在經(jīng)歷了數(shù)十年的穩(wěn)步下降之后，性傳播疾?。⊿TI）在發(fā)達(dá)國(guó)家中出現(xiàn)了抬頭跡象。這一現(xiàn)象帶來(lái)的后果異常嚴(yán)重。例如梅毒，每年在全球都會(huì)引發(fā)超過(guò)20萬(wàn)例的死胎和嬰兒夭折，而且嬰兒在患病數(shù)年之后還會(huì)出現(xiàn)失明、癡呆或麻痹癥狀。性傳播疾病的再度猖獗有多方面的原因，包括未能堅(jiān)持使用避孕套以及非法消遣性藥物的濫用。與此同時(shí)，由于抗生素耐藥性的原因，包括淋病和志賀氏菌病在內(nèi)的一些普通性傳播疾病，正在變得越來(lái)越難治。在美國(guó)這個(gè)性傳播疾病發(fā)病率最高的發(fā)達(dá)國(guó)家中，疾病的蔓延每年所消耗的可預(yù)防醫(yī)療費(fèi)用達(dá)到了約160億美元。

這個(gè)問(wèn)題有多嚴(yán)重？

在美國(guó)，衣原體感染、淋病和梅毒這三種最常見(jiàn)、可治愈的性傳播疾病在2017年大幅增加了20多萬(wàn)例，將患者總數(shù)推升至近230萬(wàn)。以梅毒為例，美國(guó)依據(jù)報(bào)道的年發(fā)病率在近些年來(lái)將近翻了一番，從2012年的15.9例/10萬(wàn)人增至2017年的31.4例/10萬(wàn)人。在法國(guó)、比利時(shí)、愛(ài)爾蘭和英國(guó)，梅毒發(fā)病率也呈現(xiàn)出了類似趨勢(shì)。在澳大利亞，2016年淋病發(fā)病率較2012年增長(zhǎng)了63%。2007至2016年法國(guó)的發(fā)病率增長(zhǎng)了5倍，丹麥的發(fā)病率增長(zhǎng)了4倍。

增長(zhǎng)的原因何在？

原因很復(fù)雜。以梅毒為例：盡管每年約600萬(wàn)例的新增病例都分布在中低收入國(guó)家，但高收入國(guó)家的增幅最高。在這些國(guó)家中，梅毒已經(jīng)從一些高風(fēng)險(xiǎn)群體，例如同性戀和雙性戀男士向更廣泛的人群傳播。在美國(guó)，2013-2017年，女性早期梅毒患病比例飆升了156%。美國(guó)疾病防控中心稱，這一點(diǎn)與性化藥物使用的上升有關(guān)，例如使用麻黃堿或注射海洛因之類的毒品刺激自身與多名伴侶發(fā)生不安全性行為。同樣在歐洲，事實(shí)證明，稱為party and play （PnP）、chemsex或slamming的類似活動(dòng)成為了性工作和高風(fēng)險(xiǎn)性行為的推手，尤其是同性之間的性行為。

存在其他因素嗎？

是的。例如在美國(guó)，20世紀(jì)90年代中期之后男同性戀群體艾滋病死亡率的下降一直伴隨著梅毒病例的上升。最近，艾滋病傳播預(yù)防藥物（又稱艾滋病暴露前用藥或PrEP）的面世，完全有望降低這些男性群體中的新增病例數(shù)量。它還與不常使用避孕套有關(guān)，而避孕套是抵御其他性傳播疾病最有效的方式之一。對(duì)PrEP使用群體進(jìn)行更頻繁的性傳播疾病篩查測(cè)試會(huì)讓人們難以弄清楚此前未發(fā)覺(jué)或未治療的感染是否得到了確診或?qū)嶋H上是有所增加。更加頻繁的國(guó)際旅行和勞工遷移也意味著致病因子正在以更快的速度向更廣泛地區(qū)傳播。

