The ticks are awful this year. As usual, everyone is worried about Lyme (rightly so…), but many people are unaware or forgetful of the fact that there are other diseases passed by ticks that we need to worry about. So, from now through the Fall, I will be talking about some of the more common ones that we worry about in New England when presented with a sick patient. The first is Anaplasma.
There are two species of Anaplasma that we worry about in pets: Anaplasma platys and Anaplasma phagocytophilum. While different species, they behave somewhat similarly and are caught the same way. Like Lyme disease, Anaplasma is carried by the blacklegged, or Deer, tick. These are the tiny red ones with the dark black legs. In Lyme disease, it takes a long time for the bacteria to start making its way into the patient once the tick starts feeding. So, most tick preventives can do a pretty good job of preventing Lyme. Anaplasma starts working its way into the patient in under 2 hours. So, no preventive has been 100% effective at keeping this bugger down. That said, some products are better than others. The long-acting pills and collars seem to do the worst. Discuss with your veterinarian which products they prefer for speed and effectiveness.
Once in the body, it can actually reproduce for quite a while without making the dog sick. Depending on the species, it can mostly attack either white blood cells (which create body’s response to infection) or the platelets (the cells needed to control bleeding). As the infection worsens over time, dogs will start to show signs similar to Lyme disease: fever, lethargy, and joint swelling. If caught early, we can usually treat them with antibiotics. If not caught, it can progress. The most common and scary progression of the disease is massive internal bleeding.
We screen for Anaplasma by looking for antibodies: the body’s response to exposure to the bacteria. We obviously would prefer to catch this before a dog becomes sick, so we screen for it annually. We typically do this before major vaccines are due. The reason for this is that it has been theorized (and anecdotally supported) that this is one of the diseases that was actually causing what we used to think were vaccine reactions. Basically, we would give a vaccine and, some weeks later, dogs would have sicknesses similar to those caused by Anaplasma. What may have been happening in these dogs is that they were carrying Anaplasma at the time of their shots and the vaccination stimulated their immune system to the point where the body recognized the disease. The sudden, robust response then causes major sickness in the dogs as its own body destroys the cells carrying the bacteria at a rate faster than the body can replace them.
So, when dogs are positive, we will typically hold off on vaccines until lab work is run. This annoys some people with the typical response being “But they’re not acting sick…!”. We get that, and we want to keep it that way. Luckily, the blood work is nothing major. It is literally the standard lab work that is recommended annually anyway. Most dogs are fine and can come back in the near future for their shots. If not, the treatment provided can typically clear the disease and prevent expensive stays in the hospital.