Epidemiological Study of Outbreaks and Sporadic Cases Due to Vibrio parahaemolyticus-Serotype O3: K6 in Aichi Prefecture, Japan, during 1988 and 2001

Abstract

Percentage of the outbreaks by O3:K6 Vibrio parahaemolyticus (V. p) in Aichi Prefecture Japan increased from 3% (3/86) for 1988-95 to 75% (33/44) for 1996-2001. The percentage of the sporadic diarrhea cases caused by O3:K6 V. p in a general hospital in Aichi Prefecture also increased from 0% (0/253) to 61% (135/221) during the same periods. Thermostable direct hemolysin (TDH)-positive O3:K6 were isolated from 95% (19/20) of the outbreak incidents and 100% (135/135) of the sporadic cases. Only one TRH (TDH-related hemolysin)-positive O3:K6 was isolated from one outbreak incident. Percentage of the outbreaks by O3:K6 V. p associated with the consumption of boiled shellfishes increased from 5% (6/117) for 1988-95 to 25% (15/59) for 1996-2001, in particular, boiled crabs and squillas associated outbreaks increased from 2% (2/117) to 17% (10/59) and from 2% (2/117) to 10% (6/59), respectively. From 1,548 raw sea foods sampled in the Nagoya Central Wholesale Market in Aichi Prefecture in 1995-99, one TDH-positive O3:K6 was isolated from one live squilla (1/30). Increase in the percentage of outbreaks associated with TDH-positive O3:K6 V. p after 1996 in Aichi Prefecture was revealed to correlate with the increase in the outbreaks associated with consumption of boiled sea foods, especially boiled crabs as well as squillas. Accordingly, it becomes clear that sanitary handling of these boiled foods is important to prevent outbreaks and sporadic cases of diarrhea caused by O3:K6 V. p infection.

Detection ofVibrio parahaemolyticusin Shellfish by Use of Multiplexed Real-Time PCR with TaqMan Fluorescent Probes

“…The previously reported study in which the toxRS/new or toxRS/old primers were used did not distinguish the newly emerged pathogenic V. parahaemolyticus O3:K6 serotype from the pre-1996 nonpathogenic O3:K6 serotype strains (7,41). Although the pandemic strain has not been isolated since the outbreak in the United States (11,12,17), this pathogen remains prevalent in Asian countries (13,35,(39)(40)(41)61). Therefore, for detection of pathogenic pandemic V. parahaemolyticus O3:K6 serotype strains, it seems that ORF8 is the best target.…”

“…This is of particular concern with molluscan shellfish, such as oysters, which, in addition to commonly being consumed raw, are also known to concentrate microorganisms from the environment during the filter-feeding process (45). In recent years, pathogenic strains of V. parahaemolyticus have been associated with gastroenteritis outbreaks around the world at locations that include Spain, Taiwan, Japan, Russia, India, North America, and Southeast Asia (14,17,33,39,49,59,61). In the United States, a 1997 outbreak in the Pacific Northwest resulted in 209 illnesses and one death (11).…”

Risk of Handling as a Route of Exposure to Infectious Waterborne Cryptosporidium parvum Oocysts via Atlantic Blue Crabs ( Callinectes sapidus )

“…It also emphasizes a need for high hygiene standards to be maintained in facilities and restaurants that are cooking live crabs. Minor inattention to hygiene standards in handling edible crabs resulted in V. parahaemolyticus and V. cholerae outbreaks (14,15,17). After the harvest, blue crabs are usually stored alive for several days in a moist and low-temperature environment, which preserves the infectivity of potential Cryptosporidium oocysts.…”

“…Cryptosporidium-contaminated edible crabs may not cause food-borne cryptosporidiosis via consumption, as the oocysts will most likely be inactivated by adequate steaming or cooking processes; however, handling such crabs will expose the persons involved in the handling and may also contaminate the areas where they are stored. Such epidemiological circumstances have been incriminated in Vibrio cholerae and Vibrio parahaemolyticus outbreaks caused by crabs destined for human consumption (14,15,17). Chesapeake Bay blue crabs, a major seafood item harvested from this region, have been shown to contain V. parahaemolyticus (2).…”

A role of some food arthropods as vectors of human enteric infections

“…bacteria outbreaks caused by crabs were first detected almost twenty years ago [21][22][23][24]. However, the fact that certain halophilic Vibrio spp.…”