SS4.13 Water Quality of Lakes, Rivers and Coastal Zones
Date: Thursday, June 13, 2002
Location: Poster Session - VCC
ArdiVC, UC,Irvine-UC Coastal Environmental Quality Initiative, Irvine, USA,
Olson, B, H, Univ. of CA, Irvine, Irvine, USA,
Prevalence of Virulence Factors in Aeromonas hydrophila and spp. in Southern California's Coastal Waters
Aeromonas hydrophila and spp. are commonly isolated from wound infections and gastroenteritis cases in the US. The pathogenicity depends on the dose ingested, and aeromonads' ability to produce adherence factors, enterotoxins, and toxin activators. In several marine studies, aeromonad counts exceed fecal coliform concentration. Traditional indicator bacteria fail to predict its occurrence, because it grows in water and are frequently isolated from coastal waters. We examined Aeromonas and its associated toxins in coastal waters of Southern California using culture and MPN coupled with PCR to better understand the potential health risk to bathers. Enterotoxin genes were detected using consensus sequence primers. All samples contained Aeromonas spp. and high densities (>10^5 to < 10^9 cfu/ml) appear associated with storm runoff events. From the Los Angeles, Santa Ana, and San Gabriel Rivers and associated beaches 7/7, 13/16, and 13/14 samples were positive for enterotoxin(s), respectively. Toxin activator sequences are being screened. Data show an infective dose can be ingested or come in contact with a wound during swimming, but expression of these genes, which will be examined, is also required for pathogencity.