media and media analysis. By employing the ‘5C framework’ of ‘confidence, complacency, constraints, calculation, and collective responsibility’ we evaluated a longitudinal selection of tweets to capture relevant factors driving vaccination views and behaviours among HCWs. We found differing positions expressed about COVID-19 vaccines and policy during the first dose compared with the second, through a drop in confidence compounded by supply and access issues, as well the news of a vaccine mandate for HCWs by the UK government in 2021. HCWs asked calculation questions to the community or brought forward competing pieces of information about vaccine policy and guidelines. Constraint levels in access issues were noted, especially for those with work and caregiving responsibilities, and student nurses found they did not have equal vaccination access. HCWs also displayed collective responsibility on social platforms to both encourage vaccination and express concerns through the organisation of social action against vaccine mandates.

Navigating economic turmoil: Chilean businesses during COVID-19 lockdowns and vaccine rollouts

ObjectivesThis study evaluates the effects of COVID-19 lockdowns, differentiated by their stringency, on the sales of Chilean businesses across various size categories and industries throughout 2020 and 2021. It also explores the role of the vaccination campaign and the implementation of the Mobility Pass in mitigating the negative economic effects of stringent containment measures. MethodsThe study uses administrative data from the Chilean Internal Revenue Service (SII), examining sales across different business sizes and industries, from March 2020 to December 2021. Through an econometric analysis, we estimate the effects of lockdowns on business sales during two distinct periods: initial reliance on dynamic non-pharmaceutical interventions (NPIs) pre-vaccine, and a subsequent stage characterized by high vaccine uptake and reduced NPI stringency. ResultsLockdowns significantly reduced sales across all business sizes and most industries during the first period, with microenterprises and certain service sectors experiencing the highest decline. The national vaccination campaign and the introduction of the Mobility Pass in the second period appears to have mitigated the negative effects of lockdowns, primarily benefiting micro and small firms. ConclusionsThe study highlights the trade-offs between health and economic outcomes during the pandemic, stressing the importance to alleviate mobility restrictions post-vaccine rollout to ease the economic strain on businesses. The findings call for targeted support measures for MSMEs and vulnerable industries affected by NPIs.

COVID-19 vaccine effectiveness against hospitalizations in Paraguay, May 2021—April 2022: A test-negative design

BackgroundVaccine effectiveness (VE) estimates vary by population characteristics and circulating variants. North America and Europe have generated many COVID-19 VE estimates but relied heavily on mRNA vaccines. Fewer estimates are available for non-mRNA vaccines and from Latin America. We aimed to estimate the effectiveness of several COVID-19 vaccines in preventing SARS-CoV-2-associated severe acute respiratory infection (SARI) in Paraguay from May 2021 to April 2022. MethodsUsing sentinel surveillance data from four hospitals in Paraguay, we conducted a test-negative case-control study to estimate COVID-19 vaccine effectiveness against SARI by vaccine type/brand and period of SARS-CoV-2 variant predominance (Gamma, Delta, Omicron). We used multivariable logistic regression adjusting for month of symptom onset, age group, and presence of ≥1 comorbidity to estimate the odds of COVID-19 vaccination in SARS-CoV-2 test-positive SARI case-patients compared to SARS-CoV-2 test-negative SARI control-patients. ResultsOf 4,229 SARI patients, 2,381 (56%) were SARS-CoV-2-positive case-patients and 1,848 (44%) were SARS-CoV-2-negative control-patients. A greater proportion of case-patients (73%; 95% CI: 71–75) than of control-patients (40%; 95% CI: 38–42) were unvaccinated. During the Gamma variant-predominant period, VE estimates for partial vaccination with mRNA vaccines and Oxford/AstraZeneca Vaxzevria were 90.4% (95% CI: 66.4–97.6) and 52.2% (95% CI: 25.0–69.0), respectively. During the Delta variant-predominant period, VE estimates for complete vaccination with mRNA vaccines, Oxford/AstraZeneca Vaxzevria, or Gamaleya Sputnik V were 90.4% (95% CI: 74.3–97.3), 83.2% (95% CI: 67.8–91.9), and 82.9% (95% CI: 53.0–95.2), respectively. The effectiveness of all vaccines declined substantially during the Omicron variant-predominant period. ConclusionsThis study contributes to our understanding of COVID-19 VE in Latin America and to global understanding of vaccines that have not been widely used in North America and Europe. VE estimates from Paraguay can parameterize models to estimate the impact of the national COVID-19 vaccination campaign in Paraguay and similar settings.

