BACKGROUND Mpox was first identified in the Democratic Republic of the Congo (DRC) in 1970. In 2023, a historic outbreak of mpox occurred in the country, continuing into 2024. Over 14 000 cases and 600 deaths were reported in 2023 alone, representing a major increase from previous outbreaks. The modified vaccinia Ankara vaccine (brand names JYNNEOS, Imvamune, and Imvanex) was used in the 2022 mpox outbreak in the USA and Europe. However, at the time of the study, vaccination had not been made available in the DRC. We aimed to inform policy and decision makers on the potential benefits of, and resources needed, for mpox vaccination campaigns in the DRC by providing counterfactual scenarios evaluating the short-term effects of various vaccination strategies on mpox cases and deaths, if such a vaccination campaign had been undertaken before the 2023-24 outbreak. METHODS A dynamic transmission model was used to simulate mpox transmission in the DRC, stratified by age (<5, 5-15, and >15 years) and province. The model was used to simulate potential vaccination strategies, varying by age and region (endemic provinces, non-endemic provinces with historic cases, and all provinces) assessing the effect the strategies would have on deaths and cases in an epidemic year similar to 2023. In addition, we estimated the number of vaccine doses needed to implement each strategy. FINDINGS Without vaccination, our model predicted 14 700 cases and 700 deaths from mpox over 365 days. Vaccinating 80% of all children younger than 5 years in endemic regions led to a 27% overall reduction in cases and a 43% reduction in deaths, requiring 10·5 million vaccine doses. Vaccinating 80% of all children younger than 5 years in all regions led to a 29% reduction in cases and a 43% reduction in deaths, requiring 33·1 million doses. Vaccinating 80% of children aged 15 years or younger in endemic provinces led to a 54% reduction in cases and a 71% reduction in deaths, requiring 26·6 million doses. INTERPRETATION When resources are limited, vaccinating children aged 15 years or younger, or younger than 5 years, in endemic regions of the DRC would be the most efficient use of vaccines. Further research is needed to explore long-term effects of a one-time or recurrent vaccination campaign. FUNDING Canadian Institutes of Health Research, Canadian International Development Research Centre, US Department of Defense (Defense Threat Reduction Agency, Mpox Threat Reduction Network), Global Affairs Canada (Weapons Threat Reduction Program), US Department for Agriculture (Agriculture Research Service, Non-Assistance Cooperative Agreement).

中文翻译：

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模拟刚果民主共和国控制和缓解 mpox 的疫苗接种方法。


背景 猴痘于 1970 年在刚果民主共和国 （DRC） 首次被发现。2023 年，该国发生了历史性的猴痘疫情，并持续到 2024 年。仅在 2023 年，就报告了超过 14000 例病例和 600 例死亡，比以前的疫情大幅增加。改良的安卡拉牛痘疫苗（商品名 JYNNEOS、Imvamune 和 Imvanex）用于 2022 年美国和欧洲的猴痘疫情。然而，在研究进行时，DRC 尚未提供疫苗接种。我们旨在通过提供反事实情景来评估各种疫苗接种策略对 mpox 病例和死亡的短期影响，让政策和决策者了解刚果民主共和国 mpox 疫苗接种活动的潜在益处和所需资源（如果在 2023-24 年疫情爆发之前进行了此类疫苗接种活动）。方法 采用动态传播模型模拟刚果民主共和国 mpox 传播，按年龄 （<5、5-15 和 >15 岁） 和省份分层。该模型用于模拟潜在的疫苗接种策略，因年龄和地区（流行省份、有历史病例的非流行省份和所有省份）而异，评估这些策略在类似于 2023 年的流行年份对死亡和病例的影响。此外，我们估计了实施每种策略所需的疫苗剂量数。发现在没有接种疫苗的情况下，我们的模型预测了 365 天内 14 700 例 mpox 病例和 700 例死亡。在流行地区为 80% 的 5 岁以下儿童接种疫苗，导致病例总数减少 27%，死亡人数减少 43%，需要 10·500 万剂疫苗。 在所有地区为 80% 的 5 岁以下儿童接种疫苗导致病例减少 29%，死亡人数减少 43%，需要 33·100 万剂。在流行省份为 80% 的 15 岁或以下儿童接种疫苗导致病例减少 54%，死亡人数减少 71%，需要 26·600 万剂。解释 当资源有限时，在 DRC 流行地区为 15 岁或以下或 5 岁以下的儿童接种疫苗将是最有效的疫苗使用方式。需要进一步的研究来探索一次性或重复疫苗接种运动的长期影响。资助 加拿大卫生研究院、加拿大国际发展研究中心、美国国防部（国防威胁减少局、猴痘威胁减少网络）、加拿大全球事务部（减少武器威胁计划）、美国农业部（农业研究服务、非援助合作协议）。