Leptospirosis
Disease Name:
Leptospirosis
Species Affected: Bovine, Caprine, Ovine, Equine, Porcine, Canine and Human.
About the Disease:
Leptospirosis is an infectious bacterial disease and also an important zoonotic disease, which is
distributed worldwide. It is spread mainly by the urine of the infected animal. It is transmitted
either by direct contact with infectious animal or by exposure to water or soil contaminated by
the urine of infected animals. Rats, Mice and Moles are important primary host. These rodents
pay an important role in transmitting the disease to animals and men. Leptospirosis is an OIE
Reportable Diseases in Multiple Species Disease Category. Leptospirosis is among the world's
most common diseases transmitted to people from animals. The severe form of this disease is
known as Weil's disease, though it is sometimes named as Weil Syndrome.
Animal Affected:
Cattle, Buffalo, Sheep, Goat, Horse, Pig and Dogs are susceptible.
Cause:
Leptospirosis is caused by infection with pathogenic sprirocheate bacteria called Leptospiria
species. They are, so far more than 23 serogroups/serovars and with numerous serotypes have
been identified. L.interrogans , L.hadzo, L.icterrohaemorrhagica etc. are the most common
pathogenic Leptospires.
Source of infection:
Infected or carrier animal in a herd is the source of infection. Infected animals shed Leptospirers
in urine and other secretions such as semen etc. and other animals get infection through
contaminated feed, water and by sexual routes. The organism usually survives in water and in
moist infected area. Rodents also spread the disease to man and animal by their urine containing
large number of Leptospires through contaminated feed and water.
Symptoms:
The characteristic manifestations of the disease are as follows:
1.
2.
3.
4.
Fever
Anaemia
Vomiting
Dyspnoea
5. Haemoglobinurea
6. Icterus (Jaundice)
7. Abortion
Control and Management:
To prevent this zoonotic disease, the following points should be followed:
1. Control of Rodents, the main carrier of this disease by improvement of sanitation and use
of rodenticides cautiously.
2. Infected animal must be segregated from rest of the herd.
3. Adequate care should be made to prevent contamination of drinking water.
4. The disease in humans often is occupationally or recreationally related, so protective and
preventive measures should be taken.
5. Aborted foetus and foetal membranes must be destroyed/buried/burnt.
6. Serological examination of animals can be taken in endemic areas.
7. Pigs, Sheep and Goats are to be kept separated from Cattle.
Vaccines:
1. A killed vaccine containing L.canicola and L. icterahaemorrhgie is used against Canine
Leptospirosis. Dog vaccines are effective for at least one year.
2. No vaccines for cattle and buffaloes are available in the market.
3. Chick embryo attenuated vaccine has been used. Calves should be vaccinated after the age
of 3 months.
Meteorological Occurrence:
It has a worldwide distribution with a higher incidence in tropical climates and after a heavy
rainfall more occurrence of the disease has been reported. Outside of tropical areas, leptospirosis
cases have a relatively distinct seasonality with high incidence rate in rainy season followed by
spring and autumn.
Prepared by:
Dr. Peter N
JRF, NADRS, Manipur.
Disease Investigatory Laboratory
Directorate of Veterinary, & A.H. Services,
Manipur