Highly pathogenic avian influenza (HPAI) and virulent Newcastle’s disease (vND) can be transmitted by:

• A. Feces and respiratory secretions
• B. Biological vectors
• C. Contaminated fomites
• D. Both A and C

Answer: (D)

Transmission of HPAI and virulent Newcastle disease primarily occurs through shedding in feces and respiratory secretions and through contact with contaminated inanimate objects. Infected birds release virus in their droppings and in aerosols from coughing or sneezing, which can contaminate water, soil, and surfaces. When healthy birds come into contact with these secretions or with contaminated objects—such as equipment, cages, clothing, footwear, vehicles, or feeding and watering systems—the virus can spread. Biological vectors are not the main route of transmission for these diseases; while mechanical spread by contaminated items can occur, the established and most important pathways are fecal and respiratory shedding and contaminated fomites. Therefore, the best answer is that transmission occurs via both feces/respiratory secretions and contaminated fomites.