有什么樣的后果？

每一種致病因子都具有其獨(dú)特的危險(xiǎn)性。例如，在患有梅毒、且未得到治療的孕婦中，出現(xiàn)流產(chǎn)、死胎或嬰兒夭折的概率高達(dá)40%。存活下來(lái)的嬰兒可能會(huì)出現(xiàn)畸形，包括骨骼缺陷、聽(tīng)力障礙以及會(huì)可能引發(fā)發(fā)育遲緩和癲癇的腦膜炎。自2013年以來(lái)，已報(bào)道的母嬰傳播梅毒病例在美國(guó)增長(zhǎng)了一倍多，在2017年達(dá)到了20年來(lái)的新高——918例，其中70%的病例分布于佛羅里達(dá)、加利福尼亞州、亞利桑那州、得克薩斯州和路易斯安那州。以衣原體為例，80%的感染都沒(méi)有什么癥狀，但它仍然可以通過(guò)性行為傳播。這種感染在女性中尤為嚴(yán)重。如果不加以治療，它可能會(huì)轉(zhuǎn)移至上生殖系統(tǒng)，導(dǎo)致盆腔炎性疾病，繼而引發(fā)子宮外孕、慢性疼痛和不孕。在子宮內(nèi)被感染的新生嬰兒可能會(huì)患上肺炎。支原體感染未得到治療的男性可能會(huì)患上關(guān)節(jié)炎。

抗藥性淋病有多嚴(yán)重？

非常嚴(yán)重。進(jìn)化后的細(xì)菌已經(jīng)能夠?qū)苟喾N抗生素，英國(guó)和澳大利亞分別出現(xiàn)了4例和2例已報(bào)道具有廣泛抗藥性的淋病。雖然細(xì)菌對(duì)于一些新出現(xiàn)的抗生素普遍較為敏感，但喉部感染的治療效果似乎要差一些。喉部的細(xì)菌可以在不經(jīng)意間通過(guò)親吻傳播，也讓這類感染難以杜絕。關(guān)鍵問(wèn)題在于，全球性病治療領(lǐng)域的主力軍頭孢曲松鈉正在失去其效力，因此加劇了抗藥性淋病出現(xiàn)的風(fēng)險(xiǎn)。當(dāng)這種疾病無(wú)法得到治療時(shí)，它可能會(huì)導(dǎo)致男性和女性的不孕不育，而且有可能導(dǎo)致致命的血液感染。

我們能做些什么？

經(jīng)驗(yàn)告訴我們，鼓勵(lì)使用避孕套還不足以抑制疾病的傳播。我們還需要新工具以及包括抗病毒和抗生素在內(nèi)的新治療劑。疫苗也可以作為一個(gè)重要的防御手段，它曾經(jīng)大幅降低了人乳頭狀瘤病毒和乙肝病例數(shù)量。對(duì)于皮膚皰疹和艾滋病疫苗的研究正在向前邁進(jìn)，而針對(duì)支原體、淋病、梅毒和滴蟲(chóng)等其他常見(jiàn)性傳播疾病的疫苗依然處于早期開(kāi)發(fā)階段。

世界其他地區(qū)是什么情況？

每一天都有100多萬(wàn)人感染性傳播疾病，其中大多數(shù)都分布于中低收入國(guó)家。一般來(lái)說(shuō)，性傳播疾病是衡量醫(yī)療服務(wù)可獲取性的一個(gè)指標(biāo)：測(cè)試或治療水平最差的群體有著最高的發(fā)病率。世界衛(wèi)生組織發(fā)現(xiàn)，女性性工作者、注射毒品使用者、同性戀人群以及變性女性最容易受到感染。在醫(yī)療站點(diǎn)提供更快、更可靠的測(cè)試將有助于疾病的早期檢測(cè)和治療，尤其是在發(fā)展中國(guó)家和偏遠(yuǎn)地區(qū)。（財(cái)富中文網(wǎng)）

譯者：馮豐

審校：夏林

Sexually transmitted infections (STIs) are rebounding in developed countries after being firmly in retreat for decades. The consequences can be devastating. Syphilis, for example, causes more than 200,000 stillbirths and infant deaths worldwide annually, and years later can lead to blindness, dementia or paralysis. The resurgence is a result of multiple factors including inconsistent condom usage and the abuse of illicit recreational drugs. At the same time, some common STIs, such as gonorrhea and shigellosis, are becoming harder to treat due to antibiotic resistance. In the U.S., which has the highest rates of sexually transmitted disease in the developed world, the crisis is costing an estimated $16 billion annually in preventable health-care expenses.

How bad is the problem?

