Dear Editor
The tell-tale of vaccination, from its inception to the present day, is marked by legions of groundbreaking achievements. This article sheds light on the direct, indirect, and population-level benefits of the modified vaccinia Ankara-Bavarian Nordic (MVA-BN) vaccine administered to prevent monkey pox infection as a study of efficiency and effectiveness. A reduction of 58% in laboratory-confirmed cases among vaccinated individuals provides significant relief amid the panic surrounding the disease. This study in Ontario highlights the MVA-BN vaccine and its contribution to herd immunity. Regional vaccination likely contributed to reduced mpox transmission, indirectly benefiting both vaccinated and unvaccinated individuals.
Although, the author mentions the limitations of using real world data and inability to run a randomised controlled trial in the context of rapid implementation, vaccine hesitancy could be a potential villain posing to be a significant threat in the real-world scenario. The SARS COVID-19 pandemic has exacerbated a global vaccine hesitancy. UNICEF (2023) reported a fair share of confidence decline in vaccines in 52 out of 55 countries, with some national statistics dropping to 33%. Furthermore, the WHO (2023) stresses that disruptions to immunization programs have left millions unvaccinated, jeopardising herd immunity for diseases such as measles and yellow fever.
Insufficient vaccination weakens herd immunity, particularly in low-income and marginalized populations. Evidence-based education on vaccines must be implemented to address this hazard. Comprehensive strategies are needed to ensure equitable access to healthcare, rebuilding confidence in health systems amongst marginalized communities.
Several measures are being implemented for infection control and outbreak prevention. Early case identification, contact tracing, travel restrictions, event curbs, adequate quarantine period, provision of appropriate personal protective equipment for healthcare workers have contributed to standard guidelines whilst avoidance of stigmatizing messaging about monkeypox, and the development of effective vaccines and postexposure prophylaxis aided the interventional programmes (Lai et al., 2022).
A recent study by Gao et al. (2024) explored mpox vaccine hesitancy among men who have sex with men in six Chinese cities. They successfully developed a hesitancy scale for Mpox Vaccine to demonstrate a relationship between hesitancy and vaccination intention in this high-risk group. It emphasized the importance of tailored strategies to address perceived risks and misinformation to increase vaccine uptake in vulnerable populations.
Insights from such studies provides reinforcement for further research and development. The mention in the article of the study findings being a contributing factor in slowing down regional infection transmission even without being designed to evaluate indirect effect or herd immunity is a commendable work of high value to the field. Steps to increase vaccine acceptance among high-risk groups to address global vaccination gaps will eventually lead us closer to the ultimate goal of universal coverage of health care.
References
1. UNICEF, 2023. New data indicates declining confidence in childhood vaccines of up to 44 percentage points in some countries during the COVID-19 pandemic. UNICEF Press Release. Available at: https://www.unicef.org/press-releases/new-data-indicates-declining-confi…
2. WHO, 2023. Immunization coverage. World Health Organization Fact Sheet. Available at: https://www.who.int/news-room/fact-sheets/detail/immunization-coverage
3. Lai, C.-C., Hsu, C.-K., Yen, M.-Y., Lee, P.-I., Ko, W.-C. and Hsueh, P.-R., 2022. Monkeypox: An emerging global threat during the COVID-19 pandemic. Journal of Microbiology, Immunology and Infection, 55(5), pp.787–794. Available at: https://doi.org/10.1016/j.jmii.2022.08.011
4. Gao, Y., Liu, S., Xu, H., Wang, Y., Xu, G., Hu, F., Zhang, J. and Cai, Y., 2024. The Mpox Vaccine Hesitancy Scale for Mpox: Links with Vaccination Intention among Men Who Have Sex with Men in Six Cities of China. Vaccines, 12(9), p.1009. Available at: https://doi.org/10.3390/vaccines12091009
5. Poland, G.A., Kennedy, R.B. and Tosh, P.K., 2022. Prevention of monkeypox with vaccines: A rapid review. The Lancet Infectious Diseases, 22, pp.e349–e358. Available at: https://doi.org/10.1016/S1473-3099(22)00574-6
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