由于各州继续向急切等待灾难性疾病缓解的国家推出第一枪的稀缺药品，美国对另一名候选COVID-19疫苗的研究周一开始进行。
公共健康专家说，除了两个选项的疫苗目前正在分配-一个由辉瑞公司和它的德国合作伙伴BioNTech，另由Moderna的制造-是积累足够的出手为全国乃至世界都至关重要。
Novavax Inc.制造的候选人是在美国进行最后阶段测试的第五名候选人。需要大约30,000名志愿者来证明这种注射（与辉瑞和Moderna竞争对手不同）是否真的有效并且安全。
Anthony Fauci博士说：“如果您想拥有足够的疫苗来为美国所有想接种疫苗的人（最多占总人口的85％）进行疫苗接种，那么您将需要两家以上的公司。” ，美国顶级传染病专家周一告诉美联社。
根据COVID追踪项目，冠状病毒在全球造成180万人死亡，其中包括在美国的死亡人数超过33万人。这是美国爆发禽流感最致命的月份，到目前为止，在12月，死亡人数约为65,000。在过去的几周里，该国每天屡屡记录死亡3000多人。
美国可能面临严峻的冬季：尽管在圣诞节期间有警告要留在家里避开其他人的警告，但周日仍有近130万人通过了美国的机场，这是自9月份危机爆发以来，美国单日旅客总数最高的一天。 。
特朗普政府的“经速行动”（Operation Warp Speed）预计到1月初已向各州运送了2000万剂辉瑞和Moderna疫苗，这比最初估计的要使州和卫生官员感到沮丧的估计要少。
没有实时跟踪人们获得两种所需剂量中第一剂的速度。截至周一，疾病控制与预防中心已报告在1,140万剂疫苗中接种了210万种疫苗，但该机构知道这一数字已过时。疫苗供应商的报告可能要花费数天才能散布到网站上。
明尼苏达州卡尔顿县的公共卫生官员詹妮·巴塔说：“仅仅因为疫苗到货并不意味着我们可以建立一个现场诊所。”
但是周二，她的机构旨在在急诊诊所为急诊医务人员接种100人疫苗，巴塔希望这可以成为大规模接种疫苗的典范。护士将把疫苗推到排在县拥有的扫雪机车库里的汽车上。一旦司机开枪，他们将在车位等候，以确保在回家之前不会有过敏反应。
她说：“一次为一个人接种疫苗是我们如何摆脱这种大流行的影响。”
疫苗争夺战还笼罩着另一个忧虑：注射疫苗会阻止在英国出现的冠状病毒的新变种并且可能更容易传播吗？福西（Fauci）说，来自英国的数据表明该疫苗仍将对这种病毒起到保护作用，但是美国国立卫生研究院的研究人员将“非常认真地研究它”。
看看全球疫苗竞赛中的领跑者：
遗传密码疫苗
美国基于对辉瑞-BioNTech疫苗的紧急部署以及由Moderna和NIH生产的类似疫苗的研究表明，它们均具有大约95％的有效性。周末，欧洲开始使用辉瑞疫苗注射疫苗，并将于1月6日决定是否增加Moderna疫苗。
这些照片是采用全新技术制作的，该技术为覆盖冠状病毒的刺突蛋白注入了一段遗传密码。信使RNA或mRNA诱使人体产生一些无害的刺突蛋白，足以使免疫系统在以后遇到真正的病毒时起反应。
两种疫苗都必须保持冷冻状态，辉瑞公司必须在极低的温度下注射疫苗，这会使疫苗难以运送到贫困地区或农村地区。
包括德国的CureVac在内的其他公司也在努力开发自己的mRNA候选药物，该公司已在欧洲进行了大规模研究。
蛋白疫苗
Novavax候选产品的制造方式与众不同，它采用了Fauci所谓的“更加可靠和可靠”的技术，该技术仅需要普通制冷即可。这家位于马里兰州的公司在实验室中生长无害的冠状病毒刺突蛋白副本，并掺入增强免疫力的化学药品中。
Novavax已在英国和南非的4,000名后期研究中招募了15,000人。由美国政府资助的最新，规模最大的研究将在美国和墨西哥的115多个地点招募志愿者，并将高危老年人与受到该病毒打击的黑人和西班牙裔社区的志愿者作为目标人群。
“我们必须保护我们的社区和我们的人民，” 75岁的彼得·约翰逊牧师说，他是达拉斯著名的民权活动家，也是最早的志愿者之一。
三分之二的参与者将接受疫苗注射，其余的将进行虚拟注射，这与早期的疫苗研究有所不同，后者为一半的志愿者提供了安慰剂。Novavax研究负责人格里高里·格伦（Gregory Glenn）博士说，这应该可以帮助研究人员招募那些怀疑是参加研究还是等待轮到已有照片的人。
对于许多人来说，这将是一个漫长的等待：辉瑞和Moderna的拍摄首先针对医疗保健人员和疗养院居民，其次是75岁及以上的基本工人。
美国国立卫生研究院主任弗朗西斯·柯林斯博士说：“如果您想对冲赌注，对于那些不在那些高风险人群中的大多数人来说，获得疫苗的最短途径就是报名参加试验。”
特洛伊马疫苗
下一个重大疫苗新闻可能来自强生公司，该公司的目标是生产一种单剂量的COVID-19疫苗。
它以另一种方式制造，它使用一种无害的病毒-一种叫做腺病毒的冷病毒-将刺突基因携带到体内。在12月中旬，强生完成了约45,000名志愿者在美国和其他六个国家的最后阶段的研究。福西（Fauci）预计下个月某个时候会取得初步结果。
在英国，监管机构也正在考虑清除阿斯利康和牛津大学生产的类似疫苗。
在英国，南非和巴西对这些枪击进行的测试表明，它们是安全的并且具有部分保护作用-大约70％。但是，关于该疫苗在55岁以上人群中的效果如何以及如何解释少数人使用不同剂量的疫苗的结果仍然存在疑问。
美国对阿斯利康枪击事件的研究仍在招募志愿者。福西说，研究人员希望它将提供更明确的答案。
中国和俄罗斯的公司也正在生产基于腺病毒的疫苗，并在最终检测结果出来之前就开始对其进行管理。预计阿根廷将很快使用该俄罗斯疫苗。
“杀手”疫苗
钉刺疫苗不是唯一的选择。通过繁殖引起疾病的病毒然后杀死它来制造疫苗是一种较老的方法，它使机体可以窥视病菌本身，而不仅仅是单刺蛋白。
