Trump says some routine immunizations will be split into five separate shots. Vaccine experts say it won’t work

President Donald Trump said Friday that his administration is planning to recommend that certain childhood immunizations be broken up into five separate shots, each with a “small amount of the vaccine.” These “20% doses” would each be given six months apart, he said.

“Instead of a child going in and having a tremendous amount of different vaccines pumped into a big proportion of the body … we’re going to recommend that they do five doses marked one, two, three, four, five and that they be given in six-month intervals, so that a small amount of the vaccine gets pumped into the body,” Trump said.

Such a plan would render vaccines ineffective and wouldn’t make them safer, said Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia.

Trump also said Friday that “certain vaccines were taken out because they’re not needed until the child would be much older,” an apparent reference to the federal childhood vaccine schedule — which the administration attempted to overhaul this year before it was temporarily blocked by a federal judge.

It’s unclear which vaccines Trump was referring to at Friday’s news conference; he specifically mentioned only the polio vaccine, which he said has “been amazing.”

Record share of kindergartners missed required vaccines last year as Trump executive order takes aim at state mandates

Trump suggested that the federal vaccination schedule changes he referenced Friday would lead to a “massive reduction in autism,” even though extensive scientific studies of vaccines have yielded no evidence of a connection to autism.

The US Department of Health and Human Services has not responded to CNN’s request for further details about the plans that Trump outlined Friday.

HHS Secretary Robert F. Kennedy Jr. — who was standing by Trump as he outlined the planned vaccine changes — received a standing ovation Thursday at the conference of the anti-vaccine advocacy group Children’s Health Defense , where he gave the keynote. He praised Trump’s embrace of vaccine skeptics, telling the conference attendees, “you have a strong and steadfast friend at the White House” and saying he would “stay in this fight.”

In August, Trump signed an executive order aimed at reshaping the federal government’s approach toward childhood vaccines , insisting that infants should receive fewer immunizations over a longer period and advising that the measles-mumps-rubella (MMR) vaccine be separated into three individual shots, despite little scientific evidence supporting such sweeping changes.

Trump has previously claimed that “large amounts – like vats of vaccine – are currently pumped into your child’s body” and that this supposedly large volume of fluid – “the size of a bottle of soda” – was dangerous.

The standard dose of MMR vaccine given to children around 12 months of age is 0.5 milliliters, or CCs, about one-tenth of a teaspoon.

Bonnie Cash/UPI/Bloomberg/Getty Images

Trump wants to split the MMR vaccine into separate shots. Experts say it’s a bad idea

Trump’s idea to split up the shots “is buffoonery,” said Offit, a vaccine inventor. He noted that vaccines are studied extensively so their dosing schedule is optimized for efficacy and safety, and he said that reducing the amount administered and giving more shots would make it so the vaccines don’t work while doing nothing to increase safety.

“When you create a vaccine, you do a dose response curve, and you’re trying to give the least amount of vaccine that induces an immune response that’s protective. So you don’t want to give too much, where you know you don’t need all that, and you don’t want to give too little, where it’s you know sub-immunogenic,” meaning it wouldn’t induce an immune response. Put more simply, Offit told CNN, “What he’s suggesting would not work. He’s basically saying he wants to give vaccines in a manner in which they wouldn’t be protective.”

Kennedy tells anti-vaccine group he previously led that he’ll ‘stay in this fight’

Offit also pointed out that vaccines don’t overwhelm babies’ immune systems, as they expose us to much less than we encounter every day naturally. “You make a billion new B and T cells every day to handle the onslaught of viruses and bacteria from your environment,” Offit said. “Vaccines are literally a drop in the ocean of what you encounter and manage every day. “The notion that vaccines in any way are overwhelming your immune system, causing chronic disease, is just fanciful.”

CNN’s Tami Luhby, Brenda Goodman and Jen Christensen contributed to this report.

