MVA-BN vaccine effectiveness: A systematic review of real-world evidence in outbreak settings

• Published in: Vaccine Vol. 42; no. 26; p. 126409
• Main Authors: Mason, Lauren M.K., Betancur, Estefania, Riera-Montes, Margarita, Lienert, Florian, Scheele, Suzanne
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 02.12.2024; Elsevier Limited
• Subjects: Allergy and Immunology; At risk populations; Bibliographic literature; Clinical trials; Data collection; Democratic Republic of the Congo; Democratic Republic of the Congo - epidemiology; Disease control; Disease Outbreaks - prevention & control; Effectiveness; Epidemics; Estimates; Heterogeneity; HIV; Human immunodeficiency virus; Humans; Immune system; Immunization; Infections; Literature reviews; Medical research; Medical Subject Headings-MeSH; Meta-analysis; Monkeypox virus; Mpox; Mpox (monkeypox) - prevention & control; Observational studies; Outbreaks; Population studies; Populations; Post-exposure prophylactic vaccination; Pre-exposure prophylactic vaccination; Public health; Quality assessment; Quality control; Ratios; risk; Sexually transmitted diseases; Sexually transmitted infection; Smallpox; Smallpox - epidemiology; Smallpox - immunology; Smallpox - prevention & control; Smallpox Vaccine - administration & dosage; Smallpox Vaccine - immunology; STD; Subject heading schemes; Systematic review; vaccination; Vaccination - methods; Vaccine Efficacy; Vaccines; Vaccinia; Vaccinia - epidemiology; Vaccinia - immunology; Vaccinia - prevention & control; Viral diseases; Viruses; Western Africa; Democratic Republic of the Congo; Ankara Turkey; Turkey; Congo-Democratic Republic of Congo; United States > US; Western Africa; Mpox; Sexually transmitted infection; Immunization; Monkeypox virus; Pre-exposure prophylactic vaccination; Post-exposure prophylactic vaccination
• ISSN: 0264-410X; 1873-2518; 1873-2518
• DOI: 10.1016/j.vaccine.2024.126409

Background: Mpox is a disease endemic to Central and West Africa. It caused outbreaks in non-endemic countries, mainly in 2022. The endemic Democratic Republic of Congo is currently experiencing its largest outbreak yet. The vaccine Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN) is approved for active immunization against mpox and smallpox. Since the outbreak in 2022, real-world studies have assessed MVA-BN's vaccine effectiveness (VE) against mpox, and this systematic literature review aims to summarize the most current evidence. Methods: Medline (via PubMed), Embase, and LILACS were searched, as well as grey literature sources and publications' bibliographies to identify observational studies published between 1/Jan/2022 and 28/Feb/2024 that estimate the VE of MVA-BN against mpox or provide risk measures that allow calculation of these VE estimates. Data were presented descriptively in tables and text; the methodological quality of included records was assessed using NHLBI/NIH quality assessment tools. Results: The literature search identified 16 records that fit the inclusion criteria. The studies took place in high-income countries and were heterogeneous in design, setting, and definition of at-risk populations. MVA-BN VE estimates against mpox infection were assessed. Where the study population was exclusively or primarily those receiving pre-exposure prophylactic vaccination, the adjusted VE estimates ranged from 35 % to 86 % (n = 8 studies) for one dose and from 66 % to 90 % (n = 5) for two doses. Where only post-exposure prophylactic vaccination was assessed, adjusted VE estimates were reported for one dose only at 78 % and 89 % (n = 2). Additionally, MVA-BN reduced the risk of mpox-related hospitalization in one study and the severity of mpox clinical manifestations in two studies. Conclusions: Despite heterogeneity in study design, setting, and at-risk populations, the reported VE estimates against mpox infection demonstrated the effectiveness of one or two doses of MVA-BN in the context of an outbreak across multiple countries. •We reviewed real-world evidence on the vaccine effectiveness of MVA-BN against mpox•Eligible studies were heterogeneous in design, setting, and at-risk populations•MVA-BN vaccination reduced the risk of mpox infections and hospitalization•MVA-BN vaccination reduced the severity of mpox clinical manifestations•Real-world evidence supports the use of MVA-BN for mpox outbreak control