Capturing Emerging Experiential Knowledge for Vaccination Guidelines Through Natural Language Processing: Proof-of-Concept Study.

Experience-based knowledge and value considerations of health professionals, citizens, and patients are essential to formulate public health and clinical guidelines that are relevant and applicable to medical practice. Conventional methods for incorporating such knowledge into guideline development often involve a limited number of representatives and are considered to be time-consuming. Including experiential knowledge can be crucial during rapid guidance production in response to a pandemic but it is difficult to accomplish. This proof-of-concept study explored the potential of artificial intelligence (AI)-based methods to capture experiential knowledge and value considerations from existing data channels to make these insights available for public health guideline development. We developed and examined AI-based methods in relation to the COVID-19 vaccination guideline development in the Netherlands. We analyzed Dutch messages shared between December 2020 and June 2021 on social media and on 2 databases from the Dutch National Institute for Public Health and the Environment (RIVM), where experiences and questions regarding COVID-19 vaccination are reported. First, natural language processing (NLP) filtering techniques and an initial supervised machine learning model were developed to identify this type of knowledge in a large data set. Subsequently, structural topic modeling was performed to discern thematic patterns related to experiences with COVID-19 vaccination. NLP methods proved to be able to identify and analyze experience-based knowledge and value considerations in large data sets. They provide insights into a variety of experiential knowledge that is difficult to obtain otherwise for rapid guideline development. Some topics addressed by citizens, patients, and professionals can serve as direct feedback to recommendations in the guideline. For example, a topic pointed out that although travel was not considered as a reason warranting prioritization for vaccination in the national vaccination campaign, there was a considerable need for vaccines for indispensable travel, such as cross-border informal caregiving, work or study, or accessing specialized care abroad. Another example is the ambiguity regarding the definition of medical risk groups prioritized for vaccination, with many citizens not meeting the formal priority criteria while being equally at risk. Such experiential knowledge may help the early identification of problems with the guideline's application and point to frequently occurring exceptions that might initiate a revision of the guideline text. This proof-of-concept study presents NLP methods as viable tools to access and use experience-based knowledge and value considerations, possibly contributing to robust, equitable, and applicable guidelines. They offer a way for guideline developers to gain insights into health professionals, citizens, and patients' experience-based knowledge, especially when conventional methods are difficult to implement. AI-based methods can thus broaden the evidence and knowledge base available for rapid guideline development and may therefore be considered as an important addition to the toolbox of pandemic preparedness.

Comparison of awareness, attitudes and knowledge on human papilloma virus vaccination in Singapore: 2019 versus 2013.

This study aimed to assess the changes in the awareness, attitudes and knowledge regarding human papillomavirus (HPV) vaccination among the local population. The secondary aims were to identify barriers and to evaluate the effectiveness of national HPV vaccination campaigns over a six-year period in Singapore. We conducted and compared two cross-sectional surveys in 2013 and 2019 among female participants attending a general gynaecology clinic. A total of 597 participants completed the survey in 2013 and 2019. The participants were comparable in their race, marital status, educational level, occupation and monthly household income. Knowledge scores for cervical cancer and HPV infection showed significant improvement from 2013 to 2019. There was no significant difference in knowledge scores for HPV vaccination, which resulted in similar uptake of the HPV vaccine. Age, educational level and knowledge of HPV vaccine were significant predictors of acceptance of the HPV vaccine. The top two reasons for declining the HPV vaccine were the lack of knowledge and cost, as noted in the 2019 survey. The Singapore government's efforts to improve cervical cancer awareness through national campaigns and policy changes have led to an improvement in knowledge of HPV infection. However, this has not translated into improvements in the vaccine acceptance rates. The decision for vaccine uptake is complex, and there are multiple factors to be addressed to ensure cost-effective implementation of the strategies. Our study highlights the need for effective dissemination of vaccine information, additional subsidies and consideration of a mandatory school-based vaccination programme.

Exploring COVID-19 education to support vaccine confidence amongst the general adult population with special considerations for healthcare and long-term care staff: A scoping review.

