disease transmission

The role of aquatic animals in global food and nutrition security is increasingly recognised. The global demand for fish is increasing, leading to a need to significantly increase its supply. Securing future fish supplies through sustainable production is a challenge as major resources such as fresh water and land are becoming limited worldwide. Aquaculture and capture fisheries face various threats from both human-mediated and natural environmental change, including climate change. Aquaculture systems and practices are vulnerable to such changes.

Epizootic ulcerative syndrome (EUS), caused by the water mould (Oomycota) Aphanomyces invadans, has spread throughout the world’s major continents over the last 50 years, with the apparent exception of South and Central America. With over 160 susceptible fish species representing 54 families and 16 orders recorded to date, EUS is of international concern and infection with A. invadans is a World Organisation for Animal Health (OIE) listed disease.

Early developmental stages of tilapia, including fertilized eggs were tested positive for TiLV in a previous study. We, therefore, hypothesized that infected broodstock is able to pass the virus to their reproductive organs and then to the fertilized eggs. In order to prove this hypothesis, Nile tilapia (Oreochromis niloticus) broodstock were experimentally infected with TiLV by intramuscular injection and non-infected broodstock were used as control group.