New vaccine bringing hope to millions of poultry farmers

By Wandera Ojanji

Four years ago, Eunice Mutiso, 45, lost her entire flock of chicken, to Newcastle Disease, a highly contagious viral disease affecting birds and considered as one of the most deadly poultry diseases worldwide.

It was not the first time the small-scale farmer from Kyeni Kyamanzaa in Machakos had lost her entire flock to the disease that has no cure, but it may have been the last time for her and many other indigenous poultry keepers.

Although effective vaccines are available from large pharmaceutical companies, they are rarely used by millions of poultry farmers in rural areas due to various challenges such as lack of electricity, cold storage facilities, poor infrastructure and unfavourable packages for small flocks.

Now, Kenya Agricultural Research Institute (Kari) in collaboration with Kenya Veterinary Vaccine Production Institute (Kevevapi) have adopted an effective vaccine,1-2 ND against the disease.

The I-2 ND virus strain, is an avirulent Australian Newcastle Disease virus isolate from University of Queensland Australia, which is free of commercial ownership and is available to government vaccine production laboratories and other agencies in developing countries.

The vaccine is easy to administer through an eye-drop method using a dropper calibrated to deliver 0.1 ml dose of vaccine. Vaccination should commence 14 days to one month before an anticipated outbreak of Newcastle disease with revaccinations every three months.

62 per cent

According to validation studies conducted in Busia (Western), Mwingi (Eastern), Naivasha (Rift valley), Mwea and Nyandarua (Central), under field conditions in free ranging indigenous chicken the vaccine was found to offer 62 per cent protection against Newcastle Disease.

Dr Ann Wachira Kasal Indigenous Chicken Project Principal Investigator, explains that the five districts were selected based on: indigenous chicken population, disease endemicity, and, lack of vaccination history six months prior to administering the vaccine. Selected sites represented the main agro-ecological zones.

The study revealed that less than five per cent of the indigenous chicken have protective antibodies against the causative virus. "This shows that chicken in the study sites are highly susceptible to the virus," says Dr Wachira. "However, after vaccination with a single dose of I-2 ND vaccine the protection level increased to 62 per cent."