www.thelancet.com/infection Vol 24 , 2024 年 12 月 / 2024 年 9 月 18 日線上發表 https://doi.org/10.1016/ S1473-3099(24)00614-5
2024年8月13日，非洲疾病管制與預防中心宣布mpox為非洲大陸安全上的突發公共衛生事件。隔天，世衛組織宣布mpox為國際關注的突發公共衛生事件。自 2023 年以來，猴痘病毒 (MPXV) 第I 分支型的傳播大幅增加，大多數病例報告於剛果民主共和國。 2023 年報告死亡人數為738 人，截至2024 年8 月31 日死亡人數超過600 人，這段時期非洲聯盟的MPOX 死亡率已超過2022-23 年IIb 分支型爆發期間的全球死亡率，該次爆發流行主要影響同性戀、雙性戀和其他男性與男性發生性關係的人 (MSM)。新分支Ib 的出現強調了進一步研究的迫切需要，以了解導致該新分支的突變對MPXV 傳播動態和mpox 疾病嚴重程度的影響。在遏制 2022-23 年IIb 分支的爆發上，有幾個相關的因素：MPXV 感染後的自然免疫力、使用改良牛痘病毒之巴伐利亞北歐疫苗進行免疫、診斷測試的可用性以及行為改變。
在《刺胳針傳染病》中，Mateo Prochazka和同事提供了於2023 年 5 月 19 日至 5 月 31 日期間對 23 個國家被認定為男同性戀者、雙性戀男性、男男性行為者、跨性別者或非二元性別之參與者所進行的回顧性調查數據顯示，有50·9% 的參與者調整了其性行為以應對全球 MPXV clade IIb 疫情。這些行為適應包括減少性伴侶的數量 (93·2%)，以及在報告曾參與這些活動的人中，避免群體性行為 (88·4%)、性交易場所的性行為(84·6%) 和藥愛性行為( 53·6%)。有超過一半的參與者的這些變化持續了 4 個月或更長時間。如果未來mpox再次出現且傳播速度迅速增加，有79·8%的參與者表示願意調整自己的性行為。Prochazka 及其同事的研究結果，與先前針對不同地區 之MSM 的幾項研究結果一致。 作者的結論是，他們的研究支持這樣的假設：行為變化以及自然免疫力是2022 年底MSM 中MPXV clade IIb 傳播迅速下降的主要驅動因素。疫苗接種活動是在疫情達到高峰後才開始的，再加上疫苗接種率較低地區傳播率的下降，顯示疫苗接種本身不太可能成為控制疫情的主要因素。
這些數據對於在 MSM 中再次出現 MPOX 事件時為公共衛生政策提供至關重要之資訊，並強調了風險溝通和社區參與的重要性。在 2022-23 年全球 MPOX 爆發期間，我們吸取了有關性傳播感染背景下的風險溝通和社區參與的幾個重要經驗教訓。首先，針對特定群體改變性行為的指令可能不會有效。因此，公共衛生資訊的建構方式應使個人能夠做出知情明智的決定，並允許社區採取對疫情應對措施擁有他們自主權的行動；由於無法獲得疫苗，它們不應被視為係一種補償性反應。其次，對於未經訓練的個人來說，區分具感染性和非感染性不同情況下所引起的皮膚病變可能具有挑戰性。因此，風險溝通應著重於教育人們採取保護措施，提供在出現潛在症狀時去哪裡進行檢測的信息，並提出建議在感染的情況下採取有效的隔離措施，而不是依靠個人識別病變或自行做出隔離決定。
這些數據與非洲當前局勢的相關性可能較低。非洲聯盟目前疫情的流行病學正在演變，13個成員國報告了病例，且病例數持續上升。目前，MSM並不是這次疫情中最脆弱的族群；相反地，在剛果民主共和國，兒童（<15 歲）佔病例數的 66%，且佔 mpox 相關死亡人數的 82%。在剛果民主共和國南基伍省的一組聚集性病例中，女性性工作者佔 226 例感染者中的 29%。鑑於性工作者依靠密切的身體接觸來維持其經濟生存，他們的自我保護之選擇受到嚴重限制。此次疫情與2022-23年在全球MSM 中所爆發的疫情之差異，凸顯了 MPOX 疫苗接種的迫切需求。
目前非洲的MPOX疫情使MPOX成為更複雜的公共衛生挑戰。儘管事實證明，風險溝通和社區參與在 2022-23 年全球疫情爆發期間可以有效減少特定群體的傳播，但僅靠此類策略可能並不適用於或並不足以滿足非洲的情況。然而，如果未來的疫情有像2022 年那樣對MSM 族群產生更廣泛的影響，這些策略可能會再次發揮作用。解決mpox危機需要多方面的方法，確保公平地獲得疫苗和衛生保健服務，增強監測和診斷能力，並增加研究投資，以加深我們對病毒進化及其對MPOX流行病學變化之影響的了解。
我們聲明不存在競爭利益。
*Marc C Shamier、Kai J Jonas m.shamier@erasmusmc.nl 伊拉斯姆斯大學醫學中心病毒科學系，荷蘭，鹿特丹 3015GD (MCS)；馬斯特里赫特大學工作與社會心理學系，荷蘭，馬斯特里赫特 (KJJ)
Mpox control strategies: using behaviour change
to complement, not replace, vaccination
www.thelancet.com/infection Vol 24 December 2024 / Published Online September 18, 2024 https://doi.org/10.1016/ S1473-3099(24)00614-5
On Aug 13, 2024, the Africa Centres for Disease Control and Prevention declared mpox a Public Health Emergency of Continental Security in Africa. The following day, mpox was declared a Public Health Emergency of International Concern by WHO. The transmission of monkeypox virus (MPXV) clade I has increased substantially since 2023, with most cases reported in DR Congo. With 738 deaths reported in 2023 and more than 600 as of Aug 31, 2024, mpox mortality in the African Union during this period has surpassed the global mortality during the 2022–23 clade IIb outbreak, which primarily affected gay, bisexual, and other men who have sex with men (MSM). The emergence of a new subclade, Ib, underscores the crucial need for further research to understand the effect of the mutations that led to this new subclade on MPXV transmission dynamics and mpox disease severity. To curb the clade IIb outbreak in 2022–23, several factors were of relevance: natural immunity after MPXV infections, immunisation with the modified vaccinia virus Bavarian Nordic vaccine, the availability of diagnostic testing, and behaviour change.
