Effectiveness of one dose of MVA-BN smallpox vaccine against mpox in England using the case-coverage method: an observational study.

The UK experienced a national outbreak of mpox (formerly known as monkeypox) disease that started in May, 2022, as did many other countries worldwide, with case numbers rising rapidly, mainly among gay, bisexual, and other men who have sex with men (GBMSM). To control the outbreak, Modified Vaccinia Ankara-Bavaria Nordic (MVA-BN), an attenuated smallpox vaccine, was offered to at-risk GBMSM. We aimed to assess the effectiveness of a single MVA-BN dose against symptomatic mpox disease in at-risk GBMSM. In this case-coverage study, mpox cases in England were sent questionnaires collecting information on demographics, vaccination history, symptoms, and sexual orientation. Returned questionnaires were linked to laboratory data and a public health case management system (HP Zone) to obtain additional information on symptom onset and specimen date. Cases with a rash onset date (or alternative proxy) between July 4 and Oct 9, 2022, were included. Females, heterosexual men, and those with missing vaccination information were excluded. Vaccine effectiveness was calculated using the case-coverage method in which vaccine coverage among cases is compared with coverage in the eligible population, estimated from doses given to GBMSM and the estimated size of at-risk GBMSM. Sensitivity analyses included an increase and decrease of 20% differences in the estimated high-risk GBMSM population size. By Nov 3, 2022, 1102 people had responded to questionnaires, of which 739 were excluded (52 females or self-declared male heterosexuals, 590 with an index date outside of the study period, and 97 missing a vaccination date). 363 cases were included in the analyses. Vaccine uptake among eligible GBMSM increased steadily from July, 2022, reaching 47% by Oct 9, 2022. Of the 363 confirmed cases, eight cases either did occur or were likely to have occurred at least 14 days after vaccination, 32 within 0-13 days after vaccination, and the rest were unvaccinated. The estimated vaccine effectiveness against symptomatic mpox at least 14 days after a single dose was 78% (95% CI 54 to 89) ranging from 71 to 85 in sensitivity analyses. Vaccine effectiveness within 0-13 days after vaccination was -4% (95% CI -50 to 29). A single MVA-BN dose was highly protective against symptomatic mpox disease among at-risk GBMSM, making it a useful tool for mpox outbreak control when rapid protection is needed. For cases in which numbers at highest risk of infection exceed vaccine supply, there might be benefit in prioritising delivery of first doses. UK Health Security Agency.

Bertran M ，Andrews N ，Davison C ，Dugbazah B ，Boateng J ，Lunt R ，Hardstaff J ，Green M ，Blomquist P ，Turner C ，Mohammed H ，Cordery R ，Mandal S ，Campbell C ，Ladhani SN ，Ramsay M ，Amirthalingam G ，Bernal JL ... -  《-》

Early evaluation of the safety, reactogenicity, and immune response after a single dose of modified vaccinia Ankara-Bavaria Nordic vaccine against mpox in children: a national outbreak response.

In response to a national mpox (formerly known as monkeypox) outbreak in England, children exposed to a confirmed mpox case were offered modified vaccinia Ankara-Bavaria Nordic (MVA-BN), a third-generation smallpox vaccine, for post-exposure prophylaxis. We aimed to assess the safety and reactogenicity and humoral and cellular immune response, following the first reported use of MVA-BN in children. This is an assessment of children receiving MVA-BN for post-exposure prophylaxis in response to a national mpox outbreak in England. All children receiving MVA-BN were asked to complete a post-vaccination questionnaire online and provide a blood sample 1 month and 3 months after vaccination. Outcome measures for the questionnaire included reactogenicity and adverse events after vaccination. Blood samples were tested for humoural, cellular, and cytokine responses and compared with unvaccinated paediatric controls who had never been exposed to mpox. Between June 1 and Nov 30, 2022, 87 children had one MVA-BN dose and none developed any serious adverse events or developed mpox disease after vaccination. Post-vaccination reactogenicity questionnaires were completed by 45 (52%) of 87 children. Their median age was 5 years (IQR 5-9), 25 (56%) of 45 were male, and 22 (49%) of 45 were White. 16 (36%) reported no symptoms, 18 (40%) reported local reaction only, and 11 (24%) reported systemic symptoms with or without local reactions. Seven (8%) of 87 children provided a first blood sample a median of 6 weeks (IQR 6·0-6·5) after vaccination and five (6%) provided a second blood sample at a median of 15 weeks (14-15). All children had poxvirus IgG antibodies with titres well above the assay cutoff of OD450nm 0·1926 with mean absorbances of 1·380 at six weeks and 0·9826 at 15 weeks post-vaccination. Assessment of reactivity to 27 recombinant vaccina virus and monkeypox virus proteins showed humoral antigen recognition, primarily to monkeypox virus antigens B6, B2, and vaccina virus antigen B5, with waning of humoral responses observed between the two timepoints. All children had a robust T-cell response to whole modified vaccinia Ankara virus and a select pool of conserved pan-Poxviridae peptides. A balanced CD4+ and CD8+ T-cell response was evident at 6 weeks, which was retained at 15 weeks after vaccination. A single dose of MVA-BN for post-exposure prophylaxis was well-tolerated in children and induced robust antibody and cellular immune responses up to 15 weeks after vaccination. Larger studies are needed to fully assess the safety, immunogenicity, and effectiveness of MVA-BN in children. Our findings, however, support its on-going use to prevent mpox in children as part of an emergency public health response. UK Health Security Agency.

