Tick paralysis is caused by a neurotoxin produced by egg-engorged female ticks, who transmit the toxin from their salivary glands to the dog during feeding. The production (and transmission) