Distemper vaccinations could save giant pandas

Supply problems, drug risks mean some endangered animals will go unprotected

China's giant pandas are susceptible to canine distemper virus, and surveillance and vaccinations are warranted to support conservation efforts, according to a new report.

Published by the journal Nature on Thursday, the report said that due to the limited supply of some vaccines and the potential risks associated with others, most giant pandas in the Shaanxi Rare Wild Animal Rescue and Research Center, as well as those with other organizations involved in giant panda breeding programs, are not routinely vaccinated.

CDV was reported to have caused the deaths of captive giant pandas as early as 1997 when three pandas died at Chongqing Zoo.

The most recent outbreak in Shaanxi province caused the deaths of five pandas from December 2014 to April 2015. The single panda to survive had been vaccinated.

Xia Xianzhu, one of the authors of the report and an academician at the Chinese Academy of Engineering, said the immune responses elicited by vaccination were not sufficient to prevent naturally-acquired CDV infection, but may have lessened the severity.

The giant panda is native to China and is categorized as endangered on the International Union for Conservation of Nature's Red List of Threatened Species.

According to the fourth national panda survey, there are 1,864 wild pandas and 375 in captivity in China at the end of 2013.

Zhang Hemin, chief of the China Conservation and Research Center for the Giant Panda, said every panda in the center is vaccinated.

Zhang's center was established in the Wolong National Natural Reserve in Sichuan province in the wake of an agreement between the World Wide Fund and the Chinese government in 1980. It is home to 210 pandas.

Wang Chengdong, director of the animal hospital at the reserve, said that the vaccine came from a company in the United States.

"From 2013 to 2014, the company cut the production of CDV vaccine due to slim profits and small demand, and we had to stop giving the vaccine to pandas. Though it resumed production, we are not sure whether it will cut the production line again," Wang said.

"So the China Conservation and Research Center for the Giant Panda is working with the authors of the report to develop a CDV vaccine specifically for China's giant pandas."

Contact the writers at suzhou@chinadaily.com.cn

Viral threat

Canine distemper virus is a single-stranded RNA virus of the Morbillivirus genus and family Paramyxoviridae. Several fatal outbreaks of CDV have been reported in captive wild populations, including lions, tigers and leopards, as well as in free-ranging, wild populations of endangered species such as African wild dogs and wild Amur tigers. CDV transmission to captive animals may occur via direct or indirect contact with infected domestic dogs or wild carnivores. However, the source of the CDV that caused the outbreak among giant pandas remains unclear.