Jacob Kushner: 一人两颗小药丸,中国准备把非洲的疟疾给灭了|2019-07-10

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《大西洋月刊》7月4日刊登《中国的刚果计划》一书作者雅各布·库什纳文章《中国正在领导非洲下一步抗疟行动》 文:Jacob Kushner 译:范莉 2007年,比尔及梅琳达·盖茨基金会宣布它将

《大西洋月刊》7月4日刊登《中国的刚果计划》一书作者雅各布·库什纳文章《中国正在领导非洲下一步抗疟行动》

文:Jacob Kushner

译:范莉

2007年,比尔及梅琳达·盖茨基金会宣布它将致力于在全球范围内消灭疟疾。不过,当它迈出这一步的时候已经比较晚了。

正是在那一年,中国科学家们与慈善家朱拉伊的新南方集团合作,已经开始在非洲小国科摩罗消灭当地的疟疾。现在他们满怀壮志地把目光投向一个更大的区域:肯尼亚,一个人口将近5000万的东非国家。

中国-科摩罗复方青蒿素快速清除疟疾项目团队合影

当媒体还在频频关注西方捐助者为昂贵的、实验性的疟疾干预措施筹集资金时,中国的研究人员已经在采取一种经过较完整测试的抗疟手段。这就是群体药物配给(mass drug administration,简写为MDA),即同时向给定区域里的所有人提供抗疟疾药丸。中国人认为,与其在全世界消灭通过血液传播疾病的蚊子,为什么不直接消灭人群中的疟疾呢?

如果这一努力获得成功,它将大大减轻疟疾给肯尼亚卫生系统和经济造成的负担,同时也将向世界展示中国在非洲的善行,甚至可能有助于改变当地人认为中国制造的商品药品质量低劣的观念。不久前,中国超过了美国成为非洲最大的贸易伙伴,其在非洲的年投资总额也在过去15年里从5亿美元翻了60倍达到了320亿,中国与非洲的科学和公共卫生部门的合作将向世界表明,中国向非洲提供的远不止于道路、火车和货物。

中国国内至少从1981年就开始就采用群体药物干预与其它办法相结合的方式对抗疟疾;去年,中国本土没有发现新增疟疾病例,这可能数千年来的第一次。但是群体药物干预在科学和伦理方面不乏争议。有人担心它将导致抗药性不断提高,使疟疾病发率陡增到几十年来未见的水平。还有人认为把抗疟药物给没有感染的人或者不希望服药的人是有悖伦理的,尽管肯尼亚等国的当地人并不理会这种顾虑。美国的政策制定者也面临类似的困境,他们在讨论如何回应正在兴起的反疫苗运动。中国的官员、研究人员和慈善家似乎并没有这方面的担忧,肯尼亚的官员也是如此。

伯恩哈兹·奥古图(Bernhards Ogutu)医生数十年如一日地在肯尼亚医学研究所研究疟疾,他赞同中国的抗疟方式。他告诉我,长期以来世界抗疟工作“基本上就是在灭火”:等到人们已经得了病再治疗他们。他预计,如果在肯尼亚部分地区采用群体药物干预以及其他类似手段,“我们可以在未来五年内彻底消灭疟疾。”

疟疾传播途径

疟疾是一种使人虚弱的疾病,可以让强壮健康的成年人卧病在床长达数周,也是撒哈拉沙漠以南非洲地区儿童夭折的三大主要原因之一。得病的症状包括发烧、发冷、颤抖、肌肉疼痛和严重疲劳。

世界卫生组织称,全球几乎一半人口有得疟疾的风险。每年有2.12亿人受到疟疾折磨,其中有43万人病故——也就是说每天有将近1200人因此死亡。非洲的疟疾病例占全世界的90%,因病死亡人数占全球的92%。

宋健平是广州中医药大学热带医学研究所副所长,该机构的群体药物干预研究获得了中国政府资助,他表示非洲的疟疾病例和死亡人数都有大幅减少的可能。他说:“问题不是我们没有药,也不是没有治疗办法。问题还是出在观念上。”宋健平认为光靠预防是不足以对抗疟疾的,他补充道:“如果非洲可以全面推行群体药物干预,10年内疟疾将不复存在。”

