Impacts of epizootic ulcerative syndrome on subsistence fisheries and wildlife

Abstract

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. This paper examines what little has been reported on the impacts of EUS on subsistence fisheries and wildlife, or what can be deduced about those impacts, and concludes that there is a need for systematic data collection on the size and socio-economic importance of subsistence fisheries. Such fisheries are often relied upon by the poorest communities, thus food and nutrition security impacts can be significant. Similarly, impacts on wildlife are poorly documented, emphasising the lack of, and the need for, research on and modelling of the ecosystem-level impacts of EUS and other aquatic animal diseases. The history of EUS and several other aquatic animal diseases also brings into question the effectiveness of current measures for controlling the international spread of aquatic animal diseases and calls for a re-think on how best to meet this ongoing challenge.

Aphanomyces invadans: The Causative Agent of the Epizootic Ulcerative Syndrome in Albino Northern Snakeheads

“…In the present study, we confirmed that A. invadans was a causative agent of epizootic ulcerative syndrome (EUS) in AT Northern Snakeheads. Aphanomyces invadans is the primary causative agent of EUS in nearly 170 species, including wild and farmed freshwater and estuarine fish (Herbert et al 2019; Sumithra et al 2020). This pathogen has been documented in many snakehead species, including the Striped Snakehead Channa striata , Bullseye Snakehead C. marulius (Saylor et al 2010), Spotted Snakehead C. punctata (Hande 2014), and BT Northern Snakehead.…”

Biosecurity and the ornamental fish trade: A stakeholder perspective in England

“…There was a solitary SVC case in a fishery in 2017 (FHI, 2017). EUS is considered a primarily tropical and subtropical disease (generally requiring temperatures of >20°C for clinical expression) which has caused widespread economic and environmental losses in fresh and brackish water throughout Asia, Africa and North America (Herbert et al ., 2019). It has a prolific host range; officially 94 species can be naturally infected (OIE, 2019), but further evidence suggests that c .…”

Molecular insights into the mechanisms of susceptibility of Labeo rohita against oomycete Aphanomyces invadans

“…Infection with Aphanomyces invadans is a serious disease of freshwater fishes that is characterized by the presence of oomycete hyphae and necrotizing ulcerative lesions, leading to pathognomonic granulomatous response 1 , 2 . The disease, commonly known as epizootic ulcerative syndrome (EUS), was first reported from ayu in Japan 3 and has subsequently been reported from 20 countries across 4 continents 1 and the disease is spreading to newer areas 4 – 6 .…”

“…The disease, commonly known as epizootic ulcerative syndrome (EUS), was first reported from ayu in Japan 3 and has subsequently been reported from 20 countries across 4 continents 1 and the disease is spreading to newer areas 4 – 6 . To date, more than 160 species of fish have been reported to be susceptible to A. invadans 2 and the host range is expanding 7 – 10 . Furthermore, it is believed that many more species are likely to be susceptible to A. invadans infection 2 .…”

“…To date, more than 160 species of fish have been reported to be susceptible to A. invadans 2 and the host range is expanding 7 – 10 . Furthermore, it is believed that many more species are likely to be susceptible to A. invadans infection 2 . Importantly, due to its broad host range, ability to cause epizootics and potential socio-economic impacts, infection with A. invadans has been included in finfish diseases reportable to World Organization for Animal Health (OIE) 11 , 12 .…”