听力原文： The World Health Organization says India is starting to halt a recent outbreak of Japanese encephalitis that has killed more than 800 people. The disease, which is caused by mosquitoes and is most prevalent during the annual monsoon, may be better contained next year, with officials hoping to launch a new vaccination campaign. Several-thousand cases of Japanese encephalitis have been reported in India since the end of July. almost all of them in the northern province of Uttar Pradesh. More than 800 patients have died, most of them children. But the World Health Organization says it appears that the Indian health authorities now have a handle on the outbreak. Brant Burkholder is an immunization expert in the Southeast Asia regional office of the WHO, whose territory includes India. What caused the disease?