Combo Vaccines Show Promise against Bird Flu

Newcastle disease virus (NDV) is a bird killer that has been controlled by routine vaccination in the developed world. Molecular biologist Angela Rmer-Oberdrfer of the Friedrich-Loeffler-Institut in Germany and her colleagues inserted a gene controlling expression of a key flu protein into NDV's genome. The resulting vaccine proved nonlethal in chicks and provoked NDV and flu antibodies in 92 percent of inoculated chickens after three weeks. Vaccinated chickens proved immune to infection by NDV and the H5N2 flu strain that provided the original gene. Naive chickens exposed to either disease invariably died.