a. Reservoirs. The reservoirs of leptospirosis include cattle, dogs, and swine
among domestic animals; and deer, foxes, skunks, raccoons, opossums, reptiles, and
rodents among wild animals.
b. Transmission. Human infections occur through contact with water or soil
contaminated by urine of infected animals, or by direct contact with infected animals.
c. Occupations Exposed. The disease is considered an occupational hazard
to farmers, sewer workers, veterinarians, and military troops, who live or work in rat-
infested areas. Leptospirosis occurs worldwide.
7-13. SIGNS/SYMPTOMS
The incubation period for leptospirosis is from 2 to 20 days. The clinical illness
lasts from 1 to 3 weeks and is characterized by headache, severe muscular aches,
chills, fever, and conjunctivitis. Infrequently, the patient develops jaundice, renal
insufficiency, and hemorrhages in the skin and mucous membranes. Mortality is very
low if jaundice does not develop; in the presence of jaundice, however, fatality may
reach 15 to 40 percent and is higher among patients over 50 years of age.
7-14. PREVENTIVE MEASURES
Preventive measures against infection include the following:
Protecting workers in hazardous occupations with boots and gloves
Educating the public on modes of transmission and on avoiding swimming or
wading in potentially contaminated water
Rodent control in areas of human habitation, especially rural and recreational
area (picnic areas; lakes, swimming pools)
Segregation of domestic animals from living and working areas of man
Section V. IMMUNIZATION
7-15. IMMUNITY AND RESISTANCE
A susceptible or nonimmune has little resistance against a particular disease
organism and, if exposed to it, is liable to contract the disease. By contrast, an immune
has a high degree of resistance to the organism and, when exposed, does not develop
the disease.
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