Updated 6/9/09
Disease Overview. Leptospirosis is a disease caused by a spiral-shaped
bacteria called Leptospira interrogans. This
bacteria infects humans, dogs, rats, mice,
raccoons, skunks, opossums, cows, pigs, and many other
animals. Transmission
of the bacteria occurs when the urine of an
infected animal contacts the eyes, nose, mouth, or
broken skin of another animal or person.
Exposure to water or mud contaminated with urine may
also be a source of infection. This disease is more common
in humid climates than in arid climates because the
organism survives in a moist environment. There are
several different subtypes of Leptospirosis, and most
cause similar symptoms. Vaccinations for dogs
generally protect against either two or four subtypes of
the bacteria.
Symptoms in dogs may
look like many other diseases, and often include fever,
lethargy, low appetite, vomiting, and
sometimes diarrhea. Yellowed mucus membranes and
increased (or decreased) thirst and urination may be
seen. . General blood tests usually reveal kidney
damage with occasional liver damage as well.
Severe cases, or cases that are treated late, may be
fatal. Special blood and urine tests for Leptospirosis
need to be performed to confirm the infection is
present. In many cases, hospitalization and antibiotics
that kill Leptospira are needed to treat the
illness. The bacteria is excreted in the urine of
the infected animal, and may spread the disease to other
animals or to humans.
Human Health Risk. In the United States, most
human cases of Leptospirosis have occurred after
recreational exposure to contaminated water. Dog
owners who are caring for a dog infected with
Leptospirosis need to we
ar
gloves when caring for the dog, especially after
cleaning up urine.
Local Data in Animals.
Eighteen cases of Leptospirosis cases have been reported
in Los Angeles County dogs between 2002-2008, with seven
deaths. Cases occurred in a wide range of
locations around the county (see map). The
average age of these dogs was 6 years, with a range of 7
months to 12 years. The most common leptospirosis
subtypes seen, as measured by antibody testing, were
autumnalis, bratislava and pomona.
Antibody testing is not completely accurate in
determining the subtype involved.
Leptospirosis vaccination
information was not clear in every case, but in most
cases there was no probable history of vaccination against leptospirosis. In one
fatal case, an older dog apparently became infected
after a raccoon has washed its hands in the the dog's
water bowl before the dog drank the water In another fatal case, a dog became
ill after its home became infested with rats. It
is unknown if the incidence of leptospirosis in local
dogs is truly increasing because local veterinarians
began reporting cases only recently.
Recommendations.
Wildlife Control. Do not attract wildlife that
may carry leptospirosis. Do not eave your pet's
food and water outside at night. Change your pets
food and water every day to prevent them from consuming
anything contaminated by the urine of wild animals.
If you suspect a rat or mouse infestation in your house,
consult an exterminator.
Consider leptospirosis vaccination. It is
unknown if the local risk of leptospirosis infection is
increasing. In many other parts of the United States
leptospirosis infection risk is high. However, it is clear
that leptospirosis infection has occurred locally, even
in dogs that do not leave their own yard.
PRINTABLE VERSION of map
Scientific Articles
2004 - Reemerging Leptospirosis, California
2006 - Canine Leptospirosis 2002-2004
