布基纳法索，加姆佩拉——在布基纳法索的一个小诊所里，链条断裂了，那里几乎一年都没有可用的冰箱。
结果是:世界各地受病毒大流行影响最严重的穷人也可能是最后一个从中恢复的人。
疫苗冷链障碍只是这种流行病对穷人造成的最新不平等，穷人更经常在允许病毒传播的拥挤条件下生活和工作，很少获得对新冠肺炎治疗至关重要的医用氧气，他们的健康系统缺乏实验室、供应品或技术人员来进行大规模测试。
维持冠状病毒的冷链疫苗即使在最富裕的国家，这也不容易，尤其是那些需要零下70摄氏度(零下94华氏度)的超低温的国家。对基础设施和冷却技术的投资落后于疫苗开发今年因病毒而取得的高速增长。
随着大流行进入第八个月，物流专家警告说，世界上大多数地方缺乏冷藏来管理有效的疫苗接种计划。这包括中亚的大部分地区，印度和东南亚的大部分地区，除了最大的国家之外的拉丁美洲，以及除了非洲的一小部分以外的所有地区。
布基纳法索首都郊外的医疗诊所是一个障碍的缩影，这座布满灰尘的建筑为11000人服务。
去年秋天冰箱坏掉后，诊所再也无法保存疫苗护士Julienne Zoungrana说，在现场预防破伤风、黄热病、肺结核和其他常见疾病。取而代之的是，工作人员使用摩托车从瓦加杜古的一家医院用隔热的运输工具运送小瓶，在一条狭窄的道路上往返行驶40分钟，道路上有泥土、砾石和人行道。
一位参观甘珀拉诊所的两个孩子的母亲说，她认为冠状病毒接种计划在她所在的地区将是一项挑战。24岁的阿达玛·塔普索巴(Adama Tapsoba)在烈日下走了四个小时，为她的孩子进行例行免疫接种，她经常要等几个小时才能看到医生。一周前，她5个月大的儿子错过了一次预定的注射，因为塔普索巴的女儿生病了，她只能带一个孩子走路。
“很难接种(COIVD-19)疫苗，”塔普索巴说，在诊所外面把她5个月大的儿子抱在怀里。"人们将不得不在医院等候，他们可能会没有得到它就离开。"
为了维护发展中国家的冷链，国际组织监督安装了数万台太阳能疫苗冰箱。从疫苗制造到给病人使用，保持疫苗在稳定的温度下也需要移动制冷、可靠的电力、良好的道路，最重要的是，需要提前计划。
对于像布基纳法索这样的贫穷国家来说，接受冠状病毒疫苗的最佳机会是通过世界卫生组织和Gavi疫苗联盟领导的Covax倡议。Covax的目标是订购多种有希望的候选疫苗，并公平分配成功的疫苗。
几个月前，联合国儿童基金会在哥本哈根开始为全球分发奠定基础。在世界上最大的人道主义援助仓库，后勤人员正试图通过吸取过去的教训来预见短缺，特别是围绕全球口罩和其他防护设备短缺的春季混乱，这些口罩和其他防护设备被从机场停机坪征用或被盗并在黑市上交易。
根据世卫组织的数据，目前有42种冠状病毒疫苗候选物正在临床试验中，另有151种正在临床前评估中。最有可能出现在Covax混合物中的必须储存在2到8摄氏度(25-46华氏度)的环境中。
辉瑞公司的一名候选人是需要在超低温下储存的高级测试人员之一。该公司为其疫苗设计了一个特殊的手提箱，表示对Covax感兴趣，并与美国、欧洲和日本签署了合同。
即使在美国和欧洲的医院里，零下70摄氏度的医用冰柜也很少。许多专家认为，经历了2014年至2016年埃博拉疫情的西非国家可能是最合适的位置，因为针对这种病毒的疫苗也需要超低温储存。
然而，根据德国物流公司DHL的一项研究，对于世界上三分之二以上的国家来说，先进技术还遥遥无期。研究称，与此同时，数十亿人生活在没有必要基础设施来维持现有疫苗或更传统冠状病毒候选物冷链的国家。
疫苗流失的机会随着疫苗传播的距离越来越远。敦豪估计，需要15，000次货运航班才能为整个地球接种新冠肺炎疫苗，这使得飞机和干冰等潜在物资的全球供应能力捉襟见肘。
DHL首席商务官Katja Busch说:“我们需要为冷链中的每个缺口找到一座桥梁”。“我们在谈论投资...作为一个社会，这是我们必须做的事情。”
免疫联盟和儿童基金会在大流行前努力向非洲和亚洲大部分地区提供疫苗冷藏设备，自2017年以来已安装了40 000套设施。联合国儿童基金会现在向各国政府提供一份清单，列出他们需要什么来维持疫苗供应链，并要求他们制定一个计划。
“政府负责最终需要发生的事情，”本杰明·施赖伯说，他是联合国儿童基金会疫苗项目的负责人之一。
一旦疫苗出厂，全球冷链就会出现裂缝。集装箱船不能冷藏保质期有限的药品。空运疫苗的成本要高得多，航空货运现在才从与大流行相关的边境关闭中恢复过来。
即使航班足够冷和频繁，空运也会带来其他潜在的危险。世卫组织估计，全球多达一半的疫苗因浪费而丢失，有时是由于运输途中受热或小瓶破裂。冠状病毒疫苗将是世界上最受欢迎的产品之一，盗窃也是一种危险。
国际航空运输协会全球货运负责人格林·休斯(Glyn Hughes)表示:“它们不能被留在停机坪上争夺，因为它们实际上会被宠坏，没有价值——或者更糟糕的是，人们仍在试图分发它们。”
龙亭·戴，约翰·霍普金斯大学的研究员健康care logistics表示，当冠状病毒疫苗在全球范围内分发时，保持冷链完整需要创造力。免疫联盟和联合国儿童基金会已经尝试用无人机运送疫苗。印度官员提出了在该国庞大的食品储存网络中留出一部分用于冠状病毒疫苗的想法。