In the U.S., cases of chlamydia, gonorrhea, and syphilis — three of the most common, treatable sexually transmitted diseases — jumped by more than 200,000 in 2017 to almost 2.3 million, a record. With syphilis, the annual rate of reported cases in the U.S. has almost doubled in recent years, to 31.4 cases per 100,000 people in 2017 from 15.9 per 100,000 in 2012. The trend with syphilis has also been seen in such countries as France, Belgium, Ireland and the U.K. In Australia, reported cases of gonorrhea climbed 63 percent from 2012 to 2016, while they surged sixfold in France and almost fivefold in Denmark from 2007 to 2016.

What’s driving that rise?

It’s complicated. Take syphilis: While the bulk of the roughly 6 million cases occurring annually are in low- and middle-income countries, some of the largest annual increases are in high-income countries. In these countries, syphilis has spread from some high-risk groups, such as gay and bisexual men, to the wider community. In the U.S., rates of early-stage syphilis among women surged 156 percent from 2013 to 2017. The Centers for Disease Control and Prevention says that’s associated with a corresponding rise in sexualized drug use — using methamphetamines or injection drugs, including heroin, to facilitate unprotected sex with multiple partners. Similarly in Europe, such practices, known as “party and play (PnP),” “chemsex” or “slamming,” have been shown to spur sex work and risky behavior, especially among men who have sex with men.

Are there other factors?

Yes. In the U.S., for example, the decline in AIDS mortality since the mid-1990s has been associated with a rebound in syphilis cases among men who have sex with men. More recently, the introduction of drugs to prevent HIV transmission — called pre-exposure prophylaxis, or PrEP — has shown great promise in reducing new infections among these men. It’s also been associated with less consistent use of condoms — one of the best means of protection against other STIs. More routine STI screening tests among PrEP users has made it difficult to know whether previously unrecognized and untreated infections are now being diagnosed or if there has been an actual increase. More international travel and labor migration also mean that germs are spreading faster and wider.

What are the consequences?

Each infectious agent presents its own particular dangers. For example, up to 40 percent of pregnancies with untreated syphilis result in miscarriage, stillbirth or early infant death. The surviving babies may suffer from abnormalities including skeletal defects, hearing impairment and meningitis, which can cause developmental delays and seizures. Reported cases of syphilis passed from a mother to her baby have more than doubled in the U.S. since 2013, reaching a 20-year high of 918 in 2017. Florida, California, Arizona, Texas and Louisiana accounted for 70 percent of cases. With chlamydia, 80 percent of infections are asymptomatic, yet even then it can be spread via sex. The infection is particularly serious for women. If untreated it may move to the upper reproductive tract, resulting in pelvic inflammatory disease. That can lead to ectopic pregnancy, chronic pain and infertility. Newborns may get pneumonia if they are infected in the uterus. Men with untreated chlamydia may develop arthritis.

How serious is drug-resistant gonorrhea?

Very. The bacterium has evolved to thwart multiple antibiotics, leading to four reported cases of extensively drug-resistant disease in the U.K. and two in Australia. While the bacterium is broadly susceptible to some newer antibiotics, these appear to be less effective at clearing the infection from the throat. Germs in the throat can spread surreptitiously via kissing, making them harder to stop. A key concern is that ceftriaxone, a backbone of treatment globally, is losing its potency, hastening the threat of untreatable gonorrhea. When the disease isn’t treated, it can cause infertility in both women and men, and potentially lead to a lethal bloodstream infection.

What can be done?

Experience has shown that encouraging condom use isn’t sufficient to curb infections. New tools and therapeutic agents, such as antiviral and antibiotic drugs, are needed. Vaccines, which have significantly reduced cases of human papillomavirus (HPV) and hepatitis B cases, could be an important defense. Research into vaccines against herpes and HIV is advanced, while those for chlamydia, gonorrhea, syphilis and trichomoniasis, another common STI, are in earlier stages of development.

What about the rest of the world?

Most of the more than 1 million people who catch a sexually transmitted infection each day are in low- and middle-income countries. Broadly, STIs are a barometer of access to health care: The worst rates occur in groups least likely to be tested and treated. The World Health Organization recognizes female sex workers, people who inject drugs, men who have sex with men, and transgender women as being most vulnerable. Faster and more-reliable testing at the point of care would make it easier to detect and treat infections earlier, especially in developing countries and remote areas.