唐纳德·特朗普总统周五表示，他的政府计划建议将某些儿童疫苗接种分成五剂，每剂只含有“少量疫苗”。他说，这些“20%剂量”的疫苗将每剂间隔六个月接种。

特朗普说：“与其让孩子一次性接受大量不同的疫苗注射到身体的大部分区域……我们建议他们接种五剂疫苗，分别标记为一、二、三、四、五，每六个月接种一次，这样每次只有少量疫苗被注射到体内。”

费城儿童医院疫苗教育中心主任保罗·奥菲特博士表示，这样的计划会使疫苗失效，也不会使疫苗更安全。

特朗普周五还表示，“某些疫苗被撤下是因为在孩子年龄更大之前不需要接种”，这显然是指联邦儿童疫苗接种计划——今年，特朗普政府曾试图对该计划进行改革，但被一名联邦法官暂时阻止。

目前尚不清楚特朗普在周五的新闻发布会上指的是哪些疫苗；他特别提到了脊髓灰质炎疫苗，并称其“效果惊人”。

去年，未接种所需疫苗的幼儿园儿童比例创历史新高，此前特朗普的行政命令旨在削弱各州的强制接种规定。

特朗普暗示，他周五提到的联邦疫苗接种计划变更将导致“自闭症病例大幅减少”，尽管对疫苗的大量科学研究并未发现疫苗与自闭症之间存在任何联系。

美国卫生与公众服务部尚未回应 CNN 关于特朗普周五概述的计划的更多细节请求。

美国卫生与公众服务部部长小罗伯特·F·肯尼迪（Robert F. Kennedy Jr.）——他当时站在特朗普身边，听他概述疫苗计划的变更——周四在反疫苗倡导组织“儿童健康保护”（Children's Health Defense）的会议上发表了主旨演讲，并获得了全场起立鼓掌。他赞扬了特朗普对疫苗怀疑论者的包容，并告诉与会者，“你们在白宫有一位强大而坚定的朋友”，他还表示自己将“继续这场斗争”。

8 月，特朗普签署了一项旨在重塑联邦政府儿童疫苗接种方式的行政命令，坚持认为婴儿应该在更长的时间内接受更少的免疫接种，并建议将麻疹-腮腺炎-风疹 (MMR) 疫苗分成三剂单独注射，尽管几乎没有科学证据支持这种彻底的改变。

特朗普此前声称，“大量的液体——就像一桶桶的疫苗——目前正在被注入你孩子的体内”，并且这种所谓的大量液体——“相当于一瓶汽水的大小”——是危险的。

给 12 个月左右的儿童接种的麻疹、腮腺炎、风疹 (MMR) 疫苗的标准剂量为 0.5 毫升（CC），约合十分之一茶匙。

Bonnie Cash/UPI/Bloomberg/Getty Images

特朗普想把麻疹、腮腺炎、风疹疫苗分成两剂注射。专家说这是个馊主意。

疫苗发明家奥菲特称，特朗普提出的分次接种疫苗的想法“简直是愚蠢至极”。他指出，疫苗都经过广泛的研究，其接种方案已针对有效性和安全性进行了优化。他还表示，减少疫苗剂量并增加接种次数，不仅无法提高安全性，反而会导致疫苗失效。

“研制疫苗时，要绘制剂量反应曲线，目标是找到能诱导产生有效免疫反应的最小剂量。既不能剂量过大（因为你知道根本不需要那么多），也不能剂量过小（因为剂量不足，无法产生亚免疫原性），”也就是说，剂量过小无法诱导免疫反应。奥菲特告诉CNN，更简单地说，“他（指奥菲特）的建议行不通。他实际上是在说，他想用一种无法产生保护作用的方式来接种疫苗。”

肯尼迪告诉他之前领导的反疫苗组织，他将“继续这场斗争”。

奥菲特还指出，疫苗不会使婴儿的免疫系统不堪重负，因为它们让我们接触到的病原体远少于我们每天自然接触到的。“你每天都会产生数十亿个新的B细胞和T细胞来应对环境中病毒和细菌的侵袭，”奥菲特说。“疫苗对你每天接触和应对的病原体来说，简直是沧海一粟。认为疫苗会以任何方式使你的免疫系统不堪重负，导致慢性疾病的说法，纯属无稽之谈。”

CNN的Tami Luhby、Brenda Goodman和Jen Christensen对本报道亦有贡献。