“如果人们能想出如何运输冰淇淋，他们就能运输疫苗，”戴说。
当疫苗受热时间过长且不再安全使用时，温度敏感标签会改变颜色，实时交付跟踪以确保疫苗按预期到达目的地，也有助于在交付安全疫苗方面取得进展。
然而，随着疫苗准备离开国家仓库，出现问题的可能性在地面上成倍增加。既然冷链如此脆弱，物流规划至关重要；疫苗运输一到，注射器和处理盒就必须准备好。
联合国儿童基金会(UNICEF)执行主任亨利埃塔·福尔(Henrietta Fore)表示，到今年年底，预计将有5.2亿支注射器预先放置在发展中国家的冠状病毒疫苗上，并绘制出冷藏需求最大的地方，“以确保这些供应在疫苗到达时到达各国”。
印度国家计划采用的最后一种需要冷藏的疫苗是针对轮状病毒的，这是一种典型的影响婴儿和幼儿的胃病。领导该疫苗研究的Gagandeep Kang博士估计，印度的储存能力比冠状病毒疫苗所需的储存能力低30%左右。
在印度和布基纳法索等国家，缺乏公共交通是在疫苗变坏之前让公民接种疫苗的另一个障碍。
在印度最贫穷和最不发达的地区之一经营着两家诊所的Aquinas Edassery博士说，病人必须步行几个小时才能获得医疗保健。埃德塞里说，在一条蜿蜒86公里(53英里)的道路上行驶，越过陡峭的山丘，一次冲刷数月，对Rayagada东区的许多居民来说，这将是一个不可逾越的障碍。
与大多数物流一样，最后一公里(英里)是向需要的人提供冠状病毒疫苗的最困难的部分。在拉丁美洲，也许没有任何地方比委内瑞拉更能让我们看到疫苗冷链是如何急剧偏离轨道的。
当去年的一次停电使全国大部分地区处于一周的黑暗中时，委内瑞拉几个地区的医生报告说疫苗库存减少了。委内瑞拉儿童和儿科协会负责人胡尼阿德斯·乌尔维纳博士说，该国最大的儿童医院不得不丢弃数千剂白喉等疾病的疫苗。
“我们无法阻止冠状病毒或麻疹，”乌尔维纳说。
自那以后，保护冷链变得越来越困难。天然气短缺限制了将疫苗从委内瑞拉的一个地区快速转移到另一个地区的能力。运输过程中保持疫苗冷却的干冰很难找到。在经历了多年的经济衰退后，接受培训以保持供应链完整的医生和其他专业人士也越来越少。
委内瑞拉病理学家阿尔韦托·帕尼兹-蒙多尔菲博士说:“我对疫苗在内陆各州的分发方式并不乐观，因为没有任何基础设施来保证运送——或者说，如果运送了，保证在寒冷的条件下得到充分的保存。”
委内瑞拉是一个极端的例子，但冠状病毒疫苗也可能测试拉丁美洲拥有更强大医疗保健系统的部分地区。在秘鲁，通常运输鱼和牛肉的私营企业提供了他们的卡车，尽管尚不清楚卫生部是否会接受。
护士Zoungrana说，在布基纳法索，当冰箱坏掉时，接种疫苗的日子成了Gampela诊所的一场磨难。从事医院快递业务的工作人员必须购买他们通常负担不起的燃料，并第二次往返首都，以返还任何未使用的剂量。
“我们很痛苦，”几周前骑着摩托车离开公路的宗格拉纳说。
美联社记者本月访问诊所几天后，期待已久的太阳能冰箱就到了。由于技术人员短缺，诊所在储存疫苗之前，一直在等待确保设备能够正常工作。
国家疫苗接种主任伊萨·韦德拉奥果说，在全国范围内，布基纳法索大约缺少1000台临床冰箱，进行疫苗接种的卫生设施中只有不到40%有可靠的冰箱。
多剂量小瓶——相当于疫苗的散装储存——可以大幅降低全球运输成本。但是一旦瓶子被打开，它的保存期会更快地倒计时；如果很少人及时出现进行注射，那么大瓶子里剩下的东西必须被丢弃。
“浪费如此之多，实在令人沮丧。这会导致生命的丧失，痛苦和折磨。这是对资源的浪费，”麻省大学阿姆赫斯特分校研究供应链物流的安娜·纳格内教授说。
据联合国机构冷链专家米歇尔·塞德尔(Michelle Siedel)说，目前，联合国儿童基金会(UNICEF)正押注于20剂量瓶的冠状病毒疫苗，并希望封闭瓶的浪费量将保持在3%以下，而未用完的开放多剂量瓶的浪费量将保持在15%以下。
联合国儿童基金会非洲国家健康和营养负责人让·克劳德·穆巴拉马说，如果今天给布基纳法索注射100万剂冠状病毒疫苗，该国将无法应对。
“如果我们现在必须接种冠状病毒疫苗，此时此刻，这是不可能的，”他说。
——
这个故事纠正了Nagurney教授姓氏的拼写。
——
欣南特从巴黎报道。德里的阿尼鲁德达·戈沙尔、哥伦比亚波哥大的克里斯蒂娜·阿玛里奥和宾夕法尼亚州费尔斯希尔斯的琳达·约翰逊也做出了贡献。
——
Vaccine storage issues could leave 3B people without access
GAMPELA, Burkina Faso -- The chain breaks here, in a tiny medical clinic in Burkina Faso that went nearly a year without a working refrigerator.
