在英國男同性戀者的愛滋病毒發生率於短短兩年內下降了55％
資料來源：Roger Pebody,aidsmap news; 發佈時間：2019年3月5日；財團法人台灣紅絲帶基金會編譯
Dana Ogaz於2019年反轉錄病毒和伺機性感染會議（CROI 2019）演講中的圖表
今天在西雅圖，來自英國公共衛生部的Dana Ogaz於2019年反轉錄病毒和伺機性感染會議（CROI 2019）的演講中，其所提供的數據顯示，在短短兩年內，於英國進入性健康診所就診的男男間性行為者當中，其愛滋新感的發生率下降了55％。
模型的研究在之前即曾顯示，自2012年以來，發生率開始下降，而新診斷的報告人數自2014年以來一直在下降。今天所提供的數據，來自於同一年內曾兩次或多次在同一性健康診所就診的男同性戀、雙性戀以及其他男男間性行為者（MSM）的常規數據。在任何的一年當中，這些人約佔使用診所之男男間性行為者的三分之一。然而，他們可能無法代表更廣泛的整個男男間性行為者群體。
發生率在2012 – 2013年量測，然後再於2014 – 2015年和2016 – 2017年的再次測量。在第一年，發生率為1.9％（意味著每年100名男性中有2人獲得艾滋病毒），在第二個時期保持穩定在1.8％；但僅僅兩年後，發生率僅為0.8％。
在MSM中也看到了類似的模式，他們在過去的一年中都進行過愛滋病病毒檢測陰性和有細菌性性傳染病感染 – 這是一個愛滋病毒感染風險較高的群體。發生率從3.7％下降到3.4％再下降到1.6％（過去兩年下降53％）。
在此期間，性傳染病的診斷則一直在上升。在2012年至2017年期間，在進入性健康診所的男同性戀者中，淋病診斷增加了90％，衣原體診斷增加了80％，梅毒診斷增加了160％。
在2017年，12.1％的男同性戀男性患有淋病（三分之一為直腸感染），9.0％衣原體感染（一半為直腸感染），2.7％患有梅毒。
愛滋病毒新感診斷的下降恰逢越來越多的男性接觸到暴露前預防投藥（PrEP），而改善檢測並迅速啟動愛滋病之治療亦同時持續地努力中。
Ogaz說英國公共衛生部門進行了這項活動，以便該國在推出暴露前預防投藥（PrEP）時能提供監測感染的基準線。她說，隨著情況的發展，解開暴露前預防投藥對於已經下降的HIV發生率和性傳染病診斷增加的貢獻則需要仔細地考慮。
55% drop in HIV incidence in gay men in England in just two years
Graph from Dana Ogaz’s presentation at CROI 2019., Roger Pebody; Published: 05 March 2019
In just two years, the incidence of new HIV infections in men who have sex with men attending English sexual health clinics fell by 55%, according to data presented by Dana Ogaz of Public Health England at the Conference on Retroviruses and Opportunistic Infections (CROI 2019) in Seattle today.
Modelling studies have previously suggested that incidence began to fall in 2012 and reports of new diagnoses have been falling since 2014. The figures presented today come from routinely collected data from gay, bisexual and other men who have sex with men (MSM) who attend the same sexual health clinic twice or more in the same year. In any given year, this is around a third of the MSM who use the clinic. However, they may not be representative of the wider population of MSM.
Incidence was measured in 2012-2013, then in 2014-2015, and again in 2016-2017. In the first year, incidence was 1.9% (meaning that two in every 100 men acquired HIV during the year), remaining stable at 1.8% in the second time period. But just two years later, incidence was only 0.8%.
A similar pattern was seen in MSM who had both had an HIV-negative test and a bacterial STI in the past year – a group at higher risk of HIV infection. Incidence fell from 3.7% to 3.4% and then to 1.6% (a 53% fall in the last two years).
Over this time period, diagnoses of sexually transmitted infections have been rising. Between 2012 and 2017, there was a 90% increase in gonorrhoea diagnoses, 80% increase in chlamydia diagnoses and 160% increase in syphilis diagnoses among gay men attending sexual health clinics.
In 2017, 12.1% of gay men attending clinics had gonorrhoea (a third had a rectal infection), 9.0% chlamydia (half had a rectal infection) and 2.7% had syphilis.
The fall in HIV diagnoses coincides with a period when increasing numbers of men accessed pre-exposure prophylaxis (PrEP), while efforts to improve testing and prompt initiation of HIV treatment continued.
Ogaz said Public Health England conducted the exercise in order to provide a baseline for monitoring infections as the country rolls out PrEP. She said that as the situation evolves, untangling the contribution of PrEP to already falling HIV incidence and increases in STI diagnoses will require careful consideration.
Reference
Ogaz D et al. Preparing for PrEP in England: prevalence and incidence of HIV and bacterial STIs.Conference on Retroviruses and Opportunistic Infections, Seattle, abstract 48, 2019.