By Dr. Becker
I ran across a study recently that actually serves as a warning for humans, but applies to pets as well, so I thought I should bring the information here and share it with you.
Blacklegged Ticks in Certain Areas of the U.S. Carry Multiple Pathogens
Scientists have learned that blacklegged ticks in some regions of the U.S. are carrying both Lyme disease and babesiosis,1 making their infection risk a potential double-whammy.
Researchers examined thousands of blacklegged ticks (deer ticks) from over 100 different sites in Duchess County, NY, an area with frequent reports of tick-borne illness. They also sampled ticks that feed on different species of wildlife, including birds, rodents, opossums, and raccoons.
The researchers took DNA samples from each tick and discovered the presence of several different pathogens. About 30 percent of the ticks harbored the Lyme bacteria, and about a third of that 30 percent also carried a second pathogen. Around 7 percent of ticks carried both Lyme disease and babesiosis.
The researchers then crunched the numbers and determined that the risk of co-infection was greater than they originally anticipated.
Pets and Humans Living in Tick-Infested Areas Are Vulnerable to Two or Three Diseases from a Single Tick Bite
Ticks pick up pathogens from infected wildlife. In the case of Lyme and babesiosis, mice and chipmunks are the primary reservoirs. Ticks that attach to these animals are much more likely to be co-infected, according to lead study author Michelle Hersh of Sarah Lawrence College.
Some of the ticks sampled by the researchers were infected with three pathogens – Lyme, babesiosis, and anaplasmosis. And similar to the risk of co-infection with the first two, the risk of a triple infection was twice as likely as the researchers expected.
"Mice and other small mammals are often particularly abundant in habitats that have been fragmented or degraded by human activity," said study co-author Richard Ostfeld of the Cary Institute of Ecosystem Studies. "That means these patterns of co-infection might get worse through time as humans continue to impact forest ecosystems."
These are the same concerns expressed by veterinarian and bioethicist Dr. Michael W. Fox in his article "Lyme Disease, Wildlife Management and Public Health," as well as his compelling article on the One Health perspective on Lyme disease.
The study authors warn that people living in tick-infested areas of the country, including the northeast, mid-Atlantic, and upper Midwest, are potentially vulnerable to exposure to two or three diseases from a single tick bite. Both the public and health care providers need to be on the lookout for the possibility of multiple infections.
I would offer the same warning for pets living in those areas as well. Fortunately, the SNAP 4Dx Plus and the Accuplex4 tests screen for heartworm, Lyme disease, and two strains each of ehrlichia and anaplasma, but they don't pick up Babesia. So I would recommend that pets living in the tick-infested areas noted above who test positive on the SNAP 4Dx Plus or the Accuplex4 also be screened for Babesia exposure. The best way to detect exposure to this parasite is with a PCR (polymerase chain reaction) test that checks for the presence of Babesia DNA. While only certain laboratories run this type of testing, it is really the best method for confirming a Babesia infection.
My Recommendations for Preventing a Tick-borne Infection in Your Pet
- When flea and tick season arrives, check for ticks daily, and don't overlook areas of your pet's body where ticks can hide, like between the toes, the underside of the toes, in the earflaps and around the tail base. If you're ever unsure whether you're looking at a tick or some other bump on your dog, get out a magnifying glass and look for the telltale sign of a tick – legs.
- Research demonstrates that ticks must be attached to your dog for at least 24 hours in order for most disease-causing bacteria to be transmitted from the tick to your pet. That's why daily tick checks and removing ticks immediately is a huge part of reducing your dog's risk of acquiring a tick-borne disease. If you prefer to err on the side of extreme caution, you can check your pet for ticks each time he may have been exposed (in other words, each time he visits an area outdoors that may harbor ticks). This is hands-down the safest and entirely non-toxic method of tick prevention.
- If you find a tick on your dog, be sure to remove it correctly. Don't use your bare hands. People can become infected by handling or crushing an infected tick. Wear gloves, or even better, use a tick-removing tool.
- Grasp the tick very close to your pet's skin with a tick removal tool or a pair of tweezers. Carefully pull the tick's body away from the skin. Once it's off, flush it down the toilet. Then disinfect your dog's skin with soapy water or diluted povidone iodine (Betadine). Disinfect the area really well and monitor it for the next few days. If you notice any irritation or inflammation of the skin, you should contact your veterinarian.
- Have your dog tested for tick-borne diseases about three to four weeks after removing a tick. The type of test to ask your vet for is the SNAP 4Dx or Accuplex4 test, which is a screening blood test. If you don't have the 4Dx or Accuplex test done, you'll want to watch your dog closely for several months for any signs of loss of appetite, lethargy, changes in gait, fever, intermittent limping – all the symptoms of potential tick-borne disease. And keep in mind that waiting until a dog exhibits symptoms isn't the most proactive approach.
Checking your dog externally for ticks and having his blood checked regularly (I recommend every 6 months) for silent infections is the very best approach to keeping your pet safe from potentially devastating tick-borne diseases.