F. Christian Baldock's scientific contributions

This paper presents the outcomes of a short expert consultation on epizootic ulcerative syndrome (EUS) held during the Fifth Symposium on Diseases in Asian Aquaculture (DAA V), Gold Coast, Australia in November 2002. The aims of the workshop were to review the body of knowledge on EUS, to provide an opportunity for experts to present mainstream and dissenting views on causal pathways and to re-examine issues relating to case definitions, the syndrome’s name and fungal nomenclature. Workshop participants included five invited experts, two session moderators and DAA V attendees. It is now generally accepted that EUS is the same disease as mycotic granulomatosis (MG), red spot disease (RSD) and ulcerative mycosis (UM). In this paper, jointly developed after the workshop by participating experts and moderators, Japanese work on MG is reviewed and the findings related to work done on EUS in Australia, Southeast Asia, South Asia, the United Kingdom and UM in the United States of America. The majority of participating experts, supported by the weight of published evidence as well as ongoing research findings, held the mainstream view that EUS is essentially an aphanomycosis and that Aphanomyces invadans (= A. piscicida) is the only necessary infectious cause. Their arguments are juxtaposed with those of the minority of participating experts who asserted EUS is a polymicrobial infection, involving outbreak specific viral, fungal and bacterial pathogens. A number of case definitions, appropriate for use in field surveys or for laboratory diagnosis, are proposed. The majority of experts supported a new name for the disease, ‘epizootic granulomatous aphanomycosis’ (EGA). It was further proposed that, in other than taxonomic contexts, the term A. invadans (= A. piscicida) be used in any initial reference to the putative causal fungal pathogen and that the name A. invadans be used thereafter. Key issues with a view to unifying the currently opposing views were identified including recommendation for further research work.