www.thelancet.com/infection Vol 24 June 2024 / 線上發布 2024 年 5 月 1 日 https://doi.org/10.1016/ S1473-3099(24)00287-1
在COVID-19 大流行之後，人類在2022 年經歷了另一場健康威脅流行病的出現。這種威脅來自人類Mpox（以前稱為猴痘）病毒，儘管這種病原體於 1958 年被發現，但在最近的發展之前，歷史上一直受到很少的關注。1970 年首次在人類中被報導，此後由於傳播途徑和傳播機制改變而導致的疾病，以及2022 年病例數增加，又重新引起了人們的興趣。緊隨著持續蔓延至流行國家和增加群聚中的病例數後，世衛組織宣布mpox疫情為國際公共衛生緊急關注事件（PHEIC）。隨著病例數量的下降，世衛組織於 2023 年 5 月將Mpox疫情降級為不再是國際關注的突發公共衛生事件。儘管做出了這項聲明，但一些國家仍繼續報告病例。
儘管早期mpox的傳播是撒哈拉以南非洲地區的地方病，並且抑或是由於人類與猴子的互動或者是受到感染者之間的偶然接觸引起的人畜共通傳播所驅動的，但在2022年，世界見證了一種潛在的全球流行病的出現，這種流行病是由男男之間的性接觸所驅動的。
2023 年 9 月，剛果民主共和國南基伍省再次出現了 MPOX流行，其流行病學特徵顯示異性的傳播和擴散。先前，有跡象顯示剛果民主共和國的傳播是由同性戀互動驅動的。本評論使用常規方法描述了南基伍省當前 MPOX 疫情的流行病學監測數據，並強調了傳播動態似乎發生了變化，從傳統的人與野生動物互動和人與人之間的偶然傳播，到異性傳播，以及對於跨境流行和潛在全球傳播的可能影響。
2023年9月28日至2024年3月3日期間，南基伍省調查了226件疑似mpox病例。最常見的徵兆或症狀包括：皮疹（100%）、發燒（59%）、淋巴結腫大（40%）、喉嚨痛（26%）、頭痛（23%）、咳嗽（22%）、肌肉疼痛（ 22 %）和口腔潰瘍（14%），患者沒有性別差異。超過一半的病例是女性 (53·8%)，這一結果與先前研究中男性是主要受影響的結果不同，但與中非目前的I 分支病毒株之流行病學一致。很明顯，異性性傳播可能會推動該地區的傳播率，這與同性戀的傳播不同，特別是在男男性接觸者中，這是 2022 年高感染率的主要驅動因素。女性的高盛行率可能會引入另一種傳播途徑（即垂直傳播），從而使控制變得更複雜，垂直傳播會導致不良妊娠結局。此外，目前女性性工作者在這群人的病例中所佔比例很大（29%），這一事實也支持了異性傳播擴散的證據（圖）。
儘管據推測 Mpox 可以透過性傳播，但這可能係透過同性戀途徑傳播，而且主要是在 MSM 中傳播。而該世代的研究結果顯示，與異性性傳播（92%）和同性戀傳播（4%）相關傳播風險的增加，其中女性受影響最大。這種轉變可能是由於分支 I 相較於分支 II，在剛果民主共和國占主導地位且嚴重。而分支 II 則是在西方國家和奈及利亞更為溫和且更為常見，影響著男男性行為者間的流行。性接觸本身是否是一種傳播途徑，或者只是透過相關的皮膚接觸來增強傳播，仍有待充分研究。但無論如何，這些研究結果對控制該地區的性傳播感染具有重要意義，該地區婦女愛滋病毒感染率仍然很高，而該地區與武裝衝突相關的性暴力更進一步加劇了這種感染率。
而患者的中位年齡為 21 歲，其中大多數 (59%) 年齡在 15-29 歲之間。這項發現與最近報告的情況一致，即患者的中位年齡有所上升，而早年則以幼兒受影響最嚴重。然而，中位數年齡低於其他地方所發現的年齡。這項發現可以解釋為，在這個以年輕手工採礦人口為主的人群中，天花疫苗免疫力的下降，同時也存在著潛在的性傳播。
傳播動態和高危險群盛行率的轉變，讓人想起愛滋病毒/愛滋病出現流行的歷史，最初認為這種流行病是從猴子轉移到人類的，最初的高盛行率在男男性行為者中佔主導地位，後來則主要透過異性接觸傳播。同樣，由於邊界的漏洞，跨境傳播的可能性（最初在烏干達）仍然很高，因為礦山周圍有非正規工人，而且由於不安全而導致群眾流動增加。光是 2022 年，就有超過 6 萬名難民從剛果民主共和國越境進入烏干達，而且這場大規模運動仍在持續。
南基伍省Mpox疫情的傳播動態不斷變化，凸顯了制定適應性強、創新全球衛生策略的必要性。這些策略應強調增強本地檢測能力，可能透過部署行動診所進行現場檢測，而不是依賴樣本運輸到遙遠的實驗室。個案管理的創新，例如策略性使用抗病毒藥物以及個人化和風險知情的社區參與方法，對於解決Mpox死灰復燃的問題至關重要。此外，迫切需要加快有效的Mpox疫苗的研究、開發和傳播，以保護全世界的高危險群。創新方法還可以包括利用數位健康技術進行即時監測，並使用人工智慧來預測疫情爆發模式，從而加強預防措施和應對策略。
我們聲明不存在競爭利益。
*Patrick DMC Katoto、Winters Muttamba、Esto Bahizire、Espoir Bwenge Malembaka、Henry Kyobe Bosa、Dieudonné Mwamba Kazadi、Gaston Lubambo、Freddy Belesi Siangoli、Barnabas Bakamutumaho、Misaki Wayera、Don Jamaladia、Don Juleb、Badbunyalr.