Hepatitis A GBM strain (adsorbed) / Typhoid polysaccharide vaccine suspension for injection 1ml pre-filled syringes

BackgroundImmunization is a highly effective intervention for controlling over 20 life-threatening infectious diseases, significantly reducing both morbidity and mortality rates. One notable achievement in vaccination efforts was the global eradication of smallpox, which the World Health Assembly declared on 8 May 1980. Additionally, there has been a remarkable 99.9% reduction in wild poliovirus cases since 1988, decreasing from more than 350,000 cases that year to just 30 cases in 2022.ObjectivesThe objective of this review was to assess the effects of various interventions designed to increase vaccination uptake among adults.Search methodsA thorough search was conducted in the CENTRAL, Embase Ovid, Medline Ovid, PubMed, Web of Science, and Global Index Medicus databases for primary studies. This search was conducted in August 2021 and updated in November 2024.Selection criteriaRandomized trials were eligible for inclusion in this review, regardless of publication status or language.Data analysisTwo authors independently screened the search outputs to select potentially eligible studies. Risk ratios (RR) with 95% confidence intervals (CI) were calculated for each randomized controlled trial (RCT). A meta-analysis was conducted using a random-effects model, and the quality of the evidence was assessed using the GRADE approach.Main resultsA total of 35 randomized controlled trials met the inclusion criteria and were included in this review, with the majority conducted in the United States. The interventions targeted adults aged 18 and older who were eligible for vaccination, involving a total of 403,709 participants. The overall pooled results for interventions aimed at increasing influenza vaccination showed a risk ratio of 1.41 (95% CI: 1.15, 1.73). Most studies focused on influenza vaccination (18 studies), while the remaining studies examined various other vaccines, including those for hepatitis A, COVID-19, hepatitis B, pneumococcal disease, tetanus, diphtheria, pertussis (Tdap), herpes zoster, and human papillomavirus (HPV). The results indicate that letter reminders were slightly effective in increasing influenza vaccination uptake compared to the control group (RR: 1.75, 95% CI: 0.97, 1.16; 6 studies; 161,495 participants; low-certainty evidence). Additionally, participants who received education interventions showed increased levels of influenza vaccination uptake compared to those in the control group (RR: 1.88, 95% CI: 0.61, 5.76; 3 studies; 1318 participants; low-certainty evidence). Furthermore, tracking and outreach interventions also led to an increase in influenza vaccination uptake (RR: 1.87, 95% CI: 0.78, 4.46; 2 studies; 33,752 participants; low-certainty evidence).ConclusionsLetter reminders and educational interventions targeted at recipients are effective in increasing vaccination uptake compared to control groups.

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ABSTRACT Background Randomized clinical trials provide the highest standard of evidence about vaccine efficacy. Modelling exercises such as in evidence synthesis and health economic models where efficacy estimates are combined with other data to obtain effectiveness and cost-effectiveness estimates help inform policy decisions. The main challenge with such sensitivity analyses is in deciding on which assumptions to model. Purpose To identify plausible ranges for differential vaccine efficacy across high- and low-income settings. Data Sources and Study Selection MEDLINE, EMBASE, clinicaltrials.gov, and the World Health Organization International Clinical Trials Registry Platform (WHO-ICTRP) were searched for multi-site randomized clinical trials of bacterial and viral vaccines for the period of 01/01/1990 to 31/12/2020. Articles were restricted to those where at least one trial had included a low- or lower-middle-income setting, published in English, and conducted in humans. Methods A Bayesian random-effects meta-analysis was used to estimate the difference in vaccine efficacy in high-(high or upper middle) and low-(low or lower middle) income settings. A single hierarchical model that included all trials was used so that the degree to which estimates of vaccine efficacy against different diseases influenced one another was estimated from the observed data. Results Across 65 eligible trials (37 high-income, 21 low-income, and 7 both) covering 7 pathogens, only one trial reported efficacy estimates stratified by setting. Trials were similar in terms of design across settings. There was evidence of heterogeneity by vaccine target, typhoid vaccine demonstrated higher vaccine efficacy in low-income settings than in high-income settings but for all other vaccines, the point estimates indicated efficacy was lower in low-income settings; however, all credible intervals crossed the null. Conclusions The percentage of trials in low-income settings poorly reflects the burden of disease experienced in low-income settings. While there is evidence of lower vaccine efficacy in low-income settings relative to high-income settings, the credible intervals were very wide. Vaccine efficacy trials should report treatment effects stratified by settings.