Despite the demonstrated efficacy of approved COVID-19 vaccines, high levels of hesitancy were observed in the first few months of the COVID-19 vaccines' rollout. Factors contributing to vaccine hesitancy are well-described in the literature. Among the various strategies for promoting vaccine confidence, educational interventions provide a foundationally and widely implemented set of approaches for supporting individuals in their vaccine decisions. However, the evidence around the measurable impact of various educational strategies to improve vaccine confidence is limited. We conducted a scoping review with the aim of exploring and characterizing educational interventions delivered during the pandemic to support COVID-19 vaccine confidence in adults. We developed a search strategy with a medical information scientist and searched five databases, including Ovid MEDLINE and Web of Science, as well as grey literature. We considered all study designs and reports. Interventions delivered to children or adolescents, interventions on non-COVID-19 vaccines, as well as national or mass vaccination campaigns without documented interaction(s) between facilitator(s) and a specific audience were excluded. Articles were independently screened by three reviewers. After screening 4602 titles and abstracts and 174 full-text articles across two rounds of searches, 22 articles met our inclusion criteria. Ten additional studies were identified through hand searching. Data from included studies were charted and results were described narratively. We included 32 studies and synthesized their educational delivery structure, participants (i.e., facilitators and priority audience), and content. Formal, group-based presentations were the most common type of educational intervention in the included studies (75%). A third of studies (34%) used multiple strategies, with many formal group-based presentations being coupled with additional individual-based interventions (29%). Given the novelty of the COVID-19 vaccines and the unique current context, studies reported personalized conversations, question periods, and addressing misinformation as important components of the educational approaches reviewed. Various educational interventions were delivered during the COVID-19 pandemic, with many initiatives involving multifaceted interventions utilizing both formal and informal approaches that leveraged community (cultural, religious) partnerships when developing and facilitating COVID-19 vaccine education. Train-the-trainer approaches with recognized community members could be of value as trust and personal connections were identified as strong enablers throughout the review.

Beyond the numbers: An in-depth look at Cameroon's fifth national COVID-19 vaccination campaign through geographical and gender lenses

BackgroundCameroon has been struggling with low Covid-19 vaccination coverage, with only 4.5 % of the population receiving the primary series as of November 2022. The COVID-19 Vaccine Delivery Partnership (CoVDP) conducted a high-level mission to Cameroon to assess progress and advocate for actions to address bottlenecks. The objective of the mission was to administer at least 3,000,000 doses of vaccines during the 5th Mass vaccination campaign. This study examines the factors contributing to the success of the campaign and uses a geographical and gender lens to assess the results. MethodsThe study is a secondary analysis of data from the DHIS2 collected during the 5th mass vaccination campaign for Covid-19. Descriptive statistics were used to assess coverages per location and gender expressed in OR. sccess factors, and chi-squared tests were used to assess differences in vaccine distribution across regions and by gender. ResultsThis 5th vaccination campaign benefitted from a strong political commitment facilitated by CoVDP's mission, international support, collaboration, planning, supervision, and demand generation.The campaign recorded 2 019 118 administered vaccine doses, a staggering 46-fold increase in vaccinated individuals relative to the first round, with vaccination coverage reaching 10.1 % of the general population. However, the study reveals regional and gender disparities in vaccination coverage. Men had higher odds of being vaccinated than women in the three Sahel regions. Among individuals with comorbidities, the national coverage rate was only 14 %, and the Far North and East regions exhibited the lowest coverage rates. Janssen was the most used vaccine, and the total AEFI cases reported were 2 per 1000 vaccine doses. ConclusionThe 5th COVID-19 vaccination campaign in Cameroon saw a strong political commitment and was the most successful so far. Despite the gains, there was gender disparity in coverage in some regions. It is important to continue the established momentum, ensure equitable access in the Sahel regions, and reach high-priority groups with primary series and booster doses.

Seroprevalence of COVID-19 in Oran: Cross-Sectional Study.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was introduced in Algeria in March 2020. This study aimed to estimate the seroprevalence of SARS-CoV-2 infection in Oran, Algeria, and to identify factors associated with seropositivity. This was a cross-sectional seroprevalence study conducted between 7 and 20 January 2021 across all 26 municipalities in the province of Oran. The study employed a random cluster sampling technique stratified by age and sex to select participants from households, who were then administered a rapid serological test. The overall seroprevalence and specific seroprevalences by municipality were calculated, and the number of COVID-19 cases in Oran was estimated. The correlation between population density and seroprevalence was also examined. Among the participants, 422 (35.6%; 95% confidence interval [CI], 32.9 to 38.4) had a positive serological test for SARS-CoV-2, and eight municipalities had seroprevalence rates above 73%. We found a strong positive correlation between population density and seroprevalence (r = 0.795, P < 0.001), indicating that areas with higher population density had higher numbers of positive COVID-19 cases. Our study provides evidence of a high seroprevalence of SARS-CoV-2 infection in Oran, Algeria. The estimated number of cases based on seroprevalence is much higher than the number of cases confirmed by PCR. Our findings suggest that a large proportion of the population has been infected with SARS-CoV-2, highlighting the need for continued surveillance and control measures to prevent further spread of the virus. IMPORTANCE This is the first and only seroprevalence study of COVID-19 conducted in the general population in Algeria prior to the national vaccination campaign against COVID-19. The significance of this study lies in its contribution to our understanding of the spread of the virus in the population before the implementation of the vaccination program.

