One Shot, Three Wins: A New Chicken Vaccine

Scientists have made a breakthrough that could protect chickens from three deadly diseases with just one shot. The vaccine uses a harmless strain of the Newcastle disease virus (NDV) as a carrier. Instead of the usual genes, they inserted pieces from a dangerous NDV strain that is common today. They also added two extra genes: one from the H9N2 avian influenza virus and another from a very harmful bursal disease virus. The engineered virus is safe for chickens. Tests showed it does not cause illness and grows at the same rate as its parent strain.When chickens received a single dose through eye or nose, their immune systems produced strong antibodies. After three weeks, the vaccinated birds faced real attacks from all three viruses. None of them died or showed sickness signs. They also shed very little virus, meaning they would spread fewer infections in a flock. This single‑dose vaccine could save farmers millions of dollars. It reduces the need for multiple shots, lowers labor costs, and limits disease spread. The approach also helps protect food supplies by keeping poultry healthy.