The Shanghai government has now admitted that the total number of carcasses found in the Huangpu river has risen to more than 2,800, up from the 1,200 reported earlier. A preliminary investigation showed the dead pigs, which include piglets and mature hogs, had floated down the river from neighboring Zhejiang province, Residents along the river had reported finding dead pigs in the water previously, but local officials took no action.
Shanghai officials are now saying that it has detected traces of a virus that may have killed the pigs. Porcine circovirus, a common disease among hogs that isn’t known (up to now, anyway) to be infectious to humans, was found in a sample taken from the Songjiang section of the Huangpu river. Tests conducted hourly on the river, which provides drinking water for some of the municipality’s 23 million residents, were negative for other diseases including foot-and-mouth, swine fever, hog cholera and blue-ear, it said.
Discovery of the dead pigs is the latest scare in China, where the government has long been criticized for prioritizing health and environmental issues above business and political interests. In January 2012, a cadmium spill in a tributary of the Pearl River triggered panic buying of bottled water, while a 2010 waste leak into a river in southern Fujian province killed almost 2,000 tons of fish.