The first commercially available African Swine Fever (ASF) vaccine in the world is currently being field tested for safety and efficacy in Vietnam. While this is an important milestone in ASF control and prevention, we should be aware that this is a modified live virus (MLV) vaccine and a DIVA (differentiate infected from vaccinated animals) diagnostic assay that can distinguish vaccinated pigs from those infected with wildtype ASF viruses has yet to be developed.
To effectively control and eradicate ASF, researchers should continue to develop subunit (proteins and peptides) and nucleotide (DNA and RNA) vaccines that are inherently safer and DIVA compatible. DIVA assays are extremely useful for the control of a newly emerging infectious disease or a foreign animal disease as they can enable the “vaccinate-to-live” strategy by which vaccinated animals can be raised and processed for food production and consumption and/or sold into international trade.
In addition to making safe and efficacious ASF vaccines affordable and available worldwide, we should also prioritize R&D efforts to increase our understanding of ASFV virus survival in the environment and evaluate low-cost and environmental-friendly virucidal disinfectants under field conditions. It has taken a long time to get this far with an MLV vaccine for ASF and let’s hope DIVA vaccines will be field tested soon.