Outbreak ofVibrio parahaemolyticusGastroenteritis Associated with Alaskan Oysters

Abstract

This investigation extends by 1000 km the northernmost documented source of oysters that caused illness due to V. parahaemolyticus. Rising temperatures of ocean water seem to have contributed to one of the largest known outbreaks of V. parahaemolyticus in the United States.

Vibrio parahaemolyticusO3:K6 Epidemic Diarrhea, Chile, 2005

“…parahaemolyticus toward the boreal and austral latitudes, as demonstrated by the course of this epidemic and the recent Alaskan outbreak, might be the result of climatic changes; a warming trend in seawater was noted in both events ( 2 , 7 ). Expansion of the V .…”

“…To the Editor: Outbreaks of diarrhea and gastroenteritis caused by Vibrio parahaemolyticus have been recently reported in many countries and regions where this pathogen was previously unknown ( 1 , 2 ). In mid-January 2005 (Figure), the number of cases of acute diarrhea produced by V .…”

“…Temperature and salinity have been reported as factors that influence concentrations of V . parahaemolyticus in the oceans ( 2 , 5 , 7 , 8 ). During summer 2005, seawater temperatures ≈19°C were recorded in several places along the coast of Region X where shellfish are collected ( 7 ).…”

“…parahaemolyticus in Region X might also have been encouraged by an expansion of finfish and shellfish aquaculture in that area. As in other parts of the world, expansion of these food industries could provide physical and nutritional substrates for vibrios to persist and propagate when growth is triggered by increases in temperature of seawater ( 1 , 2 , 7 ). …”

Climate Change and Human Health 101

“…For example, Vibrio parahaemolyticus, the leading cause of seafood-associated gastroenteritis in the United States, is typically associated with the consumption of raw oysters gathered from warm-water estuaries. In 2004, an outbreak occurred in Alaska where the consumption of raw oysters was the only significant predictor of illness; the attack rate among people who consumed oysters was 29 percent [12]. All oysters associated with the outbreak were harvested when mean daily water temperatures exceeded 15.0 degrees C (the theorized threshold for the risk of V. parahaemolyticus illness from the consumption of raw oysters).…”