知道猴痘是一種性傳播感染，這有助於保護人們
在美國，男男性行為者中的黑人和拉丁裔男性最容易感染猴痘
作者：Steven W. Thrasher / 2022 年 8 月 18 日/《科學美國人》/ 財團法人台灣紅絲帶基金會編譯
圖片來源：Andriy Popov/Alamy Stock Photo
隨著來自世界各地的數據不斷湧現，誰受到最近爆發的猴痘 (MPX) 影響的清晰畫面正在顯現：在非洲以外，99% 的病例發生在男性身上，92% 到 98% 發生在自認為男男性行為者的男性身上。此外，歐盟、美國和英國的許多病例都發生在感染愛滋病毒的男性身上。
在美國，MPX 絕大多數影響著與男男性行為者中的黑人和拉丁裔男性。如果不糾正這種動態，這種種族差異將變得更糟，正如我的研究顯示在愛滋病毒上已經發生過了。
此種情景又再次發生了。在芝加哥，我打了一針 MPX 疫苗，幾乎每個人都在排隊，但我和一個朋友都是白人。來自朋友和新聞機構的報導證實，美國一些有錢的男同性戀者甚至前往加拿大接種疫苗。
結果？ MPX 在男男性行為的白人男性中已經消退，並在同樣行為的黑人和拉丁裔男性中匯集。
在機構內部，甚至在一些 LGBTQ 圈子內部，我遇到了數量驚人的關於明確解決這些明顯感染途徑的衝突。說出誰受到影響以及傳播是如何發生的並不是恐同或種族主義。相較於不去研究、預防和解決傳播是如何發生的，將使人們無法去理解如何預防感染，允許不必要擔憂的發生，並加劇種族主義和恐同症等社會健康決定因素。
有足夠的證據去緊急研究這種形式的 MPX 如何透過生殖器分泌物或皮膚與皮膚的摩擦傳播，這或許可以解釋為什麼在肛交期間接受型性伴侶存在著特殊風險。
對當前文獻進行清醒的回顧，再加上根植於酷兒健康和種族平等的富有同情心的公共衛生反應，可以在這場衛生緊急情況下闡明報告和保護人們的最佳途徑。
當我開始閱讀有關 MPX 爆發的研究時，我假設它的移動方式一定有性成分存在。我從未見過任何的病毒是與一項活動如此地相關，甚至是愛滋病毒。
我開始認為 MPX 是一種性傳播感染。這對我來說沒有爭議，我也不認為任何這樣的分類意味著 MPX 只會在性方面移動。十多年來，我研究了多種被疾病控制和預防中心歸類為性傳播感染或 STI（包括 HIV、肝炎和皰疹）的病毒，這些病毒具有多種傳播方式。
但重要的是要了解感染是如何透過性傳播來研究它們的運作原理並儘可能防止傳播。
在過去的幾個月裡，通常出於善意但最終被誤導的信念，將 MPX 命名為 STI 引起了相當大的反對，即這樣做會增加恥辱感。正如醫學人類學家哈里斯·所羅門（Harris Solomon）所說的一個反對意見，在於美國人是如何將性視為是一種身份而不是一種行為有關。因為我們經常將性與你是誰混為一談，而不是將其視為你所做的事情，所以許多人將診斷一個行為的風險說成了一些關於人的事情。但是，雖然性是生活中必不可少的一部分，但它也是一種像騎自行車或吸煙一樣的行為，有其自身的風險和樂趣——必須在努力保護公眾健康的同時進行嚴格的研究。
另一種動力是認為同志的性都是如此糟糕和可恥的，絕不能談論它，在強調公共衛生緊急情況下更不用去說了。無論有意與否，這些都是恐同的。
7 月下旬發表在 BMJ 上的一項研究發現，倫敦 197 例 MPX 病例中有 196 例發生在被確認為男男性行為者的人群中，這在英國和許多其他非流行國家看到在同性戀、雙性戀和其他男男間性行為為者中造成了史無前例的猴痘病毒之社區傳播」。研究中非常生動的照片說明了這種 MPX 變異株（與西非和中非從動物傳播到人類的地方性流行之病毒不同）如何顯示出顯著變化。
以前感染 MPX 的人，無論他們身體的哪個部位接觸到了病毒，會在手、臉、背和腳上出現病變。但在 BMJ 論文中，生殖器和肛周區域也出現了病變，顯示這種病毒有不同的症狀，亦表明它的傳播方式也可能不同。 （這些照片顯示的症狀如此嚴重，以至於他們打消了很多異性戀者在暗中受苦並且因為尷尬而不求醫的觀念。）
新的爆發並非完全史無前例。 2017 年，一位名叫 Dimie Ogoina 的奈及利亞醫生診斷出一位患有 MPX 的人，正如他告訴美國國家廣播電台 (NPR) 的那樣，這是該國 38 年來的首例病例。 （後來，他證實該患者是被另一個人而不是動物感染的。）然後奧戈伊納發現了一次爆發流行，幾乎完全由未接觸動物的年輕人組成。許多人出現生殖器損傷和潰瘍。他在 2019 年發表了他的研究結果，其中包括他的觀察結果：「雖然人類猴痘的性傳播作用尚未確定，但在其中一些患者中，性傳播是合理的，透過性交期間的皮膚與皮膚的密切接觸或透過生殖器分泌物傳播」。但全球科學界沒有人注意到他的警告。
本月《剌胳針》雜誌對馬德里和西班牙巴塞隆那的 181 例猴痘病例進行的一項研究支持了性傳播的案例。在被確定為男男性行為者的 92% 病例中，「參與者報告接受型肛交性行為者比其他人更有可能在發生皮膚病變之前出現早期全身症狀。一種解釋是，肛交可能會損傷上皮細胞（一層非常薄的組織）並使血液進入，從而在局部病變尚未發展的早期階段導致更大的病毒血症」。儘管作者得出結論，「關於猴痘是否透過精液和陰道分泌物進行性傳播存在疑問」，但他們指出，「梅毒和單純皰疹等性傳播感染的擴展定義包括 [當病原體] 透過皮膚或粘膜表面擦傷而傳播」。
性交過程中的皮膚接觸傳播是一種性傳播感染。
在美國，我們很難談論一般的性，特別是同性戀。我工作的大學向其整個社區發送了一封電子郵件並在網上發布了一條消息，上面寫著：「猴痘不是一種性傳播感染或疾病，也與性取向無關」——其表達方式將性視為一個身份，而不是一個行為動作。
與此同時，美國的病毒不僅在整個 MSM 社區內傳播，而且在黑人和拉丁裔 MSM 中傳播尤其如此。據《華盛頓郵報》報導，在美國疾病控制與預防中心按種族和民族劃分的第一批數據中，在已知這些信息的病例中，32% 是拉丁裔，26% 是黑人。 8 月 10 日，《亞特蘭大憲法報》報導，喬治亞州公共衛生部的數據顯示，令人震驚的是 82% 的 MPX 病例為黑人。同一天，北卡羅來納州衛生與公眾服務部報告了該州的 122 例病例——「全部為男性，幾乎全部為男男性行為者」，「70% 的病例……在黑人/非洲裔美國男性中，白人男性佔 19%」。
北卡羅來納州補充了我一直在等待看到的數據：「只有 24% 的疫苗接種給了黑人/AA [非洲裔美國人]，而 67% 的疫苗接種給了白人」。
常常有些人天真地希望治療傳染病的藥物或疫苗能使種族差異消失。但是，在 COVID 和 HIV 感染者中，誰有風險與誰接種疫苗之間存在這種反比關係。如果不加以糾正，這意味著種族健康差異將變得更糟，病毒將更多地集中在我所說的「病毒下層階級」中。