The result: Poor people around the world who were among the hardest hit by the virus pandemic are also likely to be the last to recover from it.
The vaccine cold chain hurdle is just the latest disparity of the pandemic weighted against the poor, who more often live and work in crowded conditions that allow the virus to spread, have little access to medical oxygen that is vital to COVID-19 treatment, and whose health systems lack labs, supplies or technicians to carry out large-scale testing.
Maintaining the cold chain for coronavirus vaccines won’t be easy even in the richest of countries, especially when it comes to those that require ultracold temperatures of around minus 70 degrees Celsius (minus 94 F). Investment in infrastructure and cooling technology lags behind the high-speed leap that vaccine development has taken this year due to the virus.
With the pandemic now in its eighth month, logistics experts warn that vast parts of the world lack the refrigeration to administer an effective vaccination program. This includes most of Central Asia, much of India and southeast Asia, Latin America except for the largest countries, and all but a tiny corner of Africa.
The medical clinic outside Burkina Faso's capital, a dirt-streaked building that serves a population of 11,000, is a microcosm of the obstacles.
After its refrigerator broke last fall, the clinic could no longer keep vaccinesagainst tetanus, yellow fever, tuberculosis and other common diseases on site, nurse Julienne Zoungrana said. Staff instead used motorbikes to fetch vials in insulated carriers from a hospital in Ouagadougou, making a 40-minute round-trip drive on a narrow road that varies between dirt, gravel and pavement.
A mother of two who visits the Gampela clinic says she thinks a coronavirus inoculation program will be challenging in her part of the world. Adama Tapsoba, 24, walks four hours under scorching sun to get her baby his routine immunizations and often waits hours more to see a doctor. A week earlier, her 5-month-old son had missed a scheduled shot because Tapsoba’s daughter was sick and she could only bring one child on foot.
