662 Modern Food Microbiology
At least five documented gastroenteritis outbreaks of non-01 V. cholerae occurred prior to 1981.
Those in former Czechoslovakia and Australia (1965 and 1973, respectively) were traced to potatoes
and to egg and asparagus salads, and practically all victims experienced diarrhea. The third outbreak
occurred in the Sudan, and well water was the source. Incubation periods from these three outbreaks
ranged from 5 hours to 4 days. The fourth outbreak occurred in Florida in 1979 and involved 11
persons who ate raw oysters. Eight experienced diarrheal illness within 48 hours after eating oysters,
and the other three developed symptoms 12, 15, and 30 hours after eating. The fifth outbreak, which
occurred in 1980 mainly among U.S. soldiers in Venice, Italy, was traced to raw oysters. Of about
50 persons at risk, 24 developed gastroenteritis. The mean incubation period was 21.5 hours, with a
range of 0.5 hours to 5 days; and the symptoms (and percentage complaining) were diarrhea (91.7),
abdominal pain (50), cramps (45.8), nausea (41.7), vomiting (29.2), and dizziness (20.8). All victims
recovered in 1–5 days, and non-01 strains were recovered from the stools of four.
In regard to V. cholerae 01, 6 outbreaks with 916 cases and 12 deaths were recorded by the CDC for
the years 1973 through 1987. Prior to 1973, the last reported isolation of this organism in the United
States was in 1911.
106 Of the six outbreaks, three were traced to shellfish and two to finfish. A single
case of 01 infection occurred in Colorado in August 1988. The victim ate about 12 raw oysters that were
harvested in Louisiana and within 36 hours had sudden onset of symptoms and passed 20 stools.
31 V.
cholerae 01 El Tor serotype Inaba was recovered from stools. Three outbreaks are summarized below.
1. 1994. A woman in California developed cholera after consuming raw seaweed brought from the
Philippines.
134 The causative strain was V. cholerae 01, serotype Ogawa; it was identified from
stools.
2. 1994. Four persons in Indiana came down with cholera after consuming palm fruit brought from
El Salvador 2 days earlier. V. cholerae 01, serotype Ogawa, biotype El Tor was the etiological
agent.
28
3. 1991. Four of six persons developed cholera in Maryland from the consumption of frozen fresh
coconut milk imported from Thailand.
128 The strain responsible was V. cholerae 01, biotype El
Tor.
With regard to distribution, non-01 strains of V. cholerae have been found in Asia and Mexico in
stools of diarrheal patients along with enteropathogenic E. coli. V. cholerae non-01 was isolated from
385 persons with diarrhea in Mexico City in 1966–1967.
13 In July 1991, a serotype Inaba and biotype
El Tor strain was recovered from an oyster-eating fish in Mobile Bay, Alabama.
32 This isolate was
indistinguishable from the Latin American epidemic strain but differed from the endemic strains. Later
in July and again in September, 1991, another isolate was made from an oyster. This strain continued
to be present until August 1992 when oyster beds were opened. How the Latin American cholera
outbreak strain got into this area is a matter of conjecture. In a study of relative retention rates, oysters
accumulated higher concentrations of V. cholerae 01 than E. coli or Salmonella Tallahassee.
From Chesapeake Bay, 65 non-01 strains were isolated in one study.
63 Throughout the year, their
numbers in waters were generally low, from 1 to 10 cells per liter. They were found only in areas where
salinity ranged between 4% and 17%. Their presence was not correlated with fecal E. coli, whereas
the presence of the latter did correlate with Salmonella.
63 Of those examined, 87% produced positive
responses in Y-1 adrenal, rabbit ileal loop, and mouse lethality assays. Investigations conducted on
waters along the Texas, Louisiana, and Florida coasts reveal that both 01 and non-01 V. cholerae are
fairly common. Of 150 water samples collected along a Florida estuary, 57% were positive for V.
cholerae.
38 Of 753 isolates examined, 20 were 01 and 733 were non-01 types. Of the 20 01 strains, 8
were Ogawa and 12 were Inaba serovars, and they were found primarily at a sewage treatment plant. The
At least five documented gastroenteritis outbreaks of non-01 V. cholerae occurred prior to 1981.
