[ti:Study Suggests Virus Cause of Paralyzing Illness in Children]
[00:00.00]Scientists have found the strongest evidence yet that a virus is to blame
[00:06.48]for a mysterious illness that can quickly paralyze children.
[00:12.62]The very rare condition, called acute flaccid myelitis or AFM, is similar to the polio disease.
[00:25.56]The first reports of the disease came from the American state of California in 2012.
[00:34.44]Since then, the U.S. has experienced an increasingly bigger outbreak
[00:40.79]every other year, from late summer into autumn.
[00:47.32]Doctors have long believed that certain viruses known as enteroviruses caused AFM.
[00:56.48]But they did not have enough evidence to prove it.
[01:02.12]So researchers tried something new.
[01:05.53]They checked patients' spinal fluid for signs the immune system had fought an invading virus.
[01:15.32]Children who got sick had antibodies that target enteroviruses.
[01:22.52]Dr. Michael Wilson is with the University of California, San Francisco.
[01:29.72]He helped lead the research.
[01:32.80]He said the evidence did not prove their idea.
[01:39.00]But it was a powerful sign enteroviruses cause AFM.
[01:46.48]His team reported the findings in the publication Nature Medicine.
[01:53.28]Study co-writer Dr. Riley Bove is with the same university as Wilson.
[02:01.08]Bove's son developed AFM at age four.
[02:07.04]He noted, "If you don't have a cause, you can't have a vaccine."
[02:13.44]Bove added that Wilson developed "a good enough microscope,
[02:18.05]in a sense, to find things they suspected were there."
[02:23.88]About 590 cases of the illness have been confirmed in the U.S. since 2014.
[02:33.36]Cases increased that year, in 2016 and in 2018.
[02:40.88]Only a few were reported in the years in between.
[02:46.68]So far, there have been 22 cases this year.
[02:52.52]Bove's son Luca demonstrates the pattern.
[02:57.52]His whole family caught a cold in the summer of 2014.
[03:03.72]A few days later, Luca woke up with weakness in his neck that traveled down his shoulder.
[03:12.28]Within days, he had body-wide paralysis and trouble breathing.
[03:19.68]He recovered slowly.
[03:22.07]Today, he still has some paralysis in his neck, shoulder and arm.
[03:30.64]Experts believe either a germ or the body's reaction to a germ
[03:35.84]damages nerves in the spinal cords of patients like Luca.
[03:42.08]They are preparing for another possible increase of cases next summer.
[03:49.12]I'm Jonathan Evans. 更多聽力請訪問51VOA.COM