Escherichia coli

Medical Microbiology Disease of the Week 2

Classification

Gastroenteritis/intestinal infection

Causative Organism

Escherichia coli (0157:H7)

Epidemiology

reservoir- animals and their environment

port of entry- digestive tract (oral)

transmission- fecal-oral route

Incubation

1-3 days

Pathogenesis

varies; colonization of intestine by epithelial cells

0157:H7- attaches to colon lining and forms diarrhea-inducing lesions; can secrete Shiga toxins that damage blood vessels resulting in intestinal hemorrhage

Symptoms

diarrhea (often bloody, without pus)

abdominal cramps

fever

nausea

vomiting

3-10 day improvement

Complications

severe dehydration, hemolytic-uremic syndrome (HUS)- 5-10%, could cause kidney failure, low platelets

Prevention

good hygiene, pasteurization, avoid dirty water, thoroughly cooked food, proper refrigeration

Treatment

clear liquids, oral rehydration salts, Pepto-Bismol