Semi-quantitative risk assessment of avian influenza and newcastle disease virus in backyard chicken in Perak

A semi-quantitative risk assessment of Newcastle disease (ND) and avian influenza (AI) infections was conducted on humans having direct contact with infected village chickens in Perak using the modified Risk Ranger tool. ND and AI can be transmitted to humans by direct contact with infected poultry. The symptoms of AI in humans have ranged from conjunctivitis to influenza-like symptoms (e.g. fever, cough, sore throat, muscle aches) and some of the AI strains can cause infections leading to mortality of the patients. While infections of ND can cause mild conjunctivitis and influenza-like symptoms, the ND virus poses no hazard to human health. In this study, data collected based on exposure and also on estimation of approximately 10,000 people who have direct contact with the chickens. This group of people includes farmers, neighbours, field workers, veterinarians and laboratory workers who are involved in diagnostics activities of disease screening. It was estimated that there will be 18.3 cases of AI and ND infections per year having direct contact with backyard chickens, respectively. The risk ranking index for AI and ND were 70 and 53 respectively. Albeit risk estimated in this study is medium, the potential of backyard chickens as a vehicle of transmission of AI and ND in Perak cannot be neglecte