邁向消除愛滋病毒垂直傳播的途徑
資料來源：刺胳針愛滋病毒期刊；財團法人台灣紅絲帶基金會編譯
2021 年 11 月 26 日，世衛組織發布了關於消除 HIV、梅毒和B型肝炎病毒母嬰傳播的驗證標準和程序之第三版全球指南。該文件是支持努力以減少並終結 HIV 垂直傳播（也稱為母嬰傳播）的重要工具，這是實現免除愛滋世代的重要一步。這是整合並納入消除B型肝炎病毒指引和指標的第一版，它包括一個新機制，以表彰這些高負擔國家在消除垂直傳播的道路上採取重要的步驟：愛滋病毒高負擔國家在終止垂直傳播方面取得了實質性進展的國家可以申請銅牌、銀牌、金牌等級狀態。非洲的波札那是一個愛滋病普遍流行、感染負擔高的國家，已成為非洲第一個成功申請銀牌級身份的國家，波札那的成就令人樂觀。
自古巴於 2015 年獲得消除愛滋病毒垂直傳播的驗證後，泰國、白俄羅斯、亞美尼亞、安吉拉、蒙塞拉特、開曼群島、百慕達、安提瓜和巴布達、聖克里斯多福及尼維斯、馬來西亞、馬爾地夫、斯里蘭卡和多明尼加（按時間順序）均達成相同成就。但對於愛滋病毒負擔最重的東非和南部非洲國家，以及其他愛滋病毒普遍流行和育齡婦女愛滋病毒流行率高的國家來說，這一里程碑式的目標更難實現。這些國家要達到消除的目標需要攀登更高的山峰，因此他們的努力和成功可能會被忽視。各國現在可以在達到明確定義的目標時向世衛組織申請認可：母乳喂養人口中愛滋病毒垂直傳播率低於 5% ，以及每 100,000 名活產中透過垂直感染愛滋病毒之新發兒科感染病例數少於或等於 750個案率且產前保健覆蓋率、孕婦 HIV 檢測和 HIV 感染孕婦的抗反轉錄病毒治療 (ART) 覆蓋率至少達到 90%的國家授予銅牌；銀牌級要求相同的成就，但透過垂直感染的兒童新發HIV 感染病例率為每 10 萬活產 500 例或更少；黃金等級則要求每 10 萬活產的病例率低於或等於 250 例，以及孕婦產前護理、愛滋病毒檢測和抗反轉錄病毒治療的覆蓋率達到 95%。
儘管育齡婦女的愛滋病毒負擔很高，波札那的獎項是對其阻止愛滋病毒垂直傳播努力的認可。聯合國愛滋病規劃署數據顯示，在2020 年，100% 的孕婦接受抗逆轉錄病毒治療，遠高於 2010 年的 76%，垂直傳播率僅為 1.6%，亦遠低於當時的 9.2%。許多其他國家正在取得顯著進展，並可能申請認可其在消除道徑路上的步驟。聯合國愛滋病規劃署的數據顯示，馬拉威和莫三比克（僅選擇兩個國家）已將抗反轉錄病毒療法擴大到所有愛滋病毒陽性的孕婦，並且由於治療擴大以及其他各項的努力，垂直傳播率已經下降。
世衛組織新指南的一個關鍵成分是，提供按步就班的指導婦女實質的參與，以確保人權、性別平等和社區參與等均能良好地彙整到指導和驗證中。這一舉措更體現在對正處在消除階段上之愛滋感染婦女其對產前保健、愛滋病毒檢測以及治療的需求上。在 1 月，南部非洲愛滋病毒司法網絡和愛滋病權利聯盟對於感染愛滋病毒的婦女正面臨將母乳哺喂養視為犯罪——將 HIV 定為犯罪不符合全球目標，在預防垂直感染止亦是如此。愛滋病毒司法網絡亦為協助面臨法律究責的愛滋感染婦女的律師們製作了一個母乳哺喂之辯護工具包。
在華盛頓特區舉行的 2012 年愛滋病大會十年後，當人們接受了免除滋世代的呼籲時，看到在減少垂直傳播方面取得的這些成就令人振奮，而且這些成就植根於產前保健、愛滋感染婦女公平地獲得保健和人權。越來越多的國家和地區通過消除驗證和消除路徑里程碑的認證是審慎樂觀的原因。只有持續在阻斷垂直傳播方面取得成功，才能實現沒有愛滋的世代，為此，對產前保健、愛滋病毒檢測和嬰兒早期診斷的持續支持至關重要。 ■ 刺胳針愛滋病毒期刊
The path to elimination of vertical transmission of HIV
On Nov 26, 2021, WHO published the third edition of Global guidance on criteria and processes for validation: elimination of mother-to-child transmission of HIV, syphilis and hepatitis B virus. The document is an important tool to support efforts to reduce and eventually end vertical transmission of HIV (also known as mother-to-child transmission)—an essential step in achieving an AIDSfree generation. This is the first edition to incorporate guidance and metrics for elimination of hepatitis B virus, and it includes a new mechanism to recognise highburden countries that have made important steps on the path to elimination of vertical transmission of these infections: the bronze, silver, and gold tier statuses can be applied for by countries with high burdens of HIV that have made substantial headway in efforts to end vertical transmission. Botswana, a country with a generalised HIV epidemic and a high burden of infection, has become the first country in Africa to apply successfully for silver-tier status. Botswana’s achievement is a cause for optimism.
