Never say never, especially when it's about gammel Moder Jord.
Little is known about the likely more abundant than in mammals families of viruses in fish:
"Within vertebrates, there has been a marked sampling bias towards mammals and birds, even though they represent only a small proportion of total vertebrate diversity. Far less is known about those viruses infecting fish, amphibians and reptiles, despite their abundance, phenotypic diversity and central role in vertebrate evolution."
According to the current scientific knowledge:
"there is no evidence of fish viruses causing human disease or establishing a productive infection, which largely reflects the phylogenetic distance between fish and humans, along with major differences in cell types and cell receptors. However, the frequency with which plant viruses are found in human faecal samples provides compelling evidence for the passive transmission of viruses through food (Chau et al. 2017
) and the consumption of raw fish has been associated with bacterial (group B Streptococcus
) disease in humans (Zhang et al. 2006
; Tan et al. 2016
(So, even if you can't get coronavirus from fish (yet?), sushi can increase the risk of pneumonia, which will finish you off.)
What's been found so far sounds like "why not" (the first linked article):
"In total, we identified 214 distinctive and previously undescribed putative viral species of vertebrates, of which 196 can be considered vertebrate-specific (Fig. 1b, Supplementary Table 2). Hence, these data reveal that RNA viruses are present in greater numbers and diversity in vertebrates other than birds and mammals than previously realized (Fig. 1c). In particular, it was notable that every vertebrate-specific viral family or genus known to infect mammals and birds is also present in amphibians, reptiles or fish (Fig. 1d). For most of the families or genera, the previously known hosts were either mammals (the Arteriviridae, Filoviridae, Hantaviridae and rubivirus) or mammals, birds and reptiles (Arenaviridae, Astroviridae, Bornaviridae, Coronavirinae, influenza virus and rotavirus). This is the first time, to our knowledge, that these viral groups have been identified in fish and/or amphibians (Fig. 1d). Particularly notable was the presence of divergent members of the Arenaviridae, Filoviridae and Hantaviridae families in ray-finned fish, suggesting that these previously mammal-dominated groups have relatives in aquatic vertebrates (Fig. 2). [...] Of particular note was influenza virus, for which we documented new viruses in jawless fish (hagfish), amphibians (Asiatic toad) and ray-finned fish (spiny eel), with the latter forming a sister-group to human influenza B virus (Fig. 2).