中国在一些国家的最终测试中已经使用了三种这样的“灭活” COVID-19疫苗，并允许某些人在结果之前紧急使用。一家印度公司正在测试自己的灭活候选人。
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美联社健康与科学部获得了霍华德·休斯医学研究所科学部的支持。AP对所有内容全权负责。
A huge U.S. study of another COVID-19 vaccine candidate got underway Monday as states continue to roll out scarce supplies of the first shots to a nation anxiously awaiting relief from the catastrophic outbreak.
Public health experts say more options in addition to the two vaccines now being dispensed — one made by Pfizer and its German partner BioNTech, the other by Moderna — are critical to amassing enough shots for the country and the world.
The candidate made by Novavax Inc. is the fifth to reach final-stage testing in the United States. Some 30,000 volunteers are needed to prove if the shot — a different kind than its Pfizer and Moderna competitors — really works and is safe.
“If you want to have enough vaccine to vaccinate all the people in the U.S. who you’d like to vaccinate — up to 85% or more of the population — you’re going to need more than two companies,” Dr. Anthony Fauci, the top U.S. infectious disease expert, told The Associated Press on Monday.
The coronavirus is blamed for about 1.8 million deaths worldwide, including more than 330,000 in the U.S. This has been the deadliest month of the outbreak in the U.S. yet, with about 65,000 deaths in December so far, according to the COVID Tracking Project. The nation has repeatedly recorded more than 3,000 dead per day over the past few weeks.
And the U.S. could be facing a terrible winter: Despite warnings to stay home and avoid others over Christmastime, nearly 1.3 million people went through the nation's airports on Sunday, the highest one-day total since the crisis took hold in the U.S. nine months ago.
The Trump administration’s Operation Warp Speed expects to have shipped 20 million doses of the Pfizer and Moderna vaccines to states by the beginning of January, fewer than originally estimated to the frustration of states and health officials trying to schedule the shots.
There is no real-time tracking of how quickly people are getting the first of the two required doses. As of Monday, the Centers for Disease Control and Prevention had reports of more than 2.1 million vaccinations out of 11.4 million doses shipped — but the agency knows that count is outdated. It can take days for reports from vaccine providers to trickle in and get added to the site.
