Disease
Fact Sheet Series:
What is leptospirosis and what are its symptoms?
Leptospirosis is a zoonotic (transmitted from animals to humans)
disease of worldwide distribution that is quite uncommon in Wisconsin. It
is caused by several strains of a bacterium called Leptospira. Illness
can range from mild to severe. The illness is often characterized by
the abrupt onset of fever, chills, myalgias, and headache and may include
conjunctivitis, abdominal pain, vomiting, diarrhea, and skin rashes. Less
frequently, it can result in meningitis, liver and kidney dysfunction,
pulmonary involvement, and mental confusion. Severe cases occur more
commonly in older persons and can result in death.
How is it spread?
Many species of wild and domestic animals (including dogs, cattle,
horses, swine, rodents, swine, raccoons, and deer) are susceptible to
leptospirosis and can excrete the bacteria in their urine. Their urine can
then contaminate water, moist soil, or vegetation with the Leptospira
bacterium. Humans can acquire the infection if this contaminated material
contacts abraded skin, mucous membranes, or is ingested. Because infected
humans can also pass the bacterium in their urine, person-to-person
transmission is possible but rarely occurs.
Who is at risk of contracting leptospirosis?
Although all persons are susceptible, this uncommon infection occurs
mainly in persons whose occupation brings them into contact with animals
or with material contaminated with animal urine. Farmers, veterinarians,
slaughterhouse workers, sewer workers, and miners are at greater risk of
exposure. Although rare, exposures can also occur during recreational
activities such as camping or swimming, when there may be contact with or
ingestion of contaminated water. Leptospirosis occurs most often in the
summer and in warm climates.
How soon after exposure do symptoms appear?
Symptoms usually appear 5 to 14 days after exposure, with a range of 2
to 30 days.
How is leptospirosis diagnosed?
The diagnosis can be made by culturing the Leptospira bacterium
from body fluids (first seven days), from the cerebrospinal fluid (days
four to ten), and from urine (after the 10th day) following
symptom onset using special media. Diagnosis can also be made by detection
of rising antibody titers in specific serologic tests such as the
microscopic agglutination test (MAT). A newly developed ELIZA test which
detects IgM antibody is being evaluated at CDC and may have greater
sensitivity early in infection than other test methods. Because of
non-specific signs and symptoms during early infection, leptospirosis is
frequently not considered as a diagnosis until later in illness and can
compromise outbreak recognition and disease control.
What is the treatment for leptospirosis?
Mild infections can be treated with oral doxycycline while more severe
infections generally require intravenous penicillin. Prompt specific
treatment, as early in the illness as possible, is essential. Some
severely ill patients may require kidney dialysis.
If someone has had leptospirosis previously, can they
become reinfected?
Once a person has leptospirosis, they will be immune to another
infection with that same strain of Leptospira. However, infection
can occur with a different strain and illness may again result.
What can be done to prevent the spread of
leptospirosis?
For person in high-risk occupations, the use of protective clothing,
boots, and gloves will minimize exposure. Similar protection should also
be worn when disposing of dead animals and when gutting (cleaning) your
animals or livestock. Recognizing and avoiding potentially contaminated
water and soil during recreational activities, and rodent control in areas
where humans and domestic animals live can also reduce the risk of
exposure. Avoid swimming or wading in freshwater streams, ponds, or lakes
with open cuts or sores. Avoid intake of water in the mouth when swimming
in freshwater streams, ponds, or lakes. Do not drink stream, pond or lake
water without boiling, filtering or chemical treatment. Drain areas that
have stagnant or, standing water.
For more information, contact your
Local
Public Health Department
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Last Revised: March 20, 2008
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