Anthrax vaccine suspension for injection 0.5ml ampoules

Post-exposure prophylaxis may be recommended during chemical, biological, radiological or nuclear (CBRN) emergencies and must often be initiated rapidly to be effective. Understanding factors that affect uptake (initiation) and subsequent adherence (completion) will help to minimise barriers and support adherence during emergencies. This systematic review synthesises evidence on factors associated with uptake of and adherence to prophylaxis following exposure to anthrax, radiation, smallpox, or viral pandemic diseases such as influenza or COVID-19. The review was pre-registered (https://osf.io/f5nmw). We searched Medline, Embase, APA PsycINFO, Web of Science, Scopus, the Cochrane Library, and subject specific databases, with no language or date restrictions. PRISMA and synthesis without meta-analysis (SWiM) guidelines were followed alongside NICE recommendations for risk of bias assessment. Data were extracted on factors associated with, and interventions targeting, uptake and adherence to prophylaxis across the four scenarios. Of 17,217 records screened, 21 studies were included. Uptake and adherence varied widely. Evidence on associated factors was inconsistent and generally of low certainty. Few scenario-specific differences were identified; variation was more strongly associated with population and contextual factors. Common barriers included concerns about side effects, low perceived risk, and lack of trust in information sources. Evidence on the effectiveness of interventions was limited to two studies, at high risk of bias. In conclusion, preparedness should prioritise addressing shared motivational and practical barriers across settings. There is a critical need to develop and evaluate interventions to support timely uptake and adherence to prophylaxis before emergencies occur.

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BackgroundAnthrax remains a persistent public health, veterinary, and ecological challenge in Africa, sustained by fragmented surveillance systems characterized by underreporting, limited diagnostic capacity, and weak cross-sectoral coordination. The absence of integrated surveillance across human, livestock, wildlife, and environmental interfaces constrains accurate burden estimation and timely outbreak response.MethodsWe conducted a systematic review and meta-analysis following PRISMA guidelines to synthesize available evidence on anthrax epidemiology in Africa. Studies published between January 2000 and February 2025 were identified from PubMed and Web of Science. Observational studies reporting primary epidemiological data in humans, livestock, wildlife, or environmental samples were eligible. Quantitative synthesis was restricted to cross-sectional studies reporting extractable prevalence data. Pooled estimates were generated using a logit-transformed random-effects model (REML), with heterogeneity assessed using I 2 and τ2 statistics. Studies not meeting meta-analytic criteria were synthesized narratively within a One Health framework.ResultsTen cross-sectional studies comprising 19,955 samples and 2,079 confirmed anthrax cases were included in the meta-analysis. The crude aggregated prevalence was 9.88% (95% CI: 9.46%-10.30%). The pooled prevalence from the logit-transformed random-effects model was 20% (95% CI: 8%-44%). Substantial heterogeneity was observed (I 2 = 98.2%), indicating marked epidemiological variability across ecological settings, host populations, and surveillance systems. Narrative synthesis further highlighted wildlife outbreaks and environmental persistence of Bacillus anthracis, though such studies remain comparatively scarce.ConclusionThe available evidence on anthrax in Africa is limited, geographically uneven, and highly heterogeneous. The pooled estimate should therefore be interpreted as a summary measure of reported prevalence rather than a precise continental burden estimate. These findings underscore persistent transmission within fragmented surveillance systems and support strengthened One Health-based approaches integrating human, animal, wildlife, and environmental health sectors to improve surveillance, early detection, and coordinated response across Africa.

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BackgroundInfectious Medical Waste (IMW) from both human and animal healthcare sources have the potential to transmit diseases in human populations due to its pathogenic composition. Conversely, a paucity of data regarding cause-and-effect relationships inhibits our understanding of the extent to which disease transmission occurs. In parts of Africa where the management of IMW is not prioritized, the risks to public health, along with its global implications cannot be ignored.MethodologyA systematic literature search following the PRISMA guidelines was conducted across five electronic databases including PubMed, Embase, Scopus, ProQuest and Ovid. Relevant studies were identified using keywords such as 'infectious medical waste', 'infectious diseases', 'routes of infection', 'route of transmission', 'epidemics', 'diseases', 'sub-Sahara Africa', and 'infectious waste management'.ResultsOverall, 6721 articles were retrieved from the search, 6634 of which were excluded due to a lack of alignment with the study objectives. After screening, 87 studies were deemed eligible and were included in the review. Our findings identified 11 diseases that are potentially transmissible via IMW. These include Anthrax, Crimean-congo haemorrhagic Fever, Ebola Virus Disease, Hepatitis B, Hepatitis C, Human Immunodeficiency Virus, Lassa Fever, Measles, Monkeypox, Plague, and Rift Valley Fever. Disease transmission may occur via human contact with different classes of IMW, contaminated materials and accessories.ConclusionsMedical waste can be a source of infectious disease transmission. However, evidence of such a pathway is currently unavailable due to a paucity of scientific data. Therefore, further research is needed to establish cause-and-effect relationships.

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BackgroundThis double-blinded randomized Phase 3 study evaluated the immunogenicity and safety of CYFENDUS® vaccine (AV7909; Anthrax Vaccine Adsorbed, Adjuvanted) to support licensure for post-exposure prophylaxis following suspected or confirmed Bacillus anthracis exposure when administered with the recommended antibacterial drugs.MethodsHealthy adult participants (n = 3689) aged 18 to 65 were randomized to receive CYFENDUS vaccination (intramuscularly at 0, 2 weeks) or BioThrax® (Anthrax Vaccine Absorbed) [subcutaneously at 0, 2, 4 weeks]. Immunogenicity at Day 64 (seven weeks after the last CYFENDUS vaccine dose; five weeks after the last BioThrax vaccine dose) was evaluated using a 50 % neutralizing factor (NF50) threshold of protective immunogenicity generated by a toxin neutralizing antibody (TNA) assay, and by evaluating non-inferiority of CYFENDUS to BioThrax vaccination. Safety was assessed by physical exams, vital signs, solicited local injection site and systemic reactogenicity, and unsolicited adverse events (AEs).ResultsThe prospectively defined success criteria were met for the primary immunogenicity endpoints. The lower bound of the two-sided 95 % confidence interval (CI) for the proportion of CYFENDUS participants with TNA NF50 ≥ 0.56 was above the pre-defined criterion of ≥40 % (95 % CI: 64.5 %, 68.1 %). The lower bound of the two-sided 95 % CI of the difference in the proportion of participants with TNA NF50 ≥ 0.29 in the CYFENDUS versus the BioThrax vaccine group was greater than the pre-defined non-inferiority criterion of -15 % as well as demonstrating statistical superiority (95 % CI: 20.0, 29.2 %), a closed hypothesis test supported by regulatory agencies in well-controlled clinical trials. The most common adverse events (AE) were injection site-related; most reported solicited reactogenicities and AEs were either Grade 1 or 2 severity.ConclusionsThe study met the pre-defined endpoint criteria, demonstrating protective level of immune response and non-inferiority of CYFENDUS to BioThrax vaccination. The CYFENDUS vaccine was well-tolerated in healthy adults.Trial registrationClinicalTrials.gov Identifier: NCT03877926.

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