Antibody Titers against Mpox Virus after Vaccination

This letter from the NYC OSMI study reports immunogenicity outcomes following MVA-BN (JYNNEOS) mpox vaccination in 145 participants,24% with HIV infection, 89% identifying as LGBTQ+, and 20% previously vaccinated against smallpox. IgG titers against MPXV H3L protein peaked after two doses, with durability influenced by prior smallpox vaccination (antibody half-life: 291 days vs. 108 days). No differences in titers were observed between subcutaneous vs. intradermal administration or HIV status. In HIV-positive individuals, CD4+ count correlated positively with antibody titers (R² = 0.41). Findings suggest durable immune response post-vaccination regardless of route or HIV status, but highlight the need for future studies to assess booster necessity and long-term protection.

This letter from the NYC OSMI study reports immunogenicity outcomes following MVA-BN (JYNNEOS) mpox vaccination in 145 participants,24% with HIV infection, 89% identifying as LGBTQ+, and 20% previously vaccinated against smallpox. IgG titers against MPXV H3L protein peaked after two doses, with durability influenced by prior smallpox vaccination (antibody half-life: 291 days vs. 108 days). No differences in titers were observed between subcutaneous vs. intradermal administration or HIV status. In HIV-positive individuals, CD4+ count correlated positively with antibody titers (R² = 0.41). Findings suggest durable immune response post-vaccination regardless of route or HIV status, but highlight the need for future studies to assess booster necessity and long-term protection.