Control and prevention of avia influenza in evolving scenario
Frequent outbreaks of highly pathogenic avian influenza (HPAI) across Africa and Eurasia, caused by a type A influenza virus of the H5N1 subtype appears to be out of control and indicates a serious risk of animal and public health all across the globe.The application and usage of vaccination against avian influenzae viruses of the H5 and H7 subtypes, seems to be beneficial in recent times. Vaccination programmes in avian species in developing countries have been recommended recently, however it will require the joint management of local animal husbandry practices and industry compliance to eradicate the disease instead of occurrence of an endemic situation.
While in the developed countries vaccination programme means for the increasing resistance of susceptible animals to reduce the risk of introduction from the reservoir host or to reduce the chance of secondary spread in densely populated poultry regions.
The recent joint summits of OIE/FAO has recommended the application of vaccination using the differentiating infected from vaccinated animals (DIVA) strategy during risk of major spread and depopulation is not desirable or feasible. Specifically in developing countries, extermination of infected animals does not seem to be an appropriate method for reducing the spread of infection. For the success of vaccination campaign crucial points are the implementation of complex territorial strategy containing upgraded bio-security, observation of vaccine efficacy, recognition of field exposure and the relevant management of infected flocks, regardless of vaccination status.