e. Destroying the Typhoid Bacilli. A search for typhoid bacilli in water
supplies is impractical. Instead, finding another bacterium, Escherichia coli, which is a
normal inhabitant of the human digestive tract, is presumptive evidence of fecal
pollution of water. When E. coli is found in water, the water is considered contaminated
and a possible vehicle for typhoid fever and other diseases for which human excreta is
the source of infection.
f. Treatment. Chloramphenicol is used as specific therapy. The patient should
be isolated in a fly proof room. Immunization is considered less important than
g. Control Measures. In addition to the control measures discussed in section
II, the following should be carried out:
Trace and treat contacts and carriers
Exclude cases, carriers, and familial contacts from food handling until
cultures of feces and urine are negative for typhoid bacilli.
Maintain medical surveillance of patients for at least one month after
onset and then until cultures of feces and urine are negative.
a. Identification. Cholera is an acute bacterial infection of the intestine. It is
presently endemic in Asia, Africa, and the Americas. It may spread along the routes of
trade to any area of the world.
b. Signs/Symptoms. In severe cases, the disease is characterized by sudden
onset of vomiting, profuse watery diarrhea ("rice water stools"), rapid dehydration, and
collapse. The patient may die within a few hours after onset.
c. Epidemics. In epidemics, which tend to occur explosively, the fatality rate
among untreated cases may be as high as 70 percent.
Epidemics, like those of typhoid, usually are precipitated by widespread
consumption of water contaminated with human feces or vomitus containing the
causative bacilli Vibrio cholerae.
Such epidemics are frequently associated with floods and other
d. Transmission/incubation Period. Thereafter, transmission is continued by
contaminated food handlers and flies with carriers being of little importance. The
incubation period is usually less than 3 days but may vary to 7 days. Cases and
convalescents usually remain infectious from 7 to 14 days after onset of symptoms.