Conjugal transfer vaccinia

Is monkeypox a new, emerging sexually transmitted disease? A rapid review of the literature

Monkeypox, a milder disease compared to smallpox, is caused by a virus initially discovered and described in 1958 by the prominent Danish virologist von Magnus, who was investigating an infectious outbreak affecting monkey colonies. Currently, officially starting from May 2022, an outbreak of monkeypox is ongoing, with 51 000 cases being notified as of September 1, 2022-51 408 confirmed, 28 suspected, and 12 fatalities, for a grand total of 51 448 cases. More than 100 countries and territories are affected, from all the six World Health Organization regions. There are some striking features, that make this outbreak rather unusual when compared with previous outbreaks, including a shift on average age and the most affected age group, affected sex/gender, risk factors, clinical course, presentation, and the transmission route. Initially predominantly zoonotic, with an animal-to-human transmission, throughout the last decades, human-to-human transmission has become more and more sustained and effective. In particular, clusters of monkeypox have been described among men having sex with men, some of which have been epidemiologically linked to international travel to nonendemic countries and participation in mass gathering events/festivals, like the "Maspalomas (Gran Canaria) 2022 pride." This review will specifically focus on the "emerging" transmission route of the monkeypox virus, that is to say, the sexual transmission route, which, although not confirmed yet, seems highly likely in the diffusion of the infectious agent.

Contact transmission of vaccinia virus from smallpox vaccinees in the United States, 2003-2011

Since 2002, approximately 40,000 US civilians and 2.1 million military personnel have been vaccinated against smallpox. The vaccine contains live vaccinia virus that can be transferred through physical contact. This report summarizes numbers, rates, and characteristics of contact vaccinia cases that presented between December 2002 and March 2011. Cases were identified from reports in adverse event reporting systems and peer-reviewed literature. One hundred fifteen cases of vaccinia transmission through contact were identified (5.4 per 100,000 vaccinees); 52 reports (45%) noted laboratory confirmation. Three-quarters of vaccinees, but fewer than 8% of contact vaccinia cases, were described as military members. Most cases were household or intimate contacts (n=86, 75%) or wrestling partners (n=18, 16%) of vaccinees. Nearly all cases manifested mild, local skin reactions; of 14 hospitalized cases, one was life-threatening. Vaccinia transmission from vaccinees is relatively infrequent. Continued attention to both vaccinee education and screening for contraindications to vaccination is appropriate.

Vaccinia virus infections in martial arts gym, Maryland, USA, 2008

Vaccinia virus is an orthopoxvirus used in the live vaccine against smallpox. Vaccinia virus infections can be transmissible and can cause severe complications in those with weakened immune systems. We report on a cluster of 4 cases of vaccinia virus infection in Maryland, USA, likely acquired at a martial arts gym.

Coadministration of cidofovir and smallpox vaccine reduced vaccination side effects but interfered with vaccine-elicited immune responses and immunity to monkeypox

While the smallpox vaccine, Dryvax or Dryvax-derived ACAM2000, holds potential for public immunization against the spread of smallpox by bioterror, there is serious concern about Dryvax-mediated side effects. Here, we report that a single-dose vaccination regimen comprised of Dryvax and an antiviral agent, cidofovir, could reduce vaccinia viral loads after vaccination and significantly control Dryvax vaccination side effects. However, coadministration of cidofovir and Dryvax also reduced vaccine-elicited immune responses of antibody and T effector cells despite the fact that the reduced priming could be boosted as a recall response after monkeypox virus challenge. Evaluations of four different aspects of vaccine efficacy showed that coadministration of cidofovir and Dryvax compromised the Dryvax-induced immunity against monkeypox, although the covaccinated monkeys exhibited measurable protection against monkeypox compared to that of naïve controls. Thus, the single-dose coadministration of cidofovir and Dryvax effectively controlled vaccination side effects but significantly compromised vaccine-elicited immune responses and vaccine-induced immunity to monkeypox.