Leptospirosis... A Few Insights
It seems like Lepto is everywhere! I wanted wanted to give you all the answers you need to know to help field the onslaught of calls about this infection, but as I considered the topic, I found I did not have a lot of firm answers. However, I do have some insights that might help as you and your staff face anxious clients.
Who should we be testing? Any dog with unexpected liver or kidney enzyme elevations that feels ill for ANY reason should be tested, particularly those with a fever, muscle pain, lesions consistent with vasculitis, and/or low platelet counts.
How should we be testing? I prefer serologic tests done through microscopic agglutination (MAT), ideally two sets done two to four weeks apart to demonstrate a fourfold rise in titer. I like this test because results are typically obtained in a few days and can give us an ideal of the serovar involved. More rapid tests like SNAP are available but may not be as sensitive or specific. In addition, if your patient has been recently vaccinated, interpretation can be difficult, and positive levels can indicate exposure while negative results can be seen early in the course of disease. PCR testing is also a good method, but results take more time, and false negatives can occur in pets on antibiotics. Likely, we should be doing both MAT and PCR tests for the most complete medical information.
How should we treat these patients? The most common protocol is four weeks of amoxicillin followed by four weeks of doxycycline. Traditionally, it has been thought that patients are not infectious after 48 hours of treatment, but newer information may indicate a longer period of active shedding, possible for several months after treatment starts.
What precautions should staff take? Wear gloves when handling a patient or specimens from a patient suspected of having leptospirosis. Contain all urine as much as possible. Use catheters, and gurney patients around the hospital when feasible to prevent contamination. Have suspect patients urinate in a single area that can be disinfected regularly. Clean all potentially contaminated areas with bleach diluted 1:10.
What precautions should owners take? They should also wear gloves when cleaning up urine, feces, or vomit. They should wash their hands after interacting with pets that are suspected of or confirmed as having leptospirosis. Children and immune-compromised family members should not be in contact with pets until they are no longer shedding. These pets should not be boarded, if possible, and should not go to dog parks, pet stores, or other areas where pets congregate regularly.
Should we vaccinate? Vaccination against leptospirosis should be considered for each of your patients on an individual basis. I recommend using a vaccine that contains four serovars and prevents shedding of organisms. This is a conversation you need to have with each client about their pet's lifestyle and make an educated recommendation based on that discussion. Remember, leptospirosis does not discriminate based on size, so if you have a toy breed dog who goes to dog parks, visits dog shows, or likes to hike and drink from streams, it may be at risk
For More Information
Center for Disease Control (CDC) at: https://www.cdc.gov/leptospirosis