In The Lancet Infectious Diseases, Mateo Prochazka and colleagues6 present data from a retrospective survey conducted among participants identifying as gay men, bisexual men, men who have sex with men, as transgender, or as non-binary in 23 countries between May 19 and May 31, 2023, showing that 50·9% of participants adjusted their sexual behaviour in response to the global MPXV clade IIb outbreak. These behavioural adaptations included reducing the number of sexual partners (93·2%) and, among those reporting engaging in these activities, avoiding group sex (88·4%), sex-on-premises venues (84·6%), and chemsex (53·6%). These changes persisted for 4 months or longer in more than half of the participants. In the event of a future resurgence of mpox with a rapid increase in transmission, 79·8% of participants expressed a willingness to adapt their sexual behavior. The findings of Prochazka and colleagues6 are consistent with several previous studies among MSM in different regions. The authors concluded that their study supports the hypothesis that behavioural changes, along with natural immunity, were the primary drivers of the rapid decline in MPXV clade IIb transmission among MSM at the end of 2022. Vaccination campaigns began after the outbreak had peaked, and this together with the decline in transmission in regions with lower vaccination rates suggest that vaccination alone was unlikely to be the primary factor in controlling the outbreak.
These data are crucial for informing public health policy in the event of resurgence of mpox among MSM, and highlight the importance of risk communication and community engagement. During the global 2022–23 mpox outbreak, several key lessons were learned about risk communication and community engagement in the context of sexually transmitted infections. First, directives aimed at specific groups to modify their sexual behaviour might not be effective. Therefore, public health messages should be framed in a way that means they empower individuals to make informed decisions and allow communities to take ownership of their response to an outbreak; they should not be presented as a compensatory response due to a lack of access to vaccines. Second, distinguishing between skin lesions caused by different infectious and non-infectious conditions can be challenging for untrained individuals. Consequently, risk communication should focus on educating people on protective measures, providing information on where to get tested if potential symptoms arise, and advising on effective isolation practices in case of infection, rather than relying on individuals to identify lesions or make their own decisions about isolation.
The relevance of these data to the current situation in Africa is likely to be low. The epidemiology of the ongoing outbreak in the African Union is evolving, with cases reported in 13 member states and the number of cases continuing to rise. Currently, MSM are not among the most vulnerable populations in this outbreak; instead, children ( <15 years) account for 66% of cases and 82% of mpox-related deaths in DR Congo. Behaviour modulation in children could be challenging. In a cluster of cases in South Kivu, DR Congo, female sex workers accounted for 29% of the 226 infections. Given that sex workers rely on close physical contact for economic survival, their options for self-protection are severely limited. Additionally, concerning data on adverse pregnancy outcomes in pregnant women with clade I mpox underscore the urgent need for targeted public health interventions. The differences between this outbreak and the global 2022–23 outbreak among MSM underline the urgent need for mpox vaccination.
The current mpox outbreak in Africa has rendered mpox a much more complex public health challenge. Although risk communication and community engagement proved effective in reducing transmission in specific groups during the global 2022–23 outbreak, such strategies alone might not be applicable to, or sufficient in, the African context. However, these strategies could become useful again if future outbreaks more widely affect MSM populations, as occurred in 2022. Addressing the mpox crisis will require a multifaceted approach that ensures equitable access to vaccines and health-care services, enhances surveillance and diagnostic capacities, and increases investment in research to enhance our understanding of viral evolution and its effect on the shifting epidemiology of mpox.
We declare no competing interests.
*Marc C Shamier, Kai J Jonas m.shamier@erasmusmc.nl Department of Viroscience, Erasmus University Medical Center, 3015GD Rotterdam, Netherlands (MCS); Department of Work and Social Psychology, Maastricht University, Maastricht, Netherlands (KJJ)