Those in former Czechoslovakia and Australia (1965 and 1973, respectively) were traced to potatoes
and to egg and asparagus salads, and practically all victims experienced diarrhea. The third outbreak
occurred in the Sudan, and well water was the source. Incubation periods from these three outbreaks
ranged from 5 hours to 4 days. The fourth outbreak occurred in Florida in 1979 and involved 11
persons who ate raw oysters. Eight experienced diarrheal illness within 48 hours after eating oysters,
and the other three developed symptoms 12, 15, and 30 hours after eating. The fifth outbreak, which
occurred in 1980 mainly among U.S. soldiers in Venice, Italy, was traced to raw oysters. Of about
50 persons at risk, 24 developed gastroenteritis. The mean incubation period was 21.5 hours, with a
range of 0.5 hours to 5 days; and the symptoms (and percentage complaining) were diarrhea (91.7),
abdominal pain (50), cramps (45.8), nausea (41.7), vomiting (29.2), and dizziness (20.8). All victims
recovered in 1–5 days, and non-01 strains were recovered from the stools of four.
In regard to V. cholerae 01, 6 outbreaks with 916 cases and 12 deaths were recorded by the CDC for
the years 1973 through 1987. Prior to 1973, the last reported isolation of this organism in the United
States was in 1911.
106 Of the six outbreaks, three were traced to shellfish and two to finfish. A single
case of 01 infection occurred in Colorado in August 1988. The victim ate about 12 raw oysters that were
harvested in Louisiana and within 36 hours had sudden onset of symptoms and passed 20 stools.
31 V.
cholerae 01 El Tor serotype Inaba was recovered from stools. Three outbreaks are summarized below.
1. 1994. A woman in California developed cholera after consuming raw seaweed brought from the
Philippines.
134 The causative strain was V. cholerae 01, serotype Ogawa; it was identified from
stools.
2. 1994. Four persons in Indiana came down with cholera after consuming palm fruit brought from
El Salvador 2 days earlier. V. cholerae 01, serotype Ogawa, biotype El Tor was the etiological
agent.
28
3. 1991. Four of six persons developed cholera in Maryland from the consumption of frozen fresh
coconut milk imported from Thailand.
128 The strain responsible was V. cholerae 01, biotype El
Tor.
With regard to distribution, non-01 strains of V. cholerae have been found in Asia and Mexico in
stools of diarrheal patients along with enteropathogenic E. coli. V. cholerae non-01 was isolated from
385 persons with diarrhea in Mexico City in 1966–1967.
13 In July 1991, a serotype Inaba and biotype
El Tor strain was recovered from an oyster-eating fish in Mobile Bay, Alabama.
32 This isolate was
indistinguishable from the Latin American epidemic strain but differed from the endemic strains. Later
in July and again in September, 1991, another isolate was made from an oyster. This strain continued
to be present until August 1992 when oyster beds were opened. How the Latin American cholera
outbreak strain got into this area is a matter of conjecture. In a study of relative retention rates, oysters
accumulated higher concentrations of V. cholerae 01 than E. coli or Salmonella Tallahassee.
From Chesapeake Bay, 65 non-01 strains were isolated in one study.
63 Throughout the year, their
numbers in waters were generally low, from 1 to 10 cells per liter. They were found only in areas where
salinity ranged between 4% and 17%. Their presence was not correlated with fecal E. coli, whereas
the presence of the latter did correlate with Salmonella.
63 Of those examined, 87% produced positive
responses in Y-1 adrenal, rabbit ileal loop, and mouse lethality assays. Investigations conducted on
waters along the Texas, Louisiana, and Florida coasts reveal that both 01 and non-01 V. cholerae are
fairly common. Of 150 water samples collected along a Florida estuary, 57% were positive for V.
cholerae.
38 Of 753 isolates examined, 20 were 01 and 733 were non-01 types. Of the 20 01 strains, 8
were Ogawa and 12 were Inaba serovars, and they were found primarily at a sewage treatment plant. The