China develops first live vaccine against bird flu By Zhao Huanxin (China Daily) Updated: 2005-12-26 05:27
Chinese scientists have produced the world's first live vaccine against bird flu and Newcastle disease - two killer infections for poultry, the Ministry of Agriculture has announced. The recombinant bivalent vaccine, developed by the Harbin Veterinary Research Institute, will be a great boost to prevention and control of the two epidemics in China as well as in the world, Chief Veterinary Officer Jia Youling told a press conference in Beijing on Saturday. In addition to injection, the vaccine can be administered orally, nasally or by spraying, said Jia, also chief of the ministry's Veterinary Bureau. The mass-application techniques can not only significantly reduce labour costs, but also increase immunity among fowls, Jia said. The shot will also be very inexpensive, as its production cost is only one-fifth of the inactivated vaccines available on the market, he said. While most people are familiar with bird flu, Newcastle infections are endemic to many countries. The latter is also a highly-contagious viral disease affecting both domestic poultry and wild birds, experts said, adding that chickens are the most susceptible. In September, Newcastle outbreaks killed at least 56,700 chicken on the Chinese mainland, according to the latest veterinary bulletin published by the ministry in October. Chinese scientists at the Harbin institute in Northeast China's Heilongjiang Province spent four years to develop the powerful antidote to both Newcastle and bird flu, according to Jia. Employing a technique called reverse genetics, the vaccine uses an attenuated Newcastle vaccine strain LaSota as a vector, according to Bu Zhigao, a chief scientist of the project. Bu said experiments showed the vaccine can also protect mammals, such as mice, from bird flu. Research and production techniques will provide reference for developing new vaccines for human infections of bird flu, Jia said. The ministry expedited the examination and approval process of the new vaccine after the efficacy and security of the vaccine were satisfactorily proved. Mass-production of the new vaccine was approved on December 23, and by the end of this month, 1 billion shots would have been produced, he said. The vaccine will be used from the beginning of next year alongside other vaccines, he said. Intensive vaccination efforts have paid dividends in China's fight against the fatal H5N1 strain of the bird flu virus. By mid-December, 6.85 billion domestic birds had been vaccinated, including more than 5 billion since October, Jia said earlier. As a result, the country has reported only one case of bird flu outbreak this month. China reported six human cases of bird flu this year, involving two fatalities, and 31 outbreaks among poultry. By last Thursday, 30 out of 31 outbreak sites had been lifted out of epidemic isolation, according to ministry sources. Figures on the latest Newcastle disease toll were not immediately available. In a related development, the State Forestry Administration said on Saturday that it would examine the performance of the monitoring stations for wild-animal epidemic diseases across the country. The checks, lasting till February 20, will ensure that the 150 national stations and 402 provincial stations have contingency plans and adequate information reporting mechanism, according to deputy director Zhao Xuemin.
(China Daily 12/26/2005 page1) |
|
|
|
||
|
||