Or whether the patient is partially immune, thanks to past exposures.

由于过去的史，一些人会产出对此的免疫力。

Researchers irradiated mosquitoes extracted the malaria causing parasites and injected them into volunteers, 12 out of the 15 who'd been given the highest dose, then developed immunity.”

研究者对蚊子进行放射处理，然后提取出导致疟疾的寄虫，将之注射到志愿者体内，15名志愿者中有12人被注射最高的剂量，然后就产了免疫力。

Experts say there`s a large population of birds in Massachusetts that have no immunity to the virus so that could be a starting point.

专家说，马萨诸塞州有大量鸟类对这种毒没有免疫力，因此这可能是一个源头。

Health officials say people don't have immunities to it.

卫部官员表示，人类（对该）没有免疫力。

While most experts do believe that we're probably going to have some protection after being infected with the coronavirus, we're still not sure just how long that protection will be or how strong.

很多专家认为感染新冠之后我们应该会有免疫力，但我们尚不确定免疫期有多长，免疫力有多强。

Medical experts have said vaccinations and natural immunity in people who've been exposed to the disease are both playing a part in reducing America's cases.

医专家表示，接种疫苗和接触过这种疾的人的自然免疫力都对减少美国的例起到了作用。

It's when at least 60 percent of a population becomes immune to an infectious disease.

当至少60%的人对传染具有免疫力的时候就达到了“群体免疫”。

That's one of the reasons it makes it hard to develop strong immunity to flu, and to raise strong immunity by using a flu vaccine.

这就是为什么人体很难培养出对流感的强大免疫力，并通过使用流感疫苗来提高免疫力的原因之一。

That depends on both how widely it spreads around the world and the degree to which it erodes immunity – either that built up through infection or vaccination.

这取决于它在世界范围内的传播程度，以及它对通过感染或疫苗建立起来的免疫力的侵蚀程度。

Natural immunity from those who've recovered from the disease could factor in as well.

那些从疾中康复的人的自然免疫力可能对目前情况也会有帮助。

Doctors are concerned that COVID could become like the flu for which there's a new vaccine every year because the flu mutates so quickly and immunity wears off quickly as well.

医们担心，新冠毒可能会像每都有新疫苗的流感毒一样，因为流感毒变异太快导致免疫力也会很快消失。

Researchers believe the reasons may be both objective as in happiness boosting immune function and subjective as in happy people being less troubled by a scratchy throat or runny nose.

研究人员认为，这可以从客观和主观两方面来解释。从客观上说，快乐的情绪可以增强人体的免疫力；从主观上说，快乐的人对于嗓子疼、流鼻涕等感冒症状没那么敏感。

If you've been infected with one of the previous variants, how well does that immunity, that infection acquired immunity, protect you against this.

如果你已经感染了之前的一种变异毒，那么因感染获得的免疫力，是否能有效保护人们免受奥密克戎感染呢？

He had developed immunity to the more dangerous disease.

他已对这种更危险的疾产了免疫力。

Infections and hospitalizations are decreasing, and while it's infected both the unvaccinated and the vaccinated some health experts are hopeful that Omicron might leave people with immunity to COVID in the future.

感染和住院例正在减少，虽然未接种疫苗和接种疫苗的人都被感染了，但一些卫专家希望，奥密克戎可能会在未来让人们对新冠毒产免疫力。

And it is this that seems to explain their immunity.

这正是他们免疫力所在。

So if you're in that middle group, you're not likely to die from it.

所以如果你是免疫力差的人，你也不见得一定会死于流感。

It later became apparent that rabbits were developing a degree of resistance to this disease, so that the rabbit population was unlikely to be completely exterminated.

后来，明显看出，兔子对这种疾已产了一定程度的免疫力，所以兔子不可能被完全消灭。

Smoking can alter the oral microbiota by increasing the acidity of saliva, depleting oxygen, influencing oral baterial adherence to mucosal surfaces, and impairing host immunity.

吸烟能通过增加唾液酸度、消耗氧气含量、影响口腔细菌对黏膜表面的附着、降低宿主免疫力等方式，改变口腔微物群。

It targets older adults, people with weakened immune systems, and pregnant women and their newborns.

它的攻击对象是老人，免疫力低下人群，孕妇以及新婴儿。