Chinese scientists announced they had developed a new vaccine for poultry and mammals to prevent the spread of bird flu, state media reported. The new vaccine is reported to protect chickens for at least 10 months, four months longer than existing drugs. The announcement comes amid a new outbreak of the disease, mostly in Vietnam, that has killed at least 45 people to date. The World Health Organization has warned that 100m people could die if the virus mutated into a form that could pass easily between humans. Reporting on the new vaccine, the China Daily said that waterfowl in rivers and lakes would be injected with the new vaccine, but it gave no details how such an ambitious program was to be carried out.