Ladhani SN ，Dowell AC ，Jones S ，Hicks B ，Rowe C ，Begum J ，Wailblinger D ，Wright J ，Owens S ，Pickering A ，Shilltoe B ，McMaster P ，Whittaker E ，Zuo J ，Powell A ，Amirthalingam G ，Mandal S ，Lopez-Bernal J ，Ramsay ME ，Kissane N ，Bell M ，Watson H ，Ho D ，Hallis B ，Otter A ，Moss P ，Cohen J ... -  《-》

Effectiveness of Modified Vaccinia Ankara-Bavaria Nordic Vaccination in a Population at High Risk of Mpox: A Spanish Cohort Study.

With more than 7500 cases reported since April 2022, Spain has experienced the highest incidence of mpox in Europe. From 12 July onward, the modified vaccinia Ankara-Bavaria Nordic (MVA-BN) smallpox vaccine was offered as pre-exposure prophylaxis for those receiving pre-exposure prophylaxis for human immunodeficiency virus (HIV-PrEP). Our aim was to assess the effectiveness of 1 dose of MVA-BN vaccine as pre-exposure prophylaxis against mpox virus (MPXV) infection in persons on HIV-PrEP. National retrospective cohort study between 12 July and 12 December 2022. Individuals aged ≥18 years receiving HIV-PrEP as of 12 July with no previous MPXV infection or vaccination were eligible. Each day, we matched individuals receiving a first dose of vaccine and unvaccinated controls of the same age and region. We used a Kaplan-Meier estimator, calculated risk ratios (RR) and vaccine effectiveness (VE = [1 - RR]x100). We included 5660 matched pairs, with a median follow-up of 62 days (interquartile range, 24-97). Mpox cumulative incidence was 5.6 per 1000 (25 cases) in unvaccinated and 3.5 per 1000 (18 cases) in vaccinated. No effect was found during days 0-6 post-vaccination (VE, -38.3; 95% confidence interval [CI], -332.7 to 46.4), but VE was 65% at ≥7 days (95% CI, 22.9 to 88.0) and 79% at ≥14 days (95% CI, 33.3 to 100.0) post-vaccination. One dose of MVA-BN vaccine offered protection against mpox in most-at-risk population shortly after the vaccination. Further studies need to assess the VE of a second dose and the duration of protection over time.

Fontán-Vela M ，Hernando V ，Olmedo C ，Coma E ，Martínez M ，Moreno-Perez D ，Lorusso N ，Vázquez Torres M ，Barbas Del Buey JF ，Roig-Sena J ，Pastor E ，Galmés Truyols A ，Artigues Serra F ，Sancho Martínez RM ，Latasa Zamalloa P ，Pérez Martínez O ，Vázquez Estepa A ，García Rojas AJ ，Barreno Estévez AI ，Sánchez-Migallón Naranjo A ，Pérez Martín JJ ，Peces Jiménez P ，Morales Romero R ，Castilla J ，García Cenoz M ，Huerta Huerta M ，Boone ALD ，Macías Ortiz MJ ，Álvarez Río V ，Rodríguez Recio MJ ，Merino Díaz M ，Berradre Sáenz B ，Villegas-Moreno MT ，Limia A ，Diaz A ，Monge S ，Spanish MPOX Vaccine Effectiveness Study Group ... -  《-》

Transmission dynamics and effect of control measures on the 2022 outbreak of mpox among gay, bisexual, and other men who have sex with men in England: a mathematical modelling study.

Zhang XS ，Mandal S ，Mohammed H ，Turner C ，Florence I ，Walker J ，Niyomsri S ，Amirthalingam G ，Ramsay M ，Charlett A ，Vickerman P ... -  《-》

A survey-based assessment of rates and covariates of mpox diagnosis and vaccination provides evidence to refine eligibility criteria for mpox vaccination among gay, bisexual and other men who have sex with men in the Netherlands.

The 2022 multicountry mpox outbreaks predominantly affected gay, bisexual and other men who have sex with men (GBMSM) in non-endemic countries, including in the Netherlands. We conducted a survey-based assessment of the alignment between the risk factors associated with mpox diagnosis among GBMSM in the Netherlands and the eligibility criteria used in 2022 for vaccinating this group, with the aim to refine these criteria. An online self-report survey was conducted among adult GBMSM in the Netherlands between 29 July and 30 August 2022, corresponding to the first month of the Dutch mpox vaccination campaign. GBMSM were recruited via advertisements on social media and gay dating apps. Participants reported on their sexual behaviour, mpox diagnosis, and/or (initial) mpox vaccination since the start of the outbreak. Covariables of mpox diagnosis and vaccination were assessed using logistic regression analyses. Of the 2,460 participants, 73 (3.0%, 95% CI 2.3-3.6%) were diagnosed with mpox and 485 (19.7%, 95% CI 18.1-21.3%) had received (initial) mpox vaccination. Using sample weighting, we estimated that, of the GBMSM population aged 18-80 years in the Netherlands, 1.1% (95% CI 0.7-1.6%) had been diagnosed with mpox and 7.8% (95% CI 6.8-8.9%) had received (initial) vaccination. HIV-PrEP use, living with HIV, reporting ≥20 sex partners in the past 12 months, and sex in sex venues/parties in the past 2 months were independent risk factors for mpox diagnosis. Except for sex in sex venues/parties, these variables were also independently associated with mpox vaccination. This study provides novel evidence regarding the degree to which the 2022 eligibility criteria for mpox vaccination align with the risk factors for mpox among GBMSM in the Netherlands. The findings contribute to a refinement of the eligibility criteria for mpox vaccination, to which sex in sex venues/parties should be added.

Adam PCG ，Op de Coul ELM ，Zantkuijl P ，Xiridou M ，Bos H ，Blom C ，Ketsuwan I ，Te Wierik MJM ，David S ，de Wit JBF ... -  《Frontiers in Public Health》