Viral Pathogens Threatening Cage‐Cultured Nile Tilapia in Lake Victoria: Epidemiology, Emerging Risks and Integrated Health Management Strategies

Abstract

ABSTRACT The rapid expansion of cage culture for Nile tilapia ( Oreochromis niloticus ) in Lake Victoria is central to food security and profitable development in East Africa. Nevertheless, viral conditions affect the sustainability of this sector, with significant imbalances in livelihood, trade and aquaculture adaptability. This review synthesises current knowledge on five crucial contagions applicable to cage‐cultured tilapia in Lake Victoria: tilapia lake virus (TiLV), infectious spleen and kidney necrosis virus (ISKNV), lymphocystis disease virus (LCDV) and two arising pitfalls, tilapia parvovirus (TiPV) and betanodavirus (NNV). We discuss their taxonomy, epidemiology, clinical presentations and possible impacts on aquaculture in the region. The review identifies environmental and functional threat factors, including high stocking density, seed movement, variability in water quality and integration with wild fish. We also speculate issues related to surveillance, molecular characterisation, hatchery biosecurity and vaccine development as critical gaps in aquaculture growth in the region. While none of these contagions are zoonotic, they can dispose of fish to bacterial pathogens with zoonotic potential, emphasising the significance of a One Health approach. Recommendations include region‐wide coordinated surveillance, investment in molecular diagnostics, harmonised aquaculture health programmes and vaccine development. Addressing these issues will ameliorate viral complaints, strengthen aquaculture sustainability and guard the livelihoods of communities dependent on Lake Victoria fisheries.