“Just because a vaccine arrives doesn’t mean we can put an on-the-spot clinic up and running,” said Jenny Barta, a public health official in Carlton County, Minnesota.
But Tuesday, her agency aims to vaccinate 100 people in a drive-thru clinic for emergency medical workers that Barta hopes could become a model for larger attempts at mass vaccination. Nurses will wheel vaccine to cars lined up in a county-owned snowplow garage. Once the drivers get their shots, they will wait in parking spaces to be sure they don’t have an allergic reaction before heading home.
“Vaccinating one individual at a time is how we’re going to work our way out of this pandemic,” she said.
Yet another worry hanging over the vaccine scramble: Will shots block a new variant of the coronavirus that emerged in Britain and might spread more easily? Fauci said that data from Britain indicates the vaccines still will protect against the virus but that National Institutes of Health researchers will be “looking at it very intensively” to be sure.
A look at the frontrunners in the global vaccine race:
GENETIC CODE VACCINES
The U.S. based its emergency rollout of the Pfizer-BioNTech vaccine and a similar one made by Moderna and the NIH on studies suggesting they are both roughly 95% effective. Europe over the weekend began its first vaccinations with the Pfizer shot, and on Jan. 6 will decide whether to add Moderna's.
These shots are made with a brand-new technology that injects a piece of genetic code for the spike protein that coats the coronavirus. That messenger RNA, or mRNA, induces the body to produce some harmless spike protein, enough to prime the immune system to react if it later encounters the real virus.
Both vaccines must be kept frozen, the Pfizer shot at ultra-low temperatures that complicate its delivery to poor or rural areas.
Additional companies are working toward their own mRNA candidates, including Germany’s CureVac, which has begun a large study in Europe.
PROTEIN VACCINES
The Novavax candidate is made differently, using what Fauci called a “more tried and true” technology that needs only ordinary refrigeration. The Maryland company grows harmless copies of the coronavirus spike protein in the laboratory and mixes in an immune-boosting chemical.
Novavax already has enrolled 15,000 people in a late-stage study in Britain and 4,000 in South Africa. The newest and largest study, funded by the U.S. government, will recruit volunteers at more than 115 sites in the U.S. and Mexico and target high-risk older adults along with volunteers from Black and Hispanic communities, which have been hit hard by the virus.
“We've got to protect our community and our people,” said the Rev. Peter Johnson, 75, a prominent civil rights activist in Dallas who was among the first volunteers.
Two-thirds of participants will receive vaccine and the rest dummy shots, a twist from earlier vaccine studies that gave half their volunteers a placebo. That should help researchers recruit people who wonder whether it’s better to take part in a study or wait their turn for an existing shot, said Dr. Gregory Glenn, research chief at Novavax.
For many people, that would be a long wait: The Pfizer and Moderna shots are slated first for health care workers and nursing home residents, followed by people 75 and older and essential workers.
“If you wanted to hedge your bets, for most people who aren’t in those very high-risk groups, the shortest route to getting the vaccine would be to sign up for a trial,” said NIH Director Dr. Francis Collins.
TROJAN HORSE VACCINES
The next big vaccine news may come from Johnson & Johnson, which is aiming for a one-dose COVID-19 vaccine.
Made in yet another way, it uses a harmless virus – a cold virus called an adenovirus -- to carry the spike gene into the body. In mid-December, J&J finished enrolling about 45,000 volunteers in a final-stage study in the U.S. and a half-dozen other countries. Fauci expects early results sometime next month.
In Britain, regulators also are considering clearing a similar vaccine made by AstraZeneca and Oxford University.
Tests of the shots in Britain, South Africa and Brazil suggested they are safe and partially protective — about 70%. But questions remain about how well the vaccine works in people over 55 and how to interpret results from a small number of people given a different set of doses.
A U.S. study of the AstraZeneca shots is still recruiting volunteers; Fauci said researchers hope it will provide a more clear answer.
Companies in China and Russia also are producing adenovirus-based vaccines and began administering them before the results of final testing came in. Argentina is expected to soon use the Russian vaccine.
“KILLED” VACCINES
Spike-focused vaccines aren’t the only option. Making vaccines by growing a disease-causing virus and then killing it is a still older approach that gives the body a sneak peek at the germ itself rather than just that single spike protein.
China has three such “inactivated” COVID-19 vaccines in final testing in several countries and has allowed emergency use in some people ahead of results. An Indian company is testing its own inactivated candidate.
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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science. The AP is solely responsible for all content.
