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U.S.
Food & Drug Administration Center for Food Safety & Applied Nutrition Foodborne Pathogenic Microorganisms and Natural Toxins Handbook |
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Vibrio cholerae Serogroup Non-O1
| 1. Name of the Organism:
Vibrio cholerae Serogroup Non-Ol |
This bacterium infects only humans and other primates. It is related to V. cholerae Serogroup O1, the organism that causes Asiatic or epidemic cholera, but causes a disease reported to be less severe than cholera. Both pathogenic and nonpathogenic strains of the organism are normal inhabitants of marine and estuarine environments of the United States. This organism has been referred to as non-cholera vibrio (NCV) and nonagglutinable vibrio (NAG) in the past, although at least 139 "O" serogroups have been identified. (Note: for V. cholerae O139, see Chapter 7). |
| 2. Nature of Acute Disease: | Non-Ol V. cholerae gastroenteritis is the name associated with this illness. Although rare, septicemic infections have been reported and deaths have resulted. Some cases are similar to the primary septicemia caused by V. vulnficus. |
| 3. Nature of Disease: | Diarrhea, abdominal cramps, and fever are the
predominant symptoms associated with this illness, with
vomiting and nausea occurring in approximately 25% of
infected individuals. Approximately 25% of infected
individuals will have blood and mucus in their stools.
Diarrhea may, in some cases, be quite severe, lasting 6-7
days. Diarrhea will usually occur within 48 hours
following ingestion of the organism. It is unknown how
the organism causes the illness, although an enterotoxin
is suspected as well as an invasive mechanism. Disease is
caused when the organism attaches itself to the small
intestine of infected individuals and perhaps
subsequently invades. Disease caused by V. cholerae O139 is indistinguishable from cholera caused by V. cholerae O1. See chapter 7. Infective dose - It is suspected that large numbers (more than one million) of the organism must be ingested to cause illness. |
| 4. Diagnosis of Human Illness: | Diagnosis of a V. cholerae non-Ol infection is made by culturing the organism from an individual's diarrheic stool or from the blood of patients with septicemia. |
| 5. Associated Foods: | Shellfish harvested from U.S. coastal waters frequently contain V. cholerae serogroup non-Ol. Consumption of raw, improperly cooked or cooked, re-contaminated shellfish may lead to infection. |
| 6. Relative Frequency of Disease: | No major outbreaks of diarrhea have been attributed to this organism. Sporadic cases occur frequently mainly along the coasts of the U.S., and are usually associated with the consumption of raw oysters during the warmer months. |
| 7. Course of Disease and Complications: | Diarrhea resulting from ingestion of the organism usually lasts 7 days and is self-limiting. Antibiotics such as tetracycline shorten the severity and duration of the illness. Septicemia (bacteria gaining entry into the blood stream and multiplying therein) can occur. This complication is associated with individuals with cirrhosis of the liver, or who are immunosuppressed, but this is relatively rare. FDA has warned individuals with liver disease to refrain from consuming raw or improperly cooked shellfish. |
| 8. Target Populations: | All individuals who consume raw shellfish are susceptible to diarrhea caused by this organism. Cirrhotic or immunosuppressed individuals may develop severe complications such as septicemia. |
| 9. Food Analysis: | Methods used to isolate this organism from foods are similar to those used with diarrheic stools. Because many food isolates are nonpathogenic, pathogenicity of all food isolates must be demonstrated. All virulence mechanisms of this group have not been elucidated; therefore, pathogenicity testing must be performed in suitable animal models. |
| 10. Selected Outbreaks: | Literature references can be found at the links below. |
| Sporadic cases continue to occur all year, increasing in frequency during the warmer months. | |
| MMWR 44(11):1995 | The cholera epidemic caused by Vibrio cholerae O1 that began in January 1991 has continued to spread in Central and South America. In southern Asia, the epidemic caused by the newly recognized strain V. cholerae O139 that began in late 1992 also has continued to spread. This report updates surveillance findings for both epidemics. |
| MMWR 42(26):1993 | Epidemics of cholera-like illness caused by a previously unrecognized organism occurred recently in southern Asia. This report documents the first case of cholera imported into the United States that was caused by this organism, the newly described toxigenic Vibrio cholerae O139 strain. |
| MMWR 31(39):1982 | In September 1981, an isolated case of non-O1 Vibrio cholerae gastroenteritis occurred in a Laconia, New Hampshire, resident following consumption of raw clams harvested from New England coastal waters. The patient was a previously healthy 40-year-old woman; her recent travel and personal-contact histories were unremarkable. Within 26 hours after eating the clams, she developed acute abdominal cramps, followed by fever and bloody diarrhea. She was treated symptomatically with rest and oral hydration and recovered without sequelae. Her stool culture grew V. cholerae (Smith serotype 361) and no other enteric pathogens. |
| Morbidity and Mortality Weekly Reports | For more information on recent outbreaks see the CDC. |
| 11. Education and Background Resources: | Literature references can be found at the links below. |
| Loci index for genome Vibrio cholerae | Available from the GenBank Taxonomy database, which contains the names of all organisms that are represented in the genetic databases with at least one nucleotide or protein sequence. |
| 12. Molecular Structural Data: | None currently available. |
mow@cfsan.fda.gov
January 1992 with periodic updates
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