勒布、布魯斯·基倫加、讓-雅克·穆延貝-塔姆夫姆katoto.chimusa@ucbukavu.ac.cd剛果民主共和國布卡武天主教布卡武大學醫學院熱帶病與全球健康中心（PDMCK、EB、EBM）；南非開普敦斯泰倫博斯大學醫學與健康科學學院全球衛生系流行病學與生物統計學司 (PDMCK)； Cochrane 南非、南非醫學研究理事會，南非開普敦 (PDDMK)；研究與創新部，麥克雷雷大學肺臟研究所，烏干達坎帕拉（WM、HKB、BK）；聖安德魯斯大學醫學院，聖安德魯斯，法夫，英國 (WM)； Centre de Recherche en Sciences，Naturelles de Lwiro，布卡武，剛果民主共和國 (EB)；約翰霍普金斯大學彭博公共衛生學院流行病學系，美國馬里蘭州巴爾的摩 (EBM)；烏干幹達政府衛生部，烏干達坎帕拉（HKB）；牛津大學凱洛格學院，英國牛津（HKB）；剛果民主共和國金薩沙衛生部國家衛生研究所 (DMK)；剛果民主共和國衛生部布卡武省省級衛生司（GL、FBS）；烏干達病毒研究所免疫疾病科，烏干達坎帕拉（BB）；烏干達坎帕拉麥克雷雷大學生物醫學學院、健康科學學院（MW）；剛果民主共和國卡南加卡薩伊聖母大學醫學院 (DJML)；剛果民主共和國衛生部，國家生物醫學研究所 (INRB)（DM-B、PM、J-JM-T）；加拿大安大略省漢密爾頓麥克馬斯特大學醫學系（ML）；麥克雷雷大學健康科學學院醫學系，烏干達坎帕拉（BK）
圖：Mpox個案的職業別和性別之分佈
Shifting transmission patterns of human mpox in South Kivu, DR Congo
www.thelancet.com/infection Vol 24 June 2024 /
Published Online May 1, 2024 https://doi.org/10.1016/ S1473-3099(24)00287-1
In the wake of the COVID-19 pandemic, humanity experienced the emergence of another epidemic health threat in 2022. That threat came from human mpox (formerly known as monkeypox) virus—an agent that despite its discovery in 1958, has historically received low attention until recent developments. First reported in humans in 1970, there has since been renewed interest in the disease due to altered transmission and spread mechanisms, and the increased number of cases in 2022. WHO declared mpox outbreak a Public Health Emergency of International Concern (PHEIC), following rapid and sustained spread beyond the endemic countries and increases in the number of cases in clusters. Following the decline in number of cases, in May 2023, WHO downgraded the mpox outbreak as no longer a PHEIC. Despite this declaration, cases continue to be reported in several countries.
Although earlier transmission of mpox was endemic to sub-Saharan Africa and driven by either zoonotic spread from human interactions with monkeys or casual contact among infected humans, in 2022 the world witnessed the emergence of a potential global pandemic driven by sexual contact among men who have sex with men (MSM).
In September 2023, the re emergence of mpox with an epidemiological profile suggestive of heterosexual transmission and spread was noted in the province of South Kivu, in DR Congo. Previously, there had been an indication that the transmission in DR Congo was driven by homosexual interaction. This commentary describes the epidemiology of the current mpox outbreak in South Kivu using routine www.thelancet.com/infection Vol 24 June 2024 among MSM.6 surveillance data and highlights what appears to be altered transmission dynamics from the traditional human–wild interactions and casual human-to-human transmission, to heterosexual transmission and the likely implications for cross border and potential global spread.