在我自己的研究中，我發現當 CDC 在 1980 年代開始研究愛滋病的種族差異時，黑人男性被診斷為愛滋病的可能性是白人男性的三倍。到 1996 年，也就是 HIV 藥物上市的那一年，這一比例翻了一番，達到大約 6 比 1。到 2015 年，它已增加到幾乎九比一。這是因為 1996 年白人男同性戀者開始服用 HIV 藥物，這大大降低了他們社交網絡中的病毒載量。黑人在很大程度上沒有得到藥物——因此病毒在黑人中傳播得更多，並集中在該人群中，並且差距擴大了。
正如上週發表在《自然醫學》雜誌上的一項比利時之研究顯示，要能更準確地了解 MPX 的移動方式，一種方法是在男男性行為者的常規性傳播感染篩查中對其進行測試。研究人員「使用猴痘病毒 (MPXV) PCR 分析法回顧性篩選了 224 份為淋病和衣原體檢測而收集的樣本，並確定了來自四名男性的 MPXV DNA 陽性樣本」，儘管「在取樣時，一名男性患有疼痛皮疹，三名男子沒有報告任何症狀」。與此同時，《內科學年鑑》上的一項法國研究對 200 名接受 STI 檢測的男性進行了肛門直腸拭子檢測，發現其中 13 人（6.5%）對 MPX 呈無症狀陽性。
我們還需要緊急研究為什麼即使是無法檢測到 HIV 水平的人——他們的HIV病毒載量如此之低，不會對其免疫系統造成傷害，也不會傳染給其他人——在 MPX 病例中的所占比例卻仍然如此之高。
具有諷刺意味的是在公共場所對 MPX 不必要的恐慌，人們應該在地鐵中為 COVID 戴上口罩。導致 COVID 的病毒 SARS-CoV-2 是透過空氣傳播的，並已經殺死了 100 萬美國人。 MPX 不是以同樣的方式在空氣中傳播的，它幾乎完全是透過自己的性傳播，它還沒有殺死任何美國人。
雖然 CDC 沒有將 MPX 列入其性傳播病毒列表，但卻奇怪地開始稱其為性傳播病毒。無論如何，這項研究很清楚：雖然美國 1% 到 6% 的 MPX 病例可能以其他方式傳播，但 94% 的感染是在自我認同為男男性行為者中透過性傳播，尤其是在黑人和拉丁裔男性中。這沒什麼好羞恥的，也沒什麼好隱瞞的。在突發公共衛生事件期間，這是需要解決的問題，應以我們的需求為中心，積極開展運動以保護那些應得到尊嚴的人，。
這是一篇觀點和分析文章，作者所表達的觀點不代表《科學美國人》的觀點。
Monkeypox Is a Sexually Transmitted Infection, and Knowing That Can Help Protect People
In the U.S., Black and Latino men who have sex with men are most vulnerable to monkeypox
By Steven W. Thrasher on August 18, 2022 / Scientific American
Credit: Andriy Popov/Alamy Stock Photo
As data come in from around the world, a clear picture is emerging of who is being affected by the recent outbreak of monkeypox (MPX): Outside Africa, 99 percent of the cases have been in men, and 92 to 98 percent have been in self-identified men who have sex with men. Also, many of the cases in the Europe Union, the U.S. and the U.K. have been in men who are living with HIV.
In the U.S., MPX is overwhelmingly affecting Black and Latino men who have sex with men. If this dynamic is not corrected, this racial disparity will grow worse, as my research has shown has happened with HIV.
It’s happening again. In Chicago, where I got one MPX vaccine shot, almost everyone in line but me and a friend were white. Reports from friends and news organizations corroborate that some gay men of means in the U.S. are even traveling to Canada to get vaccinated.
The result? MPX is already receding among white men who have sex with men and pooling among Black and Latino men who do so.
I have encountered a surprising amount of conflict—within institutions and even inside of some LGBTQ circles—about explicitly addressing these obvious paths of infection. Naming who is being affected and how transmission is happening is not homophobic or racist. Rather not naming, researching, preventing and addressing how transmission is happening will keep people from understanding how to prevent infection, allow unnecessary worry, and exacerbate racist and homophobic social determinants of health.
There is sufficient evidence to urgently study how this version of MPX may be transmitted through genital secretions or skin-to-skin friction, perhaps accounting for why there is a particular risk among receptive sex partners during anal intercourse.
