In view of serious and growing outbreak of monkeypox (Mpox) disease in the Democratic Republic of the Congo (DRC) that has now spread outside the country and detection of the new strain that first emerged in September 2023 outside DRC, WHO has invited manufacturers of mpox vaccines to submit an Expression of Interest for Emergency Use Listing (EUL) including data to prove that the vaccines are safe, effective, of assured quality and suitable for the target populations.
The EUL procedure is an emergency use authorization process, specifically developed to expedite the availability of unlicensed medical products like vaccines that are needed in public health emergency situations. EUL approval will improve vaccine availability particularly for resource constrained settings which have not yet issued their own national regulatory approval. The EUL also enables partners including Gavi and UNICEF to procure vaccines for distribution.
Monkeypox virus (MPXV) is a double-stranded DNA virus belonging to genus Orthopoxvirus along with vaccinia virus (VACV) and variola virus (VARV). It is closely related to smallpox, the deadliest virus in history responsible for unparalleled devastation of human population in the past centuries. With the complete eradication and subsequent cessation of smallpox vaccination programme (which had provided some cross protection against monkeypox virus as well), the current human population has much reduced levels of immunity against this group of viruses. This reasonably explains the current rise and spread of monkeypox virus from its endemic regions in Africa.
Mpox is a viral illness caused by the monkeypox virus. Mpox can be transmitted to humans through physical contact with infected persons, or with contaminated materials, or with infected animals.
Mpox vaccines currently in use:
For healthy adults, non-replicating (MVA-BN), minimally replicating (LC 16) or replicating vaccinia-based vaccines (ACAM2000) are appropriate.
MVA-BN is a 3rd generation mpox vaccine administered as two-dose subcutaneous injection given at least 4 weeks apart. Both 1 and 2 doses of MVA-BN are highly effective at preventing mpox.
LC16 and ACAM2000 are single dose mpox vaccine.
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References:
- WHO Press release – WHO invites mpox vaccine manufacturers to submit dossiers for emergency evaluation. Published 09 August 2024. Available at https://www.who.int/news/item/09-08-2024-who-invites-mpox-vaccine-manufacturers-to-submit-dossiers-for-emergency-evaluations
- WHO. Vaccines and immunization for monkeypox: Interim guidance, 16 November 2022. Available at https://iris.who.int/bitstream/handle/10665/364527/WHO-MPX-Immunization-2022.3-eng.pdf
- Pischel L., et al 2024. Vaccine effectiveness of 3rd generation mpox vaccines against mpox and disease severity: A systematic review and meta-analysis. Vaccine. Available online 21 June 2024. DOI: https://doi.org/10.1016/j.vaccine.2024.06.021
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Will Monkeypox go Corona way? (23 June 2022)
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