LEPTOSPIROSIS. (WEIL'S DISEASE, HEMORRHAGIC JAUNDICE, MUD
FEVER, CANICOLA FEVER, SWINEHARD'S DISEASE)
a. General. Leptospirosis is a bacterial disease of wildlife and domestic
animals, and occurs in man only incidentally after exposure to these species or to an
environment contaminated by them. This disease is an occupational hazard to rice field
workers, farmers, and military troops. It is an acute and often severe infection affecting
the liver or other organs. Symptoms include meningeal irritation and hepatic
disturbance. The most common reservoirs are rats, dogs, and cattle and swine. The
incidence of leptospirosis is higher than usually supposed. The Leptospira
icterohemorrhagiae found rats causes the most severe illness. These organisms can
remain in culture contaminated soil for 43 days, and in urine contaminated soil for 15
b. Modes of Transmission. There have been outbreaks among swimmers who
have been exposed to water contaminated by the urine of domestic or wild animals
such as cattle, dogs, swine, rodents, deer, foxes, reptiles, and amphibia (frogs). The
disease can occur through contact of abraded skin with water, moist soil, or vegetation
contaminated with the urine of infected animals. Leptospirosis is an occupational
hazard for sugar cane field and rice workers, sewer workers, veterinarians, miners,
dairymen, fish workers, farmers, animal husbandmen, abattoir workers, and military
men. It is more apt to occur in those areas of the world where agriculture is less
mechanized than North America, or where more intimate contact with livestock occurs.
It is also a recreational hazard to campers, bathers, and sportsmen in infected areas.
Person-to-person transmission is rare. The organisms may be excreted in the urine up
to 11 months. The most common form of transmission in the US is from animal bites,
close contact with the animal's droplets, transmission by aerosolized urine, infected
carcasses/tissues, and by ixodial ticks. Since pets (dogs) have assumed a greater role
in peoples' lives, the possibility of infection is ever present.
c. Signs and Symptoms. In the first or leptospiremic phase lasting from 4 to 9
days, the victim has chills, usually a frontal headache, severe muscle aches, a high
spiking temperature (102F or more), anorexia, nausea and vomiting, and conjunctival
suffusion. The second or immune phase lasts from 6 to 12 days with meningeal
irritation, hepatic disturbance (jaundice or hepatic enlargement), skin rash
(erythematous lesions), and myocarditis. There may be renal manifestations, such as
proteinuria or hematuria.
d. Treatment. The administration of penicillin G (penicillin) dihydrostreptomycin,
or tetracycline hydrochloride within the first few days seems to decrease severity. The
primary supportive care is to hospitalize the patient, provide bed rest, and give
meticulous fluid and electrolyte therapy.