A clearheaded review of the current literature, coupled with compassionate public health responses rooted in queer health and racial equity,
When I started reading research on the MPX outbreak, I hypothesized that there must be a sexual component to how it was moving. I have never seen any virus so connected to one activity, not even HIV.
I began thinking about MPX as a sexually transmittied infection. This didn’t feel controversial to me, nor did I think any such categorization would mean MPX would only move sexually. For more than a decade, I have studied a variety of viruses categorized by the Centers for Disease Control and Prevention as sexually transmitted infections, or STIs, (including HIV, hepatitis and herpes) that have many modes of transmission.
But it’s important to understand how infections move sexually to research how they work and to prevent transmission whenever possible.
In the past few months, there has been considerable backlash to naming MPX an STI out of the usually well-intentioned but ultimately misguided belief that doing so will increase stigma. One objection, as medical anthropologist Harris Solomon has put it, has to do with how people in the U.S. treat sex as an identity and not as an action. Because we often conflate sex with who you are rather than seeing it as something you do, many people think diagnosing the risk of an action says something about people. But while sex is a necessary part of life, it is also an action like riding a bike or smoking, with its own risks and pleasures—and it must be studied rigorously while trying to protect public health.
The other dynamic is believing that gay sex is so bad and shameful, it must not be spoken about, let alone highlighted during a public health emergency. Intended as such or not, this is homophobic.
A study published in the BMJ in late July found 196 of 197 cases of MPX in London were in people who identified as men who had sex with men, creating an “unprecedented community transmission of monkeypox virus among gay, bisexual, and other men who have sex with men seen in the UK and many other non-endemic countries.” The very graphic photographs in the study illustrated how this variant of MPX—which differs from the endemic virus that jumped from animals to humans in West and Central Africa—has shown a significant change.
Previously people infected with MPX would get lesions on their hands, face, back and feet, regardless of where on their body they had come into contact with the virus. But in the BMJ paper, lesions also appeared on the genital and in perianal area, showing that this form of the virus had different symptoms and suggesting it was perhaps transmitting differently, too. (The photographs show symptoms so severe that they put to rest any notions that large numbers of straight people are secretly suffering and not seeking medical attention out of embarrassment.)
