Submitted to: Avian Diseases
Publication Type: Review Article
Publication Acceptance Date: July 14, 2012
Publication Date: July 14, 2012
Citation: Suarez, D.L. 2012. DIVA vaccination strategies for avian influenza virus. Avian Diseases. AVIAN DISEASES. 56:836–844.
Interpretive Summary: Avian influenza virus can cause a wide range of disease in poultry including respiratory disease, drops in egg production, to severe disease with a high mortality. One method of prevention and control of disease is by vaccination. One problem with vaccination is that it can interfere with our normal tests to detect birds infected with influenza which detects antibody to influenza in the blood of the birds. Vaccinated birds will also develop antibody that can’t easily be distinguished from natural infection, and therefore different tests are needed to routinely look for infection in birds. This is important because without sensitive, fast, and inexpensive tests to show our flocks are free of influenza infection, we can lose our export markets for poultry and poultry products. DIVA (Differentiate infected from vaccinated animals) vaccination is the idea that special tests can be developed that will allow us to differentiate birds that are vaccinated from those that have been infected. This review describes the different methods of DIVA vaccination. Two different approaches work well experimentally, but further work needs to be done in the field to prove that they work under real world conditions.
Vaccination for both low pathogenic and highly pathogenic avian influenza is commonly used for countries that have been endemic for avian influenza influenza virus, but stamping out policies are common for countries that are normally free of the disease. Stamping out policies of euthanizing infected and at risk flocks has been an effective control tool, but it comes at a high social and economic cost. Efforts to identify alternative ways to respond to outbreaks without widespread stamping out has become a goal for organizations like the World Organization for Animal Health. A major issue with vaccination for avian influenza is trade considerations, because countries that vaccinate are often considered to be endemic for the disease and they typically lose their export markets. Primarily as a tool to promote trade, the concept of DIVA (Differentiate infected from vaccinated animals) has been considered for avian influenza, but the goal for trade is to differentiate vaccinated and not infected from vaccinated and infected animals, because trading partners are unwilling to accept infected birds. Several different strategies have been investigated for a DIVA strategy, but each has advantages and disadvantages. A review of current knowledge on the research and implementation of the DIVA strategy will be discussed with possible ways to implement this strategy in the field. The increased desire for a workable DIVA strategy may push one of these ideas from experimental to the practical.