彻底根除疾病不是件容易的事:迄今为止人类只成功从地球上消灭了两种疾病,天花和牛瘟。为非政府组织“国际人口服务”的疟疾项目工作了20年的德斯蒙·沙瓦斯(Desmond Chavasse)表示:“群体药物配给是非常有争议的干预手段。”但是它的好处在于一劳永逸。

中国不是最近才加入全球抗疟之战的。1972年,中国科学家屠呦呦发现了抗疟疾化合物青蒿素,并研究出从青蒿类植物中提取青蒿素的方法,最终于2015年获得了诺贝尔奖。在过去至少2000年里,蒿都被用来治疗发热和其它与疟疾相符的症状。

中国科学家屠呦呦发现了抗疟疾化合物青蒿素,并找到了它的提取方法。青蒿素是中国援非抗疟工作的关键。

如今,青蒿素是世界上疗效最好、应用最广的抗疟化合物,每年有数百万剂青蒿素复方药物(artemisinin combination therapies ,简称ACT)问世。一些帮助研制青蒿素复方药物的中国科学家现在将注意力转移到非洲的群体药物干预上。中国新南方集团总裁朱拉伊说,他个人已经在非洲的群体药物干预研究和实验上投入了3亿美元,并且公司正在和肯尼亚卫生部门协商,在该国港口城市蒙巴萨附近长期受疟疾困扰的沿海地区对10000人试行群体药物干预。

但是与岛国科摩罗的情况不同,许多肯尼亚内陆居民经常往来于沿海地区,这就造成一个问题:有些人在配给药物的时候出城了,回来时血液里带着疟原虫,又把疟疾带回了当地。也有人担心群体药物干预会导致疟原虫产生抗药性。但宋健平说:“如果我们配给的剂量得当,行动迅速,就可以抢在抗药性产生之前消灭疟原虫。

抗药性已经威胁到了上一项伟大的抗疟疾技术——蚊帐——所取得的成就。在1990年代,经杀虫剂处理的蚊帐带来一个突破,使世界范围内疟疾发病率稳步下降。沙瓦斯说,目前的问题在于“我们已经得到了蚊帐可能带来的大部分好处。科学家指出,如果没有新的杀虫剂、药物和治疗手段,我们很快就会看到全世界疟疾发病率再次增长。许多慈善家和投资人不愿意投资群体药物干预,因为老办法的成效是经过实践检验的。“但是像现在这样抵抗疟疾,只会让我们一直病着”,奥古图说道。

在坦桑尼亚一间纺织厂里,工作人员在检查经杀虫剂处理的蚊帐是否有破洞

肯尼亚政府数据显示,该国70%的人口有感染疟疾的风险,疟疾带来的破坏性远大于疾病本身。“患疟疾的人没法工作。生产力下降了。如果患病的是儿童,就没法去上学了,”肯尼亚国家疟疾控制计划的瑞贝卡·吉普图伊(Rebecca Kiptui)说,“如果大家都病了,肯尼亚的经济就遭殃了。”五年前,肯尼亚37%的门诊是治疟疾的。研究疟疾对该地区经济影响的学者表示,肯尼亚每年因病旷工的损失和治疗疟疾的费用加起来达到1.09亿美元。

有些人担心中国的新南方集团是想要分一杯羹,通过推广MDA来提高它自己药品的销量。青蒿科技是新南方集团旗下众多控股公司之一,2006年这家制药公司的科学家发明了复方青蒿素抗疟药“粤特快”(Artequick),它于2009年被中国卫生部列为防治恶性疟疾的首选药物。2010年,它被中国商务部列为出口非洲的首选抗疟药品。但是沙瓦斯说:“这里存在着根本性的利益冲突,为什么一家中国的青蒿素复方药生产商会去研究群体药物干预?要不要采用群体药物干预应当由研究疟疾的学者说了算,而不是制药公司。”

