Vaccines are supposed to prevent disease. But for the first time, it is vaccines that are causing diseases in Australian farms. Australian scientists have found that two different vaccines that were used to control an infectious disease in chickens have recombined to create new lethal virus strains that sickens and kills the chickens.
Since 2008, Australian chickens have been suffering from intense outbreaks of a disease called Infectious Laryngotracheitis (ILT). ILT virus is a herpesvirus, one of the group that causes herpes, chickenpox, and glandular fever in humans. For the ILT, the chickens eyes become red and swollen, they cough and gasp for air, and they sometimes bleed from their noses. The survivors produce fewer eggs, leading to severe losses for farmers.
However, the vaccines that were used to control Infectious Laryngotracheitis (ILT) killed up to 18 per cent of infected chickens in New South Wales and Victoria. Sang-Won Lee from the University of Melbourne has found that two vaccines had merged together to create another virus. It’s an irony that the vaccines that were made to protect the lives of chickens became the cause of their death.