Just when you thought that tick-control products kept us up to date, on July 25 the National Institutes of Health issued a warning about an expected increase in cases of tick-borne diseases. Gosh, I hate it when that happens.
The agency cites a commentary by leading scientists from the National Institute of Allergy and Infectious Diseases (NIAID, part of the National Institutes of Health) reported in the prestigious New England Journal of Medicine.
The authors of the comment say that there are likely many factors that have contributed to the rise of tick-borne diseases in the last decade, but larger tick densities and their growing geographic reach are two major ones.
For example, the tick responsible for most Lyme disease here in the northeast (commonly known as deer tick or black-leg tick, but back on the block we called it Ixodes scapularis) was discovered in nearly 50 percent more districts 2015, as already reported in 1996.
You may recall from the High School Science Class that Borrelia burgdorferi is the spirochete responsible for most of the Lyme disease in North America. It is borne by hard ticks like Ixodes scapularis, which usually feed on mammals from mice to deer, but eagerly take a meal from your dog or cat (or from you).
The United States Centers for Disease Control and Prevention (CDC) report about 30,000 cases of Lyme disease each year in the United States, but suspect that the actual number is 10 times greater.
This under-assessment, according to the article, is the result of two things: the limitations of current surveillance of tick-borne diseases, as well as current diagnostics, which in some cases may be inaccurate and fail to detect new tick-borne pathogens.
The researchers are currently investigating new, innovative diagnostics with various platforms that could bring clinical benefits in the future, but in the meantime, the cavalry has arrived.
On July 18, 2018, the US Food and Drug Administration approved NexGard to prevent infections that cause Lyme disease in dogs. NexGard was approved in 2013 to treat and prevent flea infestation and to kill black-legged ticks, American Dog ticks, Lone Star ticks and Brown Dog ticks.
However, Merial presented data in its adjunctive application that measured the transmission of Borrelia burgdorferi to dogs bitten by infected ticks and demonstrated that transmission was prevented by killing the ticks.
Incidentally, Lyme disease can cause serious illness in dogs and humans. In dogs, the disease can cause fever, loss of appetite, lameness, joint swelling and lethargy. In some cases, it can lead to acute kidney disease.
In humans, it starts like the flu: fever, chills, headache, fatigue, muscle and joint pains and swollen lymph nodes. As it progresses: severe headache, neck stiffness, arthritis with severe joint pain and swelling, drooping on one or both sides of the face, irregular heartbeat, inflammation of the brain and spinal cord and sharp pains, numbness or tingling in the hand or feet.
A "bullseye rash" is often seen in people with Lyme disease, but it can not occur in dogs. Prevention is the key. Talk to your veterinarian about pet products and discuss farm products with people in the gardening business.
Bob Bamberg has been in the pet industry for three decades and writes about pets, livestock and wildlife. It can be reached at firstname.lastname@example.org.