“It will be hard to get a (COIVD-19) vaccine,” Tapsoba said, bouncing her 5-month-old son on her lap outside the clinic. “People will have to wait at the hospital, and they might leave without getting it.”
To uphold the cold chain in developing nations, international organizations have overseen the installation of tens of thousands of solar-powered vaccine refrigerators. Keeping vaccines at stable temperatures from the time they are made until they are given to patients also requires mobile refrigeration, reliable electricity, sound roads and, above all, advance planning.
For poor countries like Burkina Faso, the best chance of receiving a coronavirus vaccine is through the Covax initiative, led by the World Health Organization and the Gavi vaccine alliance. The goal of Covax is to place orders for multiple promising vaccine candidates and to allocate the successful ones equitably.
The United Nations' children's agency, UNICEF, began laying the global distribution groundwork months ago, in Copenhagen. At the world’s largest humanitarian aid warehouse, logistics staff are trying to foresee shortages by learning from the past, especially the spring chaos surrounding global shortages of masks and other protective gear that were commandeered off airport tarmacs or stolen and traded on the black market.
Currently, 42 coronavirus vaccine candidates are in clinical trials and another 151 are in pre-clinical evaluation, according to WHO. The ones most likely to end up in the Covax mix must be stored at 2 to 8 degrees Celsius (25-46 F).
A Pfizer candidate is among the ones in advanced testing requiring storage at ultracold temperatures. The company, which has designed a special carrying case for its vaccine, has expressed interest in Covax and signed contracts with the United States, Europe and Japan.
Medical freezers that go down to minus 70 degrees Celsius are rare even in U.S. and European hospitals. Many experts believe the West African countries that suffered through a 2014-16 Ebola outbreak may be the best positioned, because a vaccine against that virus also requires ultracold storage.
For more than two-thirds of the world, however, the advanced technology is nowhere on the horizon, according to a study by German logistics company DHL. Meanwhile, billions of people are in countries that don't have the necessary infrastructure to maintain the cold chain for either existing vaccines or more conventional coronavirus candidates, the study said.
Opportunities for vaccines to be lost expand the farther a vaccine travels. DHL estimated that 15,000 cargo flights would be required to vaccinate the entire planet against COVID-19, stretching global capacity for aircraft and potentially supplies of materials such as dry ice.
“We need to find a bridge” for every gap in the cold chain, DHL chief commercial officer Katja Busch said. “We’re talking about investments ... as a society, this is something we have to do.”
Gavi and UNICEF worked before the pandemic to supply much of Africa and Asia with refrigeration for vaccines, fitting out 40,000 facilities since 2017. UNICEF is now offering governments a checklist of what they will need to maintain a vaccine supply chain and asking them to develop a plan.
“The governments are in charge of what needs to happen in the end,” said Benjamin Schreiber, who is among the directors of UNICEF’s vaccination program.
Cracks in the global cold chain start once vaccines leave the factory. Container ships are not equipped to refrigerate pharmaceutical products with a limited shelf life. Shipping vaccines by air costs a lot more, and air cargo traffic is only now rebounding from pandemic-related border closures.
Even when flights are cold and frequent enough, air freight carries other potential hazards. WHO estimates that as much as half of vaccines globally are lost to wastage, sometimes due to heat exposure or vials breaking while in transit. With coronavirus vaccines, which will be one of the world’s most sought-after products, theft is also a danger.
“They can’t be left on a tarmac and fought over because they would actually be spoiled and they would have no value — or worse still, people would still be trying to distribute them,” said Glyn Hughes, the global head of cargo for the International Air Transport Association.
Tinglong Dai, a Johns Hopkins University researcher who specializes in health care logistics, said creativity will be needed to keep the cold chain intact while coronavirus vaccines are distributed on a global scale. Gavi and UNICEF have experimented with delivering vaccines by drone. Indian officials have floated the idea of setting aside part of the country’s vast food storage network for the coronavirus vaccines.
“If people can figure out how to transport ice cream, they can transport vaccines,” Dai said.
Temperature-sensitive labels that change color when a vaccine is exposed to heat too long and no longer safe to use, and live delivery tracking to ensure vaccines reach their destinations as intended also have allowed for progress in delivering safe shots.
Yet chances for something to go wrong multiply on the ground as vaccines are prepped to leave national depots. Since the cold chain is so fragile, logistics planning is crucial; syringes and disposal boxes must be available as soon as vaccine shipments arrive.
