HANOI, June 14 (Reuters) - Bird flu has spread to several hundred ducks in a third central province and Vietnam's top agriculture official warned of more human infections after four cases reported since May. A total of 350 ducks died on a farm in Ha Tinh province on Monday and tests have confirmed the birds carried the H5N1 avian flu virus, the Animal Health Department said on Thursday. "We have slaughtered all the remaining ducks in the infected area," an animal health official in the province said. The Ha Tinh infection, the third in central Vietnam after Nghe An and Quang Nam provinces, has brought the number of infected areas nationwide to 17. They include 15 provinces and the cities of Haiphong and Can Tho. State media quoted Agriculture Minister Cao Duc Phat as saying more people could be infected over the next week as eating ducks was common during a festival on June 19. The virus living in unvaccinated poultry has added to the infection risk, he said. On Tuesday, officials said two women, aged 28 and 29, had been infected by the H5N1 virus in the northern provinces of Thanh Hoa and Ha Nam. Doctors said the 28-year-old from Ha Nam province was in serious condition and needed a respirator to breathe. Four people have been found to be infected since May, the first human cases of H5N1 in Vietnam in a year and a half. The two women and an infected slaughterhouse worker were being treated in a Hanoi hospital. A 30-year-old man whose infection was reported on May 24 was discharged from the same hospital on June 4. Last week, doctors said he had been cured. Bird flu has killed 42 people out of 97 cases of infection in Vietnam since the disease re-emerged in Asia in late 2003. The World Health Organisation (WHO) has not confirmed the latest four infections. The government has ordered provincial authorities to target all poultry during a second phase of vaccinations now underway in nearly half of 64 cities and provinces. About 140 million poultry were vaccinated in the first phase early this year. Globally, the H5N1 virus has killed 190 people out of 312 known cases, according to the WHO tally. Hundreds of millions of birds have died or been slaughtered, including nearly 120,000 in Vietnam's latest outbreaks since early May.