Between Sept 28, 2023 and March 3, 2024, 226 suspected mpox cases were investigated in South Kivu. The most common signs or symptoms included: skin eruption (100%), fever (59%), lymphadenopathy (40%), sore throat (26%), headache (23%), cough (22%), muscle pain (22%), and mouth ulcers (14%), with no sex difference. More than half of the cases were women (53·8%), a result that diverges from previous studies where men were predominantly affected, yet aligns with the current epidemiology of Clade I in Central Africa. It appears apparent that heterosexual transmission could be driving the transmission rates in this region, unlike homosexual transmission especially in MSM, which was the main driver for the high infection rates in 2022. High prevalence in women could complicate control by introducing another route of transmission—ie, vertical transmission, which presents with adverse pregnancy outcomes.4 Furthermore, evidence of heterosexual transmission spread is supported by the fact that currently, female sex workers constitute a big proportion of cases (29%) in this cluster (figure).
Although it has been postulated that mpox could be sexually transmitted, this would be via the homosexual route, and largely among MSM. The findings from this cohort suggest increased risk of transmission associated with heterosexual (92%) and homosexual transmission (4%), with women largely affected. The shift might be due to Clade I’s predominance and severity in DR Congo compared with Clade II, which is milder and more common in Western countries and Nigeria, influencing the outbreak Whether or not sexual contact by itself serves as a route of transmission or simply enhances transmission by associated skin to-skin contact remains to be fully investigated. Regardless, these f indings have implications for control of sexually transmitted infections in a region where the prevalence of HIV among women remains high, which is further exacerbated by sexual violence associated with armed conflict in the region.
The median age of the patients was 21 years, with most (59%) aged between 15–29 years. This finding is in keeping with what has been reported recently, a rise in median age of patients as opposed to earlier years where young children were the most affected. However, the median age is lower than what has been found elsewhere. This finding could be explained by waning immunity from smallpox vaccination in this predominantly young artisanal mining population, alongside potential sexual transmission.
The shift in transmission dynamics and the prevalence in at-risk groups is reminiscent of the historical emergence of the HIV AIDS epidemic that was originally postulated to have transferred over from monkeys to humans,10 with its initial high prevalence predominating among MSM and later transitioning majorly by heterosexual contact transmission. Similarly, the possibility of cross border transmission, initially in Uganda given the porosity of borders, remains high because of informal workers around mines and increased mass movement arising from insecurity. In 2022 alone, over 60 000 refugees crossed into Uganda from DR Congo and this mass movement continues.
The shifting transmission dynamics of the mpox outbreak in South Kivu stresses the imperative for adaptable and innovative global health strategies. These strategies should emphasise enhanced local detection capabilities, potentially by deploying mobile clinics for onsite testing rather than relying on sample transportation to distant laboratories. Innovations in case management, such as the strategic use of antiviral medications alongside personalised and risk informed community engagement approaches, are pivotal for tackling the resurgence of mpox. Furthermore, there is an urgent need to expedite the research, development, and dissemination of effective mpox vaccines to safeguard at-risk populations worldwide. An innovative approach could also include leveraging digital-health technologies for real time surveillance and using artificial intelligence to predict outbreak patterns, thus enhancing both preventive measures and response strategies.
We declare no competing interests.
*Patrick DMC Katoto, Winters Muttamba, Esto Bahizire, Espoir Bwenge Malembaka, Henry Kyobe Bosa, Dieudonné Mwamba Kazadi, Gaston Lubambo, Freddy Belesi Siangoli, Barnabas Bakamutumaho, Misaki Wayengera, Don Jethro Mavungu Landu, Daniel Mukadi-Bamuleka, Placide Mbala, Mark Loeb, Bruce Kirenga, Jean-Jacques Muyembe-Tamfum katoto.chimusa@ucbukavu.ac.cd
Center for Tropical Diseases and Global Health, Faculty of Medicine, Catholic University of Bukavu, Bukavu, Democratic Republic of the Congo (PDMCK, EB, EBM); Division of Epidemiology and Biostatistics, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa (PDMCK); Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa (PDMCK); Department of Research and Innovation, Makerere University Lung Institute, Kampala, Uganda (WM, HKB, BK); School of Medicine, University of St Andrews, St. Andrews, Fife, UK (WM); Centre de Recherche en Sciences, Naturelles de Lwiro, Bukavu, DR Congo (EB); Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA (EBM); Ministry of Health, Government of Uganda, Kampala, Uganda (HKB); Kellogg College, University of Oxford, Oxford, UK (HKB); Institut National de Santé Publique, Ministry of Health, Kinshasa, DR Congo (DMK); Division Provinciale de la Santé du Sud-Kivu, Ministry of Health, Bukavu, DR Congo (GL, FBS); Department of Immunisable diseases, Uganda Virus Research Institute, Kampala, Uganda (BB); School of Biomedical Sciences, College of Health Sciences, Makerere University, Kampala, Uganda (MW); Faculté de Médecine, Université Notre-Dame du Kasayi, Kananga, DR Congo (DJML); Institut National de Recherche Biomédicale (INRB), Ministry of Health, Kinshasa, DR Congo (DM-B, PM, J-JM-T); Department of Medicine, McMaster University, Hamilton, ON, Canada (ML); Department of Medicine, Makerere University College of Health Sciences, Kampala, Uganda (BK)