By the end of the year, UNICEF expects to have 520 million syringes pre-positioned for coronavirus vaccines in the developing world and maps of where the refrigeration needs are greatest "to ensure that these supplies arrive in countries by the time the vaccines do,” Executive Director Henrietta Fore said.
The last vaccine requiring cold storage that India’s national program adopted was for rotavirus, a stomach bug that typically affects babies and young children. Dr. Gagandeep Kang, who led the research for that vaccine, estimated that India has about 30% less storage capacity than it would need for a coronavirus vaccine.
In countries such as India and Burkina Faso, a lack of public transportation presents another obstacle to getting citizens inoculated before vaccines go bad.
Dr. Aquinas Edassery, who runs two clinics in one of India's poorest and least developed regions, said patients must walk for hours to receive health care. The trip on a single road that winds 86 kilometers (53 miles) over steep hills and washes out for months at a time will pose an insurmountable barrier for many residents of the eastern district of Rayagada, Edassery said.
As with most logistics, the last kilometer (mile) is the hardest part of delivering a coronavirus vaccine to the people who need it. In Latin America, perhaps nowhere more than Venezuela provides a glimpse into how the vaccine cold chain could go dramatically off course.
When a blackout last year left much of the nation in the dark for a week, doctors in several parts of Venezuela reported losing stocks of vaccines. The country’s largest children’s hospital had to discard thousands of doses of vaccines for illnesses like diphtheria, according to Dr. Huníades Urbina, head of the Venezuelan Society of Childcare and Pediatrics.
“We won’t be able to halt either the coronavirus or measles,” Urbina said.
Preserving the cold chain has only grown more difficult since then. Gas shortages limit the ability to move vaccines quickly from one part of Venezuela to another. Dry ice to keep vaccines cool during transport is harder to find. And after years of economic decline, there also are fewer doctors and other professionals trained to keep the chain intact.
“I’m not optimistic on how the vaccine would be distributed in the inner states because there is no infrastructure of any kind to guarantee delivery — or if it gets delivered, guarantees the adequate preservation under cold conditions,” Dr. Alberto Paniz-Mondolfi, a Venezuelan pathologist, said.
Venezuela presents an extreme example, but a coronavirus vaccine also is likely to test parts of Latin America with more robust health care systems. In Peru, private businesses that typically transport fish and beef have offered their trucks, though it remains unclear whether the Health Ministry will accept.
Back in Burkina Faso, vaccination days became an ordeal at the Gampela clinic when the refrigerator went out, said Zoungrana, the nurse. Staff members on hospital courier runs must buy fuel they often can’t afford and make a second trip to and from the capital to return any unused doses.
“We’re suffering,” said Zoungrana, who was run off the road on her motorbike just a few weeks ago.
Days after journalists from The Associated Press visited the clinic this month, a long-awaited solar refrigerator arrived. With technicians in short supply, the clinic was waiting to be sure the appliance would function properly before stocking it with vaccines.
Nationwide, Burkina Faso is about 1,000 clinical refrigerators short, and less than 40% of the health facilities that conduct vaccinations have reliable fridges, national vaccination director Issa Ouedraogo said.
Multi-dose vials — the equivalent of bulk storage for vaccines — can drastically reduce global transportation costs. But once a vial is opened, its shelf life counts down even faster; if too few people show up for their jabs in time, whatever remains in the larger vials must be discarded.
“It’s really upsetting to have wastage like that. It’ll result in loss of lives and pain and suffering. It’s a waste of resources, ” said University of Massachusetts at Amherst professor Anna Nagurney, who studies supply chain logistics.
For now, UNICEF is betting on 20-dose vials of coronavirus vaccine and hoping that the amount wasted will stay below 3% for closed vials and 15% for open multi-dose vials that do not get used up, according to Michelle Siedel, one of the U.N. agency’s cold chain experts.
If Burkina Faso were given 1 million doses of a coronavirus vaccine today, the country wouldn’t be able to handle it, Jean-Claude Mubalama, UNICEF’s head of health and nutrition for the African nation.
“If we had to vaccinate against the coronavirus now, at this moment, it would be impossible,” he said.
———
This story corrects the spelling of professor's last name to Nagurney.
———
Hinnant reported from Paris. Aniruddha Ghosal in Delhi, Christine Armario in Bogota, Colombia, and Linda A. Johnson in Fairless Hills, Pennsylvania, also contributed.
———
Follow all of AP’s coronavirus pandemic coverage at http://apnews.com/VirusOutbreak and https://apnews.com/UnderstandingtheOutbreak
