What it does do is decrease the severity of infection by Plasmodium falciparum malaria.

镰状细胞特征的作用是减轻恶性疟原虫感染的严重性。

The vaccine tries to stop one type of malaria parasite, Plasmodium falciparum, before it has a chance to wreak havoc.

该疫苗能停止疟疾寄生虫恶性疟原虫的活性，使它不能为非作歹。

There has been some reduction in the proportion of people who are likely to be affected with the falciparum parasite.

可能感染上镰状疟原虫的人口比例已经下降。

AND today, falciparum still kills nearly half a million people each year.

时至今日，恶性疟每年仍会夺去近 50 万人的生命。

The World Health Organization says there are five parasite species that cause malaria in humans. Plasmodium Falciparum is the most deadly.

世卫组织称有5种能导致人类疟疾的寄生虫，镰状疟原虫是最致命的。

Knocking out just three of the 5000 genes in the P. falciparum genome can prevent sporozoites from maturing and reproducing, so they can’t infect the bloodstream.

仅敲除恶性疟原虫基因组中 5000 个基因中的三个，就可以阻止子孢子成熟和繁殖，因此它们无法感染血液。

And then of course there's tubercular meningitis which is caused by the Mycobacterium tuberculosis bacteria, and finally parasitic causes of meningitis like P. falciparum which is the main cause of malaria.

然后当然还有结核性脑膜炎，由结核分枝杆菌引起；最后还有脑膜炎的寄生病因，比如像是恶性疟原虫，也是疟疾的主要病因。

Even the best vaccine developed so far, which was engineered with part of a protein produced by the most dangerous parasite, P. falciparum, only works about a third of the time and requires regular booster doses.

即使是迄今为止开发的最好的疫苗，它是用最危险的寄生虫恶性疟原虫产生的部分蛋白质设计的， 也只有大约三分之一的时间有效， 并且需要定期加强剂量。