宋健平介绍,患者只需在患病24小时内服用两次“粤特快”即可,疗程短、费用低,毒副作用小,适合在非洲推广

但奥古图对这种观点不屑一顾,他认为中国这样做的背后没有什么不可告人的动机。他说:“我们生活在阴谋论中,仿佛什么事背后都有一些隐秘的计划。”在新南方集团的案例中,前面提到的担心似乎有些牵强:抗疟药不像抗生素和专用药物,它几乎不赚钱,青蒿素类抗疟药一片仅售几分钱。

新南方集团抗疟行动迫使我们考虑一种可能性,那就是像朱拉伊这样的中国亿万富翁可能真的是大公无私的,就像已经投入20亿美元对抗疟疾的比尔盖茨夫妇等西方慈善家一样,驱使他们的都是利他主义。如果非要说两者有什么不同,那就是新南方集团还有一部分动力来自民族自豪感。上个月,曾参与尼日利亚群体药物干预项目的彭喜亮在他位于肯尼亚首都内罗毕的办公室中对我说:“我们想把中医药推向全球。”

许多西方人和非洲人对中医药的热情并不高。在中国参与非洲事务这件事上,有种流行的观点认为中国制造是有缺陷的、便宜的、劣质的,甚至是假冒的。新南方集团的抗疟行动也遭到了类似的指责。2014年,美国哥伦比亚广播公司新闻网在报道中对新南方集团的新药“粤特快”提出了质疑,尽管构成这种复方药的三种药物成分都经过了充分的研究,在全球防治疟疾行动中广为应用,并且被研究人员认为是治疗疟疾的有效方法。

2014年CBS关于中国在科摩罗抗疟的报道,文章称人们需要“数月乃至数年,才能相信中国找到了真实、安全、持久的方法来治疗这个致命疾病。”

围绕此事的争议和科学关系不大,主要是意识形态的分歧:消灭疟疾乃至医疗卫生事业究竟是社会事务,还是个人事务?

部分美国家长不给孩子接种麻疹疫苗,毫无来由地担心疫苗会导致自闭症,我的一些中国和肯尼亚的朋友都对此感到非常震惊,并质疑接种疫苗为什么不是强制性的。在把卫生视为公益而非个人权利的社会中,那种认为哪怕反科学甚至引发公共卫生紧急事件也必须尊重个人自由的观念显得很荒谬。

而且,批评中国的人还忽略了一个现实,在非洲许多地方,通过科学解决问题已经变成了一种协作事务。2018年11月,中国科学院在内罗毕附近开设了首个中-非联合研究中心。中国和肯尼亚的科学家合作研究抗旱农作物,提高水稻产量,研发锁水新技术改良土壤使其适合玉米种植。

中国的药物为肯尼亚带来了福音:这里的药店货架上既有中国制造的青蒿素,也有瑞士诺华制药公司的全球知名产品。自2003年以来,中国向肯尼亚政府捐赠了抗疟疾和抗艾滋病药物。吉普图伊表示,她欢迎“任何符合我们需求的抗疟合作伙伴”,无论他们来自“美国、中国、泰国,还是任何地方。”

“在公共卫生领域,”吉普图伊说,“你要为最多的人做最多的好事。”

“人们需要一点时间来理解,”彭喜亮告诉我,不过“在非洲越来越多的人开始认识到中医药的好处。”

China Is Leading the Next Step in Fighting Malaria in Africa

In 2007, the Bill & Melinda Gates Foundation said it was committed to eradicating malaria across the globe. By then, it was late to the game.

That year, Chinese scientists working with a Chinese philanthropist and his company, New South, had already begun eradicating malaria from the small African nation of Comoros. Now they’re setting their sights on a more ambitious location: Kenya, the East African nation of nearly 50 million people.

As Western donors garner headlines for funding expensive, experimental malaria interventions, Chinese researchers are undertaking a far more tested approach. Called mass drug administration, or MDA, it involves giving antimalarial pills to every man, woman, and child in a given area all at once. Rather than kill off the world’s mosquitoes, which spread the disease by drawing blood from infected people, the thinking goes, why not simply wipe out malaria among humans?

