[ti:What We Know about the COVID Variant from India] [by:www.51voa.com] [00:00.00]更多听力请访问51VOA.COM [00:00.04]India has recorded the world's sharpest increase [00:04.84]in coronavirus infections in recent weeks. [00:09.36]The crisis has put great pressure on the country's health system, [00:15.40]causing hospitals in major cities to run out of beds, [00:20.56]oxygen and medicines. [00:23.88]Scientists are studying whether a variant of the coronavirus [00:30.36]is to blame for the unexpected rise in Indian cases. [00:37.04]The variant, named B.1.617, [00:41.44]has been reported in at least 17 other nations as well. [00:47.28]Here is what health officials know about this variant so far. [00:54.32]Shahid Jameel is a virologist in India. [00:59.44]He said the variant contains a mutation in the spike protein, [01:05.64]the part of the virus that attaches to human cells. [01:10.48]The spike protein is targeted by existing vaccines. [01:16.40]The mutation may mean that the vaccines [01:20.24]offer less protection against the variant. [01:24.24]The World Health Organization (WHO) said the B.1.617 variant [01:33.04]was first identified in India last December. [01:38.52]An earlier version was seen in October 2020. [01:43.52]The WHO has called the virus version a "variant of interest." [01:50.52]That means it may have mutations [01:53.60]that make the virus easier to spread, [01:56.92]cause more severe disease or escape vaccine immunity. [02:03.64]The WHO has called other versions [02:07.20]found in the United Kingdom (UK), [02:09.44]Brazil and South Africa "variants of concern," [02:14.48]suggesting a higher threat level. [02:17.92]The WHO says more study is urgently needed [02:23.04]to find out whether the variants are driving the increases. [02:29.08]Limited research carried out in laboratories [02:32.84]has suggested the variant could be more transmissible. [02:38.04]However, health officials say another highly transmissible variant [02:44.28]that was first discovered in the UK [02:47.52]is behind an increase in cases in some parts in India. [02:52.96]Sujeet Kumar Singh [02:56.00]is head of India's National Center for Disease Control. [03:01.80]He said that in New Delhi, UK variant cases [03:06.36]almost doubled during the second half of March. [03:11.00]But he said the Indian variant has been widely seen [03:16.00]in Maharashtra, the country's hardest-hit state. [03:21.68]Chris Murray is a disease expert [03:24.52]from the University of Washington in the United States. [03:29.04]He said the large amount of cases [03:32.40]seen in a short period of time in India [03:35.84]means there could be what he called an "escape variant." [03:42.00]Such a variant could be overpowering any past immunity [03:47.08]from natural infections in some populations, Murray said. [03:53.64]"That makes it most likely that it's B.1.617," he added. [04:00.36]But Murray also pointed out that more research is needed, [04:05.76]and that the spread is also being driven [04:09.28]by the UK and South African variants. [04:13.20]Carlo Federico Perno is with Rome's Bambino Gesù Hospital. [04:20.60]He said it is very unlikely that the Indian variant [04:25.04]is the only cause of India's sharp increase in cases. [04:31.16]He pointed to large social gatherings as another possible cause. [04:37.52]Indian Prime Minister Narendra Modi has been criticized [04:42.92]for permitting big political gatherings and religious festivals [04:48.28]that turned out to be super-spreader events. [04:52.24]There are some hopeful signs that vaccines may stop the Indian variant. [04:59.04]White House chief medical adviser Anthony Fauci [05:03.64]said early evidence shows that Covaxin, [05:07.64]a vaccine developed in India, is able to effectively fight it. [05:13.24]In the UK, the government's Public Health England [05:18.12]said it was working with international partners to study the B.1.617 variant. [05:26.72]It said there is currently no evidence that the Indian variant, [05:31.60]nor the British or South African variants, [05:35.20]cause more severe disease or make the vaccines less effective. [05:41.44]I'm Bryan Lynn. 更多听力请访问51VOA.COM