Pathogenesis of Gastroenteritis Caused by Vibrio carchariae in Cultured Marine Fish

Abstract

Serious mortality among the cultured grouper Epinephelus coioides, characterized by a swollen intestine containing yellow fluid (gastroenteritis), occurred in 1993 in Taiwan. A bacterium isolated from the intestinal fluid and head kidney of moribund groupers was identified as Vibrio carchariae. Since then, the same Vibrio species has also been isolated from moribund black sea bream Acanthopagrus schlegeli, yellowfin sea bream A. latus, Japanese sea bass Lateolabrax japonicus, and red drum Sciaenops ocellatus suffering from the same syndrome. Each isolate was virulent to the respective fish. Recently, a similar syndrome, flounder infectious necrotizing enteritis, also caused by V. carchariae in summer flounder Paralichthys dentatus, was reported in Rhode Island. The extracellular products (ECPs) of V. carchariae strains EmI82KL (from grouper), Rd (from red drum), and SfUSA (from summer flounder, U.S.A.) were virulent to the grouper or red drum. A 33-kDa serine protease partially purified from the ECP of strain EmI82KL was lethal to the fish. All the moribund or killed fish exhibited gastroenteritis except those killed within 12 hours. This report is the first to show that intraperitoneal injection of the ECP or protease in the fish is virulent and can reproduce gastroenteritis. The serine protease was suggested as a major toxin in the grouper or red drum secreted by V. carchariae.

Mass Mortality of Japanese Abalone Haliotis discus hannai Caused by Vibrio harveyi Infection

“…The LD50 value estimated in the injection trial was 6.4×10 5 CFU g −1 per body. Numerous V. harveyi strains have been reported to exhibit pathogenicity toward a wide range of marine vertebrates and invertebrates such as sharks 3,9,10) , groupers 16,38) , flounder 31) , salmon 39) , sea bass 24) , rock robster 6) , penaeid shrimps 2,25) , and abalone 18,20) . In most cases, the vibrio pathogens were reported to be V. carchariae.…”

“…Then, the bacterium might increase its mass on the surface for up to 5 days since the bacterial mass has been beyond the lethal dose against the host animal. However, diseases caused by V. harveyi infections were gastroentelitis, vasculitis, and eye disease 3,16,31,38) . Invasion from the foot muscle of a cultured abalone, H. diversicolor, was also reported 20) .…”

“…V. harveyi has been reported to be a luminescent marine bacterium 13) . Numerous V. harveyi strains, however, were recently reported to exhibit pathogenicity toward sharks 3,9,10) , groupers 16,38) , summer flounder 31) , salmonid fish 39) , dentex, gilthead sea bream, European sea bass 24) , rock lobster 6) , penaeid shrimps 2,25) , and abalone 18,20) . V. harveyi is presently recognized as a fish and shellfish pathogen 4) .…”

Raw oysters can be a risk for infections

“…Vibrio carchariae has been described as an etiologic agent for some fish in cultivations. 27 Pereira et al 28 reported that forty samples of mangrove oysters (Crassostrea rhizophorae) served raw in 15 restaurants in Rio de Janeiro were evaluated in order to investigate the presence of Vibrio spp. They found that Vibrio parahaemolyticus, Vibrio carchariae, Vibrio alginolyticus and Vibrio vulnificus were the main species (> 60 %) isolated from raw oysters.…”

Bacteriophage remediation of bacterial pathogens in aquaculture: a review of the technology

“…It is probably best known as the epidemiological agent responsible for luminosis vibriosis in shrimp, a disease characterized by slow growth, loss of appetite, and high shrimp mortality. It has also been associated with diseases in abalone (Haliotis tuberculata), 61 cobia (Rachycentron canadum), 62 rock lobster (Jasus verreauxi), 63 grouper (Epinephelus coioides), 64 red drum (Scaienops ocellatus), 65 salmonids, 66 summer flounder (Paralichthys dentatus), 67 pearl oysters (Pinctada maxima), 68 and other species of fish and shellfish. Depending on the fish and shellfish species, V. harveyi can also cause a host of other symptoms ranging from hemorrhaging, necrotizing enteritis, and gastroenteritis, to high mortalities without overt symptoms.…”