If successful, the effort would ease the disease’s burden on Kenya’s health system and economy. But it would also showcase Chinese philanthropy in Africa, and may even help change the perception here that Chinese-made goods and medicine are of poor quality. Having recently surpassed the United States to become Africa’s leading trade partner, and with Chinese investment in Africa rising sixtyfold from $500 million to $32 billion in the last 15 years, Chinese cooperation in the continent’s science and public-health sectors may show the world that the country has far more to offer Africa than just roads, railways, and things.

China has employed MDA, along with other methods to fight malaria, at home since at least 1981; last year, for the first time in what is likely millennia, it saw no new native cases of the disease. But MDA is controversial for reasons of both science and ethics. There are concerns that it could lead to increased drug resistance, which could see malaria rise to levels not seen in decades. Others believe it’s unethical to give antimalarials to people who may not even have the disease—or who don’t wish to take them—though such qualms are dismissed in Kenya and elsewhere. Similar dilemmas are challenging U.S. policy makers as they debate how to respond to the rising anti-vax movement.

Chinese officials, researchers, and philanthropists seem unworried by these concerns—as are some Kenyan officials.

Dr. Bernhards Ogutu, who has spent decades studying malaria for the Kenya Medical Research Institute, welcomes the Chinese. For too long, he told me, the world has been “basically firefighting”: waiting until people become sick with the disease, then treating them. He predicted that by using MDA and similar methods, in some parts of Kenya, “we can totally eradicate malaria in the next five years.”

Malaria is a debilitating sickness that can make strong, healthy adults bedridden for weeks and is one of the three leading causes of death for children in sub-Saharan Africa. Symptoms include fever, chills, shaking, muscle aches, and severe fatigue.

According to the World Health Organization, almost half the global populationis at risk for malaria. Each year the disease afflicts 212 million people and kills 430,000 of them—nearly 1,200 deaths each day. Ninety percent of malaria cases and 92 percent of deaths occur in Africa.

Song Jianping, deputy director of the Institute of Tropical Medicine at Guangzhou University, which receives funding for its MDA research from the Chinese government, says those numbers could be drastically lowered. “It is not like we don’t have the medicine. It’s not like we don’t have the methods. The hurdle is the wrong perception,” he says. Fighting malaria through prevention is not enough, Song adds. “If the whole [of] Africa can run MDA, in 10 years, there will be no malaria.”

Eradicating the disease won’t be easy: Humans have only succeeded in wiping two diseases—smallpox and rinderpest—from the face of the Earth. “Mass drug administration—that’s a very controversial intervention,” says Desmond Chavasse, who for two decades has worked on malaria initiatives for the NGO Population Services International (PSI). But the appeal “is that the result is there for generations.”

China isn’t new to the global fight against malaria. Chinese scientist Tu Youyou discovered the antimalarial compound artemisinin, in 1972, and figured out how to extract it from the Asian sweet wormwood plant, eventually earning her the Nobel Prize in 2015. For at least 2,000 years, wormwood was used to treat fevers and other symptoms consistent with what we now know to be malaria.

Today, artemisinin is the most effective and widely used antimalarial compound in the world, with millions of doses of artemisinin combination therapies (ACTs) given out each year. Some of the Chinese scientists who helped develop ACTs are now shifting their attention to using MDA in Africa. New South, the Chinese company whose CEO, Zhu Layi, says he has personally spent $300 million on MDA research and experiments in Africa, and his company is in talks with Kenyan health officials to do an MDA test run among 10,000 people on the country’s Indian Ocean coast, near the port city of Mombasa, where malaria is endemic.

But unlike those living in Comoros, many on the Kenyan mainland regularly travel or commute around the region, which poses a problem: People who are out of town when the drugs are administered might return carrying the parasite in their blood, reintroducing malaria to the area. There is also concern that the MDA approach could result in the malarial parasite building up resistance to the drugs used in the treatment. But, says Song: “If we can manage to give the correct dose, and do it fast, then we can kill the parasites before they develop resistance.”

Already, resistance is threatening to undermine the gains made by the last great antimalarial technology: bed nets. In the 1990s, the advent of the insecticide-treated mosquito net led to a breakthrough that resulted in a steady decline of malaria around the world. The problem is that “we’ve already harvested most of the benefits you can expect to harvest” from nets, Chavasse says. Without new insecticides, drugs, and treatment methods, scientists say we’ll soon see an increase in malaria worldwide. Many donors and investors are hesitant to invest in approaches like MDA when older methods have worked in the past. “But the current way of doing this is just going to keep us sick,” Ogutu said.

