MMWR Morb Mortal Wkly Rep. 2022 Oct 7;71(40):1278-1282. doi: 10.15585/mmwr.mm7140e3.
Human monkeypox is caused by Monkeypox virus (MPXV), an Orthopoxvirus, previously rare in the United States (1). The first U.S. case of monkeypox during the current outbreak was identified on May 17, 2022 (2). As of September 28, 2022, a total of 25,341 monkeypox cases have been reported in the United States.* The outbreak has disproportionately affected gay, bisexual, and other men who have sex with men (MSM) (3). JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic), administered subcutaneously as a 2-dose (0.5 mL per dose) series with doses administered 4 weeks apart, was approved by the Food and Drug Administration (FDA) in 2019 to prevent smallpox and monkeypox infection (4). U.S. distribution of JYNNEOS vaccine as postexposure prophylaxis (PEP) for persons with known exposures to MPXV began in May 2022. A U.S. national vaccination strategy for expanded PEP, announced on June 28, 2022, recommended subcutaneous vaccination of persons with known or presumed exposure to MPXV, broadening vaccination eligibility. FDA emergency use authorization (EUA) of intradermal administration of 0.1 mL of JYNNEOS on August 9, 2022, increased vaccine supply (5). As of September 28, 2022, most vaccine has been administered as PEP or expanded PEP. Because of the limited amount of time that has elapsed since administration of initial vaccine doses, as of September 28, 2022, relatively few persons in the current outbreak have completed the recommended 2-dose series. To examine the incidence of monkeypox among persons who were unvaccinated and those who had received ≥1 JYNNEOS vaccine dose, 5,402 reported monkeypox cases occurring among males aged 18-49 years during July 31-September 3, 2022, were analyzed by vaccination status across 32 U.S. jurisdictions.** Average monkeypox incidence (cases per 100,000) among unvaccinated persons was 14.3 (95% CI = 5.0-41.0) times that among persons who received 1 dose of JYNNEOS vaccine ≥14 days earlier. Monitoring monkeypox incidence by vaccination status in timely surveillance data might provide early indications of vaccine-related protection that can be confirmed through other well-controlled vaccine effectiveness studies. This early finding suggests that a single dose of JYNNEOS vaccine provides some protection against monkeypox infection. The degree and durability of such protection is unknown, and it is recommended that people who are eligible for monkeypox vaccination receive the complete 2-dose series.
人类猴痘是由猴痘病毒（MPXV）引起的，猴痘病毒是正痘病毒属的一种，以前在美国很少见（1）。美国首例猴痘病例于 2022 年 5 月 17 日确诊（2）。截至 2022 年 9 月 28 日，美国共报告了 25341 例猴痘病例*。该疫情主要影响男同性恋者、双性恋者和其他与男性发生性关系的男性（MSM）（3）。JYNNEOS 疫苗（改良安卡拉痘苗，巴伐利亚 Nordic）于 2019 年经美国食品和药物管理局（FDA）批准，可预防天花和猴痘感染，作为皮下 2 剂（每剂 0.5 毫升）系列，间隔 4 周接种（4）。美国于 2022 年 5 月开始向已知接触过猴痘病毒的人提供 JYNNEOS 疫苗作为接触后预防（PEP）。2022 年 6 月 28 日宣布的一项扩大 PEP 的美国全国疫苗接种策略建议对已知或推测接触过猴痘病毒的人进行皮下接种，扩大了接种资格（5）。2022 年 8 月 9 日，FDA 紧急使用授权（EUA）批准皮内注射 0.1 毫升 JYNNEOS，增加了疫苗供应（5）。截至 2022 年 9 月 28 日，大多数疫苗都作为 PEP 或扩大 PEP 进行了接种。由于从最初接种疫苗到现在的时间相对较短，截至 2022 年 9 月 28 日，当前疫情中相对较少的人完成了推荐的 2 剂系列接种（5）。为了研究未接种疫苗者和至少接种过 1 剂 JYNNEOS 疫苗者的猴痘发病率，分析了 2022 年 7 月 31 日至 9 月 3 日期间，年龄在 18-49 岁的男性中报告的 5402 例猴痘病例的疫苗接种情况，按 32 个美国司法管辖区的疫苗接种状况进行了分析**。未接种疫苗者的猴痘发病率（每 10 万人中的病例数）平均为接种 1 剂 JYNNEOS 疫苗且至少 14 天的人群的 14.3（95%CI=5.0-41.0）倍。及时监测疫苗接种状况的猴痘发病率可能会提供疫苗相关保护的早期迹象，这些迹象可以通过其他经过良好控制的疫苗有效性研究得到证实。这一早期发现表明，1 剂 JYNNEOS 疫苗可提供一定程度的猴痘感染预防。这种保护的程度和持久性尚不清楚，建议有资格接种猴痘疫苗的人完成完整的 2 剂系列接种。
