Parasitology of one of the world’s foremost aquaculture fish species lacks a One Health Approach

Abstract

Nile tilapia aquaculture has become an important source of affordable animal protein, but its contribution to food security in the Global South is often underestimated. Semi-intensive and intensive farming systems have led to several problems such as fish disease outbreaks, higher parasite loads, mortality, and environmental degradation. To overcome these problems, it is important to understand the biology and ecology of these parasites and address their pathogenic effects. Currently, ~276 parasite species are known to infect Nile tilapia. However, reports on these parasites are fragmentary, with most studies conducted at local level or focusing on only a few parasite species in experimental settings. Therefore, it is a timely and major challenge to summarise the state of knowledge and adequately present the links between human, animal, and environmental health. A review was carried out to identify protists, metazoans, fungi, bacteria, and viruses with impact on the health and production of Nile tilapia, as well as those with zoonotic risk and potential to serve as environmental indicators. However, of the extensive literature available, only 94 peer-reviewed papers met the inclusion criteria. Furthermore, these studies were conducted in only 24 of more than 140 countries that produce Nile tilapia, suggesting that relatively little research has been conducted on the impacts and environmental correlates of these parasites. When comparing the number of parasite species described with the few studies documenting their impacts, large gaps in knowledge remain. Current information on these parasites is not yet applicable to stakeholders involved in production and management. Therefore, it is imperative that both descriptive and experimental studies be conducted to fill these knowledge gaps. By applying a One Health approach and conducting further research, we can gain valuable and strategic information needed by aquaculture stakeholders. This approach will inform sustainable production of Nile tilapia that considers environmental integrity, fish health and welfare, and consumer health.