In Kenya, where 70 percent of the population is at risk for malaria, according to government data, the devastation of the disease goes beyond the sickness itself. “People who get malaria are not able to go to work. Your productivity goes down. If you’re a child, you will not be able to go to school,” says Rebecca Kiptui, of Kenya’s National Malaria Control Program. “If everybody falls sick, then the Kenyan economy would suffer.” Five years ago, 37 percent of all outpatient treatments given in Kenya were for malaria. Taken together, lost work hours and the cost of treating patients for malaria amount to $109 million a year, according to researchers who studied the economic effects of the disease in the region.

Some worry New South, the Chinese company, may be trying to get a piece of the pie—that its MDA campaign may in fact be a ploy to increase sales of its own medicine. Among New South’s vast holdings is a pharmaceutical wing whose Chinese scientists in 2006 invented Artequick, an ACT that China's Ministry of Health approved as the "drug of choice" for treating malaria in the country in 2009. The next year, Beijing listed Artequick as the preferred malaria drug for export to Africa. But Chavasse says “there is a fundamental conflict of interest for why a Chinese ACT manufacturer would be carrying out a research project on mass drug administration.The thought needs to be driven by malaria academics—not by drug companies.”

But Ogutu dismissed the idea that Chinese endeavors must have some ulterior motive. “We live in a conspiracy—that there’s some hidden agenda,” he said. In New South’s case, those fears seem misplaced: Unlike antibiotics and more specialized drugs, there is little money to be made from malaria treatment, with artemisinin-based malaria meds selling for just pennies per pill.

Rather, the company’s campaign to eradicate malaria forces us to reckon with the possibility that Chinese billionaires such as Zhu might be driven by the same altruistic intentions that drive their Western counterparts—philanthropists such as Bill and Melinda Gates, who have spent more than $2 billion fighting malaria. If anything, New South’s secondary motivation isn’t only profit, but also pride. “We want to promote Chinese medicine to the globe,” Ethan Peng, who worked on New South’s MDA efforts in Nigeria, told me last month from his office in Nairobi, Kenya’s capital city.

Many in the West and in Africa are not enthused. Amid popular narratives about Chinese engagement in Africa is the assumption that Chinese-made products are faulty, cheap, subpar, or fake. Similar accusations have been directed at New South’s malaria-eradication campaign. A 2014 report by CBS News questioned the use of New South’s new drug, Artequick, even though it’s a combination of three drugs that are well studied, widely used to fight malaria globally, and deemed by researchers to be an effective treatment for malaria.

The real debate may have less to do with science than it does with ideology: Is malaria elimination—or for that matter, health care in general—a societal affair, or an individual one?

Several of my Chinese and Kenyan friends alike are astounded that some American parents refuse to vaccinate their children against measles out of a disproven fear of autism, and question why people even have that choice. The notion that individual liberties should be respected even when they refute science—to the point of creating a public-health emergency—seems ludicrous in societies where health is treated not as an individual right, but as a common good.

Moreover, such criticism ignores the reality that, in many parts of Africa, solving problems through science has already become a collaborative affair. In November, the Chinese Academy of Sciences opened its first-ever research center in Africa, near Nairobi. Chinese and Kenyan scientists work together to create drought-resistant crops, increase rice yields, and develop new methods for trapping water in the ground to better grow maize.

Chinese medicine has been a boon to Kenya: Pharmacies here carry Chinese-manufactured artemisinin alongside more globally recognized products from the Swiss pharma corporation Novartis, and since 2003 China has donated malaria and HIV drugs to Kenya’s government. Kiptui says she welcomes “any partner in malaria as long as they line up with our needs,” be they from “America or China or Thailand, or wherever.”

“In public health,” Kiptui says, “you do the greatest amount of good for the greatest amount of people.”

“It takes some time for people to understand,” Peng told me. But “in Africa, more and more people are getting to recognize that Chinese medicine is very good.”

(End)

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