The new outbreak is not entirely unprecedented. In 2017 a Nigerian doctor named Dimie Ogoina diagnosed someone with MPX who was, as he told NPR, the first case in his country in 38 years. (Later, he confirmed that the patient had been infected by another human rather than an animal.) Then Ogoina found an outbreak composed almost entirely of young men who weren’t handling animals. Many presented with genital lesions and ulcers. He published his findings in 2019, including his observation that “although the role of sexual transmission of human monkeypox is not established, sexual transmission is plausible in some of these patients through close skin to skin contact during sexual intercourse or by transmission via genital secretions.” But the global scientific community didn’t heed his warning.
A study in the Lancet this month of 181 monkeypox cases in Madrid and Barcelona, Spain, bolsters the case of sexual transmission. Among the 92 percent of cases who identified as men who have sex with men, “participants reporting anal-receptive sex were more likely than others to have early systemic symptoms before developing skin lesions. One explanation is that anal sex might damage the epithelium [a very thin layer of tissue] and enable blood entry, allowing greater viraemia at an early stage when local lesions have not yet developed.” While the authors conclude, “There are questions about whether monkeypox is sexually transmitted via semen and vaginal secretions,” they note that “the extended definition of sexually transmitted infections such as syphilis and herpes simplex includes [when pathogens] are transmitted through superficial abrasions in the skin or mucous membranes.”
Skin-on-skin transmission during sex is a sexually transmitted infection.
In the U.S., we have trouble talking about sex in general and gay sex in particular. The university where I work sent an e-mail and posted a message online to its entire community that said, “Monkeypox is not a sexually transmitted infection or disease, nor is it linked to sexual orientation”—phrasing in which sex was dealt with as an identity, not an action.
Meanwhile the virus in the U.S. is not just moving within the MSM community as a whole but particularly among Black and Latino MSM. In the first data broken down by race and ethnicity by the CDC, as reported by the Washington Post, among cases in which this information was known, 32 percent were Latino, and 26 percent were Black. On August 10 the Atlanta Journal-Constitution reported that data from the Georgia Department of Public Health showed an astounding 82 percent of MPX cases were Black. The same day the North Carolina Department of Health and Human Services reported 122 cases in that state—“all in males and nearly all in men who have sex with men,” with “70% of cases … in Black/African American men and 19% in White men.”
North Carolina added data I’ve been waiting to see: “only 24% of vaccines have gone to Black/AA [African American] recipients, while 67% have gone to White recipients.”
Often some people naively hope a drug or a vaccine to treat an infectious disease will make racial disparities disappear. But this kind of inverse relationship between who is at risk and who gets vaccinated has been seen with COVID and HIV. If uncorrected, it means racial health disparities will get worse, pooling the virus even more in what I call a “viral underclass.”
In my own research, I found that when the CDC began looking at racial disparities in AIDS in the 1980s, Black men were about three times more likely to have an AIDS diagnosis than white men. By 1996, the year HIV medications became available, the ratio had doubled to about six to one. By 2015, it had increased to almost nine to one. This is because in 1996 white gay men started getting HIV drugs, which lowered viral loads dramatically in their social networks. Black people largely did not get the drugs—and so the virus moved more among Black people and concentrated in that population, and the disparity grew.
As a study in Belgium published in Nature Medicine last week illustrates, one way to more precisely understand how MPX is moving would be to test for it during routine STI screenings for men who have sex with men. The researchers “retrospectively screened 224 samples collected for gonorrhoea and chlamydia testing using a monkeypox virus (MPXV) PCR assay, and identified MPXV DNA-positive samples from four men,” even though, “at the time of sampling, one man had a painful rash, and three men had reported no symptoms.” Meanwhile a French study in the Annals of Internal Medicine performed anorectal swabs on 200 men undergoing STI testing and found 13 of them—6.5 percent—were asymptomatically positive for MPX.
We also need to urgently study why even people with undetectable levels of HIV—who have a viral load so low that it is causing no harm to their immune systems and can’t be transmitted to others—are still so overrepresented among MPX cases.
The irony of needless panic about MPX in public places is that people should be masking in subways for COVID. SARS-CoV-2, the virus that causes COVID, is airborne and has killed a million of Americans. MPX, which is not airborne in the same way, has almost exclusively transmitted itself sexually, and it has not yet killed any Americans.
While the CDC does not include MPX on its list of sexually transmitted viruses, it has bizarrely started calling it sexually transmissible. Regardless, the research is clear: while 1 to 6 percent of cases of MPX in the U.S. may be transmitting in other ways, 94 percent of infections are moving sexually among self-identified men who have sex with men, especially among Black and Latino men. This is nothing to be ashamed of or to hide; it is something to be addressed to protect people who deserve the dignity of a proactive campaign that centers our needs during a public health emergency.
This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.