200 people attended a party and some of them had diarrhea after 24 hours. They ate oyster, hamburger, ice cream, and potato salad. What's the likely cause? 40 ill from 50 who consumed oyster 50 ill from 135 who consumed hamburger 60 ill from 140 who consumed salad 49 ill from 115 who consumed ice cream

Ans. A. V. parahaemolyticus* parahaemolyticus is capsulated vibrio with peritrichous flagella.* Infections with V. parahaemolyticus can result in two distinct gastrointestinal presentations (including nearly all cases in North America).* The most common presentation is watery diarrhea, usually occurring in conjunction with abdominal cramps, nausea, and vomiting and accompanied in 25% of cases by fever and chills.* Dysentery, the less common presentation, is characterized by severe abdominal cramps, nausea, vomiting, and bloody or mucoid stools.* V. parahaemolyticus contains two type III secretion systems, which directly inject toxic bacterial proteins into host cells.* After an incubation period of 4 hours to 4 days, symptoms develop and persist for a median of 3 days.* V. parahaemolyticus is linked to its ability to cause hemolysis on Wagatsuma agar), i.e., is called Kanagawa phenomenon.* Doxycycline, fluoroquinolones, or macrolides are preferred in this case.Bacterial food poisoningIncubation period, organismSymptomsCommon food sources 1 to 6 Hours Bacillus cereusNausea, vomitingFried riceStaphylococcus aureusNausea, vomiting, diarrheaHam, poultry, potato, egg, salad, mayonnaise, cream pastries 8 to 16 Hours B. cereusAbdominal cramps, vomiting, diarrheaMeats, vegetables, driedbeans, cerealsClostridium perfringensAbdominal cramps, diarrhea (vomiting rare)Beef, poultry, legumes, gravies >16 Hours EnterohemorrhagicE. coliBloody diarrheaGround beef, raw vegetablesEnterotoxigenicE. coliWatery diarrheaSalads, cheese, meatsSalmonella spp.Inflammatory diarrheaBeef, poultry, eggs, dairy productsVibrio choleraeWatery diarrheaShellfishVibrio parahaemolyticusWatery diarrhea (MC)Dysentery (less common)Molluscs, crustaceansShigella spp.DysenteryPotato or egg salad, lettuce, raw vegetablesCampylobacter jejuniInflammatory diarrheaPoultry, raw milk