一种有100年历史的结核病疫苗如何帮助对抗新型冠状病毒

一种有100年历史的结核病疫苗如何帮助对抗新型冠状病毒

As researchers scramble to find new drugs and vaccines for Covid-19. a vaccine that is more than a century old has piqued researchers' interests. The Bacillus Calmette-Guerin vaccine -- which was first developed to fight off tuberculosis -- is being studied in clinical trials around the world as a way to fight the novel coronavirus.

在研究人员争相寻找针对Covid-19的新药和疫苗之际，一种已有一个多世纪历史的疫苗引起了研究人员的兴趣。卡介苗最初是为了抗击结核病而研发的，目前正在世界各地进行临床试验，作为对抗新型冠状病毒的一种方式。

Tuberculosis and Covid-19 infection are two very different diseases -- TB is caused by a type of bacteria while Covid-19 is caused by a virus, for starters. But the BCG vaccine might help people build immune responses to things other than TB, causing "off-target effects," according to Dr. Denise Faustman, director of immunobiology at Massachusetts General Hospital and associate professor of medicine at Harvard Medical School.

结核病和Covid-19感染是两种非常不同的疾病，首先，结核病是由一种细菌引起的，而Covid-19是由一种病毒引起的。但是，据马萨诸塞州总医院免疫生物学主任、哈佛医学院副教授丹尼斯·福斯特曼博士说，卡介苗可能有助于人们对结核以外的疾病建立免疫反应，造成“脱靶效应”。

"In other words, in clinical trial format, people started picking up positive benefit from getting the vaccine that had nothing to do with tuberculosis," she said. Faustman has studied how the BCG vaccine affects people with Type 1 diabetes for many years. She is interested in how its off-target effects change the immune system in beneficial ways for people with autoimmune diseases such as Type 1 diabetes.

“换句话说，在临床试验中，人们开始从接种与结核病无关的疫苗中获得积极的益处，”她说。福斯特曼多年来一直在研究卡介苗对1型糖尿病患者的影响。她感兴趣的是它的脱靶效应如何以有益的方式改变免疫系统，以治疗自身免疫性疾病，如1型糖尿病。

Though the exact mechanism for these off-target effects of the BCG vaccine isn't clear, it's believed that the vaccine can cause a nonspecific boost of the immune response.

尽管卡介苗产生这些脱靶效应的确切机制尚不清楚，但人们相信这种疫苗可以引起非特异性的免疫反应。

There is currently no vaccine or treatments approved by the US Food and Drug Administration for the novel coronavirus. While hopeful that the BCG vaccine will prove to be effective against Covid-19 -- as with any of the treatments and vaccines under development -- Dr. William Schaffner, an infectious disease specialist at the Vanderbilt University School of Medicine, admits the concept is a bit unconventional.

目前，美国食品和药物管理局还没有批准针对这种新型冠状病毒的疫苗或治疗方法。尽管卡介苗有望被证明对Covid-19有效，就像任何正在研发的治疗方法和疫苗一样，范德比尔特大学医学院传染病专家威廉·沙夫纳博士承认，这个概念有点不合常规。

"It's such an outside-the-box concept that one would like to be optimistic, but we'll have to wait and see." Schaffner said.

沙夫纳说: “这是一个如此创新的概念，人们会感到乐观，但我们必须拭目以待。” 沙夫纳说。

Several countries around the world are beginning human clinical trials to evaluate the BCG vaccine's efficacy, such as Australia and the Netherlands.

世界上有几个国家正在开展人体临床试验，以评估卡介苗的疗效，如澳大利亚和荷兰。

Faustman and her colleagues are preparing for trials in Boston, which are currently under a multistep review process. Once approved, she and her team members hope to enroll about 4.000 health care workers into the trial.

福斯特曼和她的同事正准备在波士顿进行试验，目前正在进行多步骤审查。一旦获得批准，她和她的团队成员希望能招收大约4000名医护人员参加试验。

The vaccine has been available for more than 100 years and has proved to be relatively safe, Faustman said.

福斯特曼说，这种疫苗已有100多年的历史，并已被证明是相对安全的。

"BCG is heralded by the World Health Organization as the safest vaccine ever developed in the world," she said. "Greater than 3 billion people have gotten it."

她说:“世界卫生组织将卡介苗誉为世界上有史以来最安全的疫苗。”“已经有超过30亿人接种了它。”

Researchers have attempted to look at whether these countries with regular BCG vaccine administration have lower rates of Covid-19-related mortality. One study by researchers in New York found an association between universal BCG vaccination policies in countries and reduced morbidity and mortality for Covid-19. The study has not been peer-reviewed or published in a medical journal.

研究人员试图观察这些定期接种卡介苗的国家是否具有较低的Covid -19相关死亡率。纽约研究人员的一项研究发现，各国普遍接种卡介苗政策与降低Covid-19的发病率和死亡率之间存在关联。这项研究没有经过同行评审，也没有发表在医学杂志上。