Vaccines are a critical strategy in disease control and eradication in the food-producing animal health market. However, as most vaccines are essentially weakened versions of the normal virus, one of their limitations is that there can be no way to differentiate vaccinated animals from those that have active disease. One solution to this is the implementation of a DIVA vaccine strategy.
DIVA stands for Differentiating Infected from Vaccinated Animals and may utilise a vaccine (sometimes referred to as a marker vaccine) which is based on a different strain than the infective strain, enabling a diagnostic test to differentiate between vaccine-induced antibodies and antibodies against the infective strain.
Marker vaccines can be based on deletion mutants of wild-type pathogens, subunit vaccines or inactivated whole virus vaccines. The DIVA immune response can be detected by companion diagnostic tests such as enzyme linked immunosorbent assays (ELISA), or lateral flow immunoassays (LFIA).
Lateral flow technology is an ideal platform for a DIVA diagnostic solution as it provides a low cost, rapid result, at the point of use, providing optimal efficiency and improving the control of disease. Special restrictions, which are necessary for infected animals, can be loosened for animals identified as being vaccinated through the use of a diagnostic test.
Animals have to be certified as disease-free before they can be sold internationally, for example, the EU has a ban on trading cattle which are not officially Tuberculosis (TB) free (Directive 64/432/EEC). Interference of the BCG vaccine with bovine TB (bTB) diagnostic tests led to the ban on bTB vaccination of cattle. An effective DIVA test for bTB would allow trade in cattle vaccinated against bTB under the proposed European Animal Health Law. In this scenario, the development of a cost-effective rapid lateral flow solution could be beneficial.
DIVA vaccines were first used for the eradication of Aujeszky disease in pigs, since then they have advanced to cover infectious bovine rhinotracheitis (IBR) of cattle, foot-and-mouth disease (FMD), classical swine fever (CSF), avian influenza infection (H7N1), and more recently Peste des petits ruminants (PPR).
Marker vaccines along with companion diagnostic test kits hold tremendous potential for developing improved tools for eradication and control programs, allowing vaccination while still retaining the possibility of serological surveillance for the presence of infection.
While DIVA tests add to the overall cost of a vaccination strategy, the use of reliable low-cost technology such as lateral flow immunoassays can offer a cost-effective solution.
Abingdon Health develops and manufactures lateral flow immunoassays for multiple industry sectors including the animal health market, under ISO 9001:2015 and ISO 13485:2016 certification and GMP compliance.
We have built an experienced and expert team who have developed tried and trusted methodologies to produce assays for multiple markers in a variety of matrices. Contact us on +44(0) 1904 406082 or [email protected] if you have a requirement for DIVA diagnostic development or the development of a lateral flow assay for any other marker.