EPH203 Patients Characteristics, Vaccine Uptake, Healthcare Resource Utilization and Costs Associated with Acute COVID-19 during the Omicron Predominant Period in Brazil: A Nationwide Database Study

The coronavirus disease 2019 (COVID-19) pandemic has imposed significant burden on Brazil’s health system. The present study aims to describe patients’ demographic and clinical characteristics, vaccine uptake and assess healthcare resource utilization (HCRU) and costs associated with acute COVID-19 in Brazil during the Omicron predominant period. A population-based retrospective study was conducted using the National Health Data Network (RNDS), National Vaccination Campaign against COVID-19 data and surveillance data in public setting. Individuals with positive COVID-19 test results between January-April 2022 were identified. Patients’ demographics, comorbidities, vaccination status, HCRU for those who were admitted to hospitals and their associated costs were described by age groups. A total of 8,160,715 COVID-19 cases were identified and 2.7% were aged <5 years, 11.6% were 5-19 years, 76.9% were 20-64 years and 8.7% were ≥ 65 years. The presence of comorbidity was 23.1% with a higher prevalence of comorbidities in the elderly (61.8% for 65-74 years and 71.2% for ≥75 years). Regarding COVID -19 vaccination uptake, among those aged ≤19 years, 20-64 years and ≥65 years, 40.6%, 86.5% and 92.2% had primary series, respectively. Among adults, the booster uptake was 47.3% and 75.8% for those aged 20-64 years and ≥ 65 years, respectively. Among those with confirmed COVID-19, regardless of vaccination status, 87% were being symptomatic and 1.7% were hospitalized (3.8% in aged <5 years, 4.2% in 5-19 years, 34.3% in 20-64 years and 57.6% in ≥ 65 years). Among hospitalized patients, 32,6% were admitted to ICU and 80% required mechanical ventilation support. The average cost per day in normal wards and ICU without ventilation was R$291,89 and R$923,90, respectively. Our results quantify the public health and economic burden of COVID-19 in Brazil, suggesting substantial healthcare resources required to manage the COVID-19 pandemic.

Effectiveness of JYNNEOS Vaccine Against Diagnosed Mpox Infection - New York, 2022.

In 2022, an international Monkeypox virus outbreak, characterized by transmission primarily through sexual contact among gay, bisexual, and other men who have sex with men (MSM), resulted in 375 monkeypox (mpox) cases in the state of New York outside of New York City (NYC).*,† The JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic), licensed by the U.S. Food and Drug Administration (FDA) against mpox as a 2-dose series, with doses administered 4 weeks apart,§ was deployed in a national vaccination campaign.¶ Before this outbreak, evidence to support vaccine effectiveness (VE) against mpox was based on human immunologic and animal challenge studies (1-3). New York State Department of Health (NYSDOH) conducted a case-control study to estimate JYNNEOS VE against diagnosed mpox in New York residents outside of NYC, using data from systematic surveillance reporting. A case-patient was defined as a man aged ≥18 years who received a diagnosis of mpox during July 24-October 31, 2022. Contemporaneous control patients were men aged ≥18 years with diagnosed rectal gonorrhea or primary syphilis and a history of male-to-male sexual contact, without mpox. Case-patients and control patients were matched to records in state immunization systems. JYNNEOS VE was estimated as 1 - odds ratio (OR) x 100, and JYNNEOS vaccination status (vaccinated versus unvaccinated) at the time of diagnosis was compared, using conditional logistic regression models that adjusted for week of diagnosis, region, patient age, and patient race and ethnicity. Among 252 eligible mpox case-patients and 255 control patients, the adjusted VE of 1 dose (received ≥14 days earlier) or 2 doses combined was 75.7% (95% CI = 48.5%-88.5%); the VE for 1 dose was 68.1% (95% CI = 24.9%-86.5%) and for 2 doses was 88.5% (95% CI = 44.1%-97.6%). These findings support recommended 2-dose JYNNEOS vaccination consistent with CDC and NYSDOH guidance.