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BackgroundIndia is one of the countries with a high typhoid fever burden. In 2022, the National Technical Advisory Group on Immunisation recommended including the typhoid conjugate vaccine (TCV) in the Universal Immunisation Programme. In this study, we aimed to estimate the 2023 burden of typhoid fever and its antimicrobial resistance (AMR) to inform targeted vaccine introduction strategies.MethodsWe used a decision tree model to estimate typhoid cases, hospitalisations, complications, and deaths. Incidence and clinical parameters were derived from a multicentre Indian study, with state-wise AMR prevalence from a systematic review. Two co-primary and four alternative scenarios were presented to validate the robustness of the findings.FindingsWe estimated 4.9 million (95% UI: 4.4-5.6) typhoid cases and 7850 (4300-14,900) deaths in India in 2023. Of 730,000 (534,000-970,000) hospitalisations, 600,000 (435,000-799,000; 82%) were attributable to fluoroquinolone-resistant. Under primary scenario A, children InterpretationFluoroquinolone-resistance drives a large share of typhoid-related hospitalisations and deaths, especially in children under five and in high-burden states of India. Targeted TCV introduction, with broader age coverage among children, would maximise impact.FundingWISE programme; Vaccine Impact Modelling Consortium; Japan Agency for Medical Research and Development.

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Hydro-meteorological and geological disasters can pose serious harm to community health, such as an increased risk of infectious diseases and related mortality. We conducted a scoping review to compile the available literature on the effects of hydro-meteorological and geological disasters on routine immunisation and vaccine-preventable disease (VPD) outbreaks among children and adolescents under 18 years. We searched Medline, Embase, Global Health, Scopus, and Web of Science for original studies and systematic reviews on the topic published by the 21st of October 2024. We included studies that quantitatively analysed the effect of any of the thirty Emergency Events Database (EM-DAT) recognised hydro-meteorological and geological disasters (or those fitting EM-DAT criteria) on a comprehensive list of World Health Organization (WHO)-recommended vaccines and the 23 diseases against which they prevent. We included 26 studies, of which 19 concerned with vaccine-preventable disease outbreaks and seven focused on routine immunisation disruption.. Our review indicates that floods, cyclones, droughts, extreme temperatures, tsunamis, and earthquakes may result in vaccine-preventable disease outbreaks and routine immunisation disruption, and identified young children and refugees as at-risk populations. Flooding was reported to be associated with water-borne and vector-borne vaccine-preventable disease outbreaks such as malaria. Poor water, sanitation and hygiene (WASH) were further recognised as facilitating conditions for vaccine-preventable disease outbreaks after disasters. The vaccination studies reported reduction in routine immunisation rates in the months following a disaster, considering infrastructural damage to health facilities and vaccine storage issues as common causes. Finally, there was significant knowledge gap on the effects of specific disasters (e.g., wildfires and volcanic eruptions) and diseases (e.g., influenza, yellow fever, malaria, and dengue).In conclusion, our review reinforce the need for better policies to ensure vaccine equity, resilient health system and safe WASH to prevent vaccine-preventable disease (VPD) outbreaks following hydro-meteorological and geological disasters.

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BackgroundFlooding from natural disasters has become increasingly common worldwide, increasing the risk of infectious disease transmission, particularly waterborne and vector-borne infections. Although many studies report outbreaks following floods, the evidence remains fragmented across regions and pathogens. A comprehensive review is needed to clarify these associations and inform effective prevention and response strategies.MethodsA systematic search of PubMed, Embase, and the Cochrane Library was conducted between November 2024 and January 2025, identifying studies published from January 1, 2014, to December 31, 2024. Eligible studies assessed the association between flooding and waterborne or vector-borne infections and their health outcomes or evaluated related prevention and response interventions. Data were synthesized narratively due to study heterogeneity.ResultsOf the 1,785 records identified, 71 studies met the inclusion criteria. Flooding was consistently associated with increased incidence of waterborne infections, including leptospirosis, cholera, bacillary dysentery, and hepatitis A/E, as well as vector-borne infections such as dengue and malaria. Outbreaks varied by region, flood characteristics, and the strength of existing public health infrastructure. The lag period between the onset of flooding and disease emergence ranged from days to weeks. Timely interventions such as chemoprophylaxis, vaccination, water, sanitation, and hygiene (WASH) measures, and vector control may help mitigate outbreaks; however, most included studies were observational in design, and the overall certainty of evidence was low to moderate. Data on health system impacts, including hospitalization rates, intensive care unit burden, and mortality stratified by level of care, remain limited.ConclusionFlooding was most frequently associated with increased incidence of cholera, bacillary dysentery, leptospirosis, dengue, and malaria, each with distinct lag periods critical for outbreak prediction. Reported lag periods ranged from days to weeks. Limited observational evidence suggests that doxycycline chemoprophylaxis for leptospirosis, oral cholera vaccination, and early vector control may be useful in selected post-flood settings. These findings support strengthened post-flood surveillance and context-specific preparedness measures, while highlighting the need for higher-quality comparative studies.RegistrationPROSPERO CRD42025635687.Clinical trial numbeNot applicable.

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