Since Cuba received validation for elimination of vertical transmission of HIV in 2015, Thailand, Belarus, Armenia, Anguilla, Montserrat, Cayman Islands, Bermuda, Antigua and Barbuda, St Kitts and Nevis, Malaysia, Maldives, Sri Lanka, and Dominica have all made (in that chronological order) the same
achievement. But the landmark is harder to reach for the countries with the highest HIV burdens in east and southern Africa, and other countries with generalised HIV epidemics and high prevalences of HIV in women of childbearing age. Such countries have a much higher mountain to climb to reach elimination, and so their efforts and successes may go unheralded. Countries can now apply to WHO for recognition when they have reached clearly defined goals: bronze tier is awarded for countries with vertical HIV transmission rates of less than 5% in breastfeeding populations, and a case rate of new paediatric HIV infections through vertical transmission of 750 cases per 100,000 live births or less, with at least 90% coverage of antenatal care coverage, HIV testing in pregnant women, and antiretroviral therapy (ART) coverage in pregnant women living with HIV; silver tier requires the same achievements but a case rate of new paediatric HIV infections through vertical transmission of 500 per 100,000 live births or less; gold tier requires a case rate of fewer than 250 per 100,000 live births or less and 95% coverage of antenatal care, HIV testing, and antiretroviral therapy.
Botswana’s award is in recognition of efforts to stop vertical transmission of HIV despite the high HIV burden in women of childbearing age. UNAIDS data show that, in 2020, 100% of pregnant women were receiving ART, up from 76% in 2010, and vertical transmission rates were just 1·6%, down from 9·2%. Numerous other countries are making remarkable progress and are likely to apply for recognition of their steps on the path to elimination. UNAIDS data show that Malawi and Mozambique (to pick just two countries) have expanded access to ART to all pregnant women living with HIV, and vertical transmission rates have tumbled as a result of treatment expansion and other efforts.
A key component of the new WHO guidance is provision of step-by-step guidance on meaningful
engagement of women to ensure that human rights, gender equality, and community engagement are well
integrated into guidance and validation. This move is reflected in the requirements for antenatal care, HIV
testing, and treatment for women living with HIV in the path-to-elimination tiers. In January, the HIV Justice
Network and AIDS Rights Alliance for Southern Africa raised concerns that women with HIV are being
criminalised for breastfeeding—criminalisation of HIV is incompatible with global goals and this is no less true in respect to prevention of vertical transmission. The HIV Justice Network have produced a Breastfeeding Defence Toolkit for lawyers working with women with HIV who face legal censure.
A decade on from the AIDS 2012 conference in Washington DC, when the call for an AIDS-free generation was embraced, it is heartening to see such achievements in reducing vertical transmission, and that those achievements are rooted in antenatal care, equitable access to care for women with HIV, and human rights. Increasing numbers of countries and territories with validation of elimination and certification of path-to-elimination milestones are reasons for cautious optimism. An AIDS-free generation will only be achieved with ongoing successes in blocking vertical transmission, for which, ongoing support for antenatal care, HIV testing, and early infant diagnosis are essential. ■ The Lancet HIV