Vibrio gastroenteritis in Louisiana: a prospective study among attendees of a scientific congress in New Orleans.

The incidence of diarrhea associated with infection by Vibrio species was investigated among attendees at the 1986 Interscience Conference on Antimicrobial Agents and Chemotherapy held in New Orleans. Twelve percent of respondents reported diarrhea; the risk of diarrhea was significantly higher in those who ate raw or cooked oysters (relative risk = 1.5, P = .005). At least one Vibrio species was recovered from 51 (11%) of 479 persons submitting stool specimens; however, only 15 (29%) of those with a positive stool culture also reported diarrhea. Of the five Vibrio species identified, V. parahaemolyticus was most common and was most strongly associated with diarrhea. V. cholerae serogroup O1 was not isolated despite the occurrence of a cholera outbreak during the same time period in Louisiana. Cultures of raw and cooked seafood served in local restaurants yielded five different Vibrio species. Although asymptomatic passage of Vibrio organisms was common among persons eating seafood, the risk of Vibrio gastroenteritis was low.

Cholera in Louisiana. Widening spectrum of seafood vehicles.

The largest cholera outbreak in the United States in over a century occurred in Louisiana from August through October 1986. Eighteen persons in 12 family clusters had stool culture or serologic evidence of infection with toxigenic Vibrio cholerae 0-group 1. Thirteen of these persons had severe diarrhea, and 4 required intensive care unit treatment. Although all 18 survived, 1 96-year-old woman with suspected cholera died shortly after hospital admission. A case-control study showed that case-patients were more likely than neighborhood control subjects to have eaten cooked crabs or cooked or raw shrimp during the week before illness. Case-patients who ate crabs were more likely than control subjects who ate crabs to have undercooked and mishandled the crabs after cooking. A third vehicle from the Gulf waters, raw oysters, caused V cholerae 01 infection in two persons residing in Florida and Georgia. All three seafood vehicles came from multiple sources. Stool isolates from the Louisiana case-patients were genetically identical to other North American strains isolated since 1973, but differ from African and Asian isolates. While crabs are the most important vehicle for V cholerae 01 infection in the United States, shrimp and oysters from the Gulf coast can also be vehicles of transmission. A persisting reservoir of V cholerae 01 along the Gulf coast may continue to cause sporadic cases and outbreaks of cholera in Gulf states and in states importing Gulf seafood.

Homicide victims in New Orleans: recent trends.

Data are presented on 694 criminal homicide victims killed in the city of New Orleans during four years; 1979, 1982, 1985, and 1986. The homicide rate for black males was 6.5 times higher than that for white males for the years studied. Over 70% of victims were killed by handguns. When victims were assigned to one of five socioeconomic strata, homicide rates for blacks exceeded those for whites by a factor of at least 2.5 times for each socioeconomic stratum. White victims were more likely than were black victims to be legally intoxicated at the time of death, but black victims were nearly four times more likely to have illicit drugs other than alcohol detected. During the time period investigated, there was a marked decrease in the number of victims with pentazocine and tripelennamine ("Ts and blues") detected and an abrupt increase in the number of victims with detectable phencyclidine and cocaine levels. Further studies are needed to investigate risk factors for homicide victimization so that effective intervention strategies can be employed.