Leptospirosis

Synonyms: infectious jaundice, meadow fever, canine fever, Stuttgart disease, Vasiliev-Weil disease
Leptospirosis is an infectious disease of farm animals, carnivores, rodents, and humans caused by the Gram-negative bacterium Leptospira. More than 200 serovars are distinguished, which are grouped into 25(23) serogroups. In Russia, 6 serogroups cause the disease.

Biology of leptospirosis development

The typical way of infection with leptospirosis is contact, water, feed. Transmissible route of infection (through tick and insect bites) is also possible. Leptospires penetrate into the organism through mucous membranes of digestive, respiratory, genitourinary systems or damaged skin, and with the blood stream spread to the internal organs (kidneys, liver, lungs), where they begin to multiply intensively from 2-12 days (incubation period). Then the pathogen enters the blood again, releasing a large number of toxins. These toxins often destroy the endothelium of capillaries. The excretion of leptospires from the body occurs 5-7 days after infection and lasts from several weeks to several years, depending on the form of the disease.

Symptoms of leptospirosis

By the nature of the course distinguish acute, subacute and chronic forms of leptospirosis. In acute leptospirosis observed fever, temperature is elevated 40.5-41 C, oppressed state, jaundice of mucous membranes and skin, darkening of urine to brown. Lethality reaches more than 60%. In subacute course the same symptoms are observed as in acute course of the disease, only they are more blurred / erased. Lethality in the subacute form is 30-50%. Often the subacute form turns into a chronic form. In this course of the disease, clinical symptoms are weakly expressed, little noticeable. Body temperature remains normal, sometimes subfebrile (increase of 1-2 C). There are observed disorders of the gastrointestinal tract, liver, kidneys.

Diagnosis is made on the basis of epizootological data, blood tests (antibodies), urinalysis.

Leptospirosis should be distinguished from piroplasmosis, brucellosis, campylobacteriosis, listeriosis, salmonellosis.

Treatment and prevention of leptospirosis

Treatment of leptospirosis consists in injection of antileptospirosis serum (hyperimmune serum against leptospirosis), penicillin antibiotics, and symptomatic therapy (drips, antispasmodics, hepatoprotectors, means to relieve intoxication, etc.).

Preventive measures include annual vaccination of animals with complex or monovaccines of different strains against leptospirosis.