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Leptospirosis should you Vaccinate????
1. Leptospira is shaped like a question mark and is a special type of bacterium called a spirochete.
When a Dog Becomes Infected

Dogs become infected by leptospires when abraded skin comes into contact with the urine of an infected host. The organisms quickly spread through the bloodstream leading to fever, joint pain, and general malaise which can last up to a week. The organism settles in the kidneys and begins to reproduce, leading to further inflammation and then kidney failure. Depending on the type of Leptospires involved, other organ failure (especially liver) can be expected as well. Make no mistake, leptospirosis is a life-threatening disease.
Typical symptoms: Fever, depression, loss of appetite, joint pain, nausea, excessive drinking, jaundice, excess bleeding brought on by low platelet count..
PEOPLE CAN BECOME INFECTED, TOO!
The Infection in Humans

The Centers for Disease Control and Prevention monitor leptospirosis cases in people, and it seems that one third come from contact with infected dogs and one third come from contact with rats (usually through field work). The same disease symptoms occur in humans as would be seen in a canine infection.
About the Organism

The species Leptospira interrogans has been classified into subtypes called SEROVARS Over 200 serovars have been named.
Testing

Blood testing to detect antibodies against Leptospira (microscopic agglutination testing) can be performed. While a value of 1:800 or higher is supportive of a positive diagnosis, confirmation is not made until a second antibody level (called a titer) is run between 2 and 4 weeks and shows a four-fold increase. Vaccination may interfere with testing since obviously the entire point of vaccination is to generate antibodies. If the dog has been vaccinated in the last 3 months, testing will be difficult to interpret; however, a single titer of 1:800 or higher against a serovar for which there is no vaccine is considered a positive result. The PCR test, which amplifies small amounts of DNA, would be an excellent test if vaccination has been recent but PCR testing is not available in most reference laboratories.
Urine may be submitted for what is called Dark-field Microscopy. In this test, a dark background may offset the paler Leptospires organisms rendering them visible. This sounds like a good way to make the diagnosis but the problems are:
1. The urine sample must be fresh and most animal hospitals do not have the capability to do dark field microscopy.
2. Leptospires are only shed in urine intermittently.
The kidney may be biopsied and special tissue stains may be used to detect Leptospires organisms. Obviously this is an invasive procedure.
Treatment

Fortunately, Leptospira is sensitive to penicillin, a readily available antibiotic. After penicillin has been used to stop Leptospires reproduction and limit bloodstream infection, tetracycline derivatives are used to clear leptospires from the kidneys. Since tetracyclines and penicillins are not a good concurrent combination, often a combination of a penicillin with a fluroquinolone type antibiotic (such as ) is used to cover both phases of the infection.
Intravenous fluids are crucial to support blood flow through the damaged kidneys so that recovery is possible. Any areas at home that have been contaminated with urine should be disinfected with an iodine based product and gloves should be worn in cleaning up any urine. Prognosis is guarded depending on the extent of organ damage.
What Constitutes a Moderate to Severe Toxin Build Up?
The parameters measured in the assessment of kidney function are called BUN (blood urea nitrogen - with normal levels around 25 mg/dl) and creatinine (normal levels less than 2.0 mg/dl). In the above study, the group termed mild to moderate had an initial BUN level ranging from 24 to 225 mg/dl and initial creatinine levels between 1.7 and 11.5 mg/dl. Again, 82% of these dogs survived with only traditional fluid therapy as can be performed in most veterinary practices. The moderate to severe group had initial BUN levels ranging from 97 to 365 mg/dl and initial creatinine levels ranging from 6.5-21.9 mg/dl. Obviously, there is some overlap.
VACCINATION REACTIONS ARE COMMON!
Vaccination Options

Vaccination against Leptospira is only available for the serovars called canicola, grippotyphosa, pomona and icterohaemorragiae. The vaccination is suggest to be given two to three times yearly. As a result of long standing use of this vaccine, it is hard to assess how important it is to vaccinate against leptospirosis. (As you might imagine, most recent outbreaks involve serovars for which vaccination does not exist.) Of all the sera in this basic vaccine, it seems to be the leptospirosis that is associated with hives, facial swelling, and even life-threatening vaccination reactions much more than any of the vaccine for Distemper, Parvo or Hepatitis. If there is any question of an animal having a vaccine reaction, leptospirosis vaccine should not be given.

Leptospirosis vaccine is considered an optional vaccine, to be used if the dog is at risk. If the animal lives on a farm, where there is a combination of rats, mice and stagnant water. An inner city dog that runs loose, and where the city has open drainage canals with stagnant water. The dog needs to be over 15 pounds because small dogs react more violently against the vaccine. Leptospirosis has 8 common serotypes in this country, each serovar needs to be in the vaccine to give adequate protection. The best vaccine available only carries 4 serovar; therefor you can cannot assure adequate protection with this vaccine. When Leptospirosis is combined in the D.H.L.P.P vaccine ( commonly referred to as the distemper shot ) this vaccine only carries two serovars. Leptospirosis vaccine is recommended to be given two to three times yearly to achieve adequate protection. Increasing the frequency of the vaccine increases the occurrence of severe allergic reactions, therefore making the vaccine more dangerous. Why then should we routinely vaccinate with a vaccine that has a high complication rate, gives poor protection or no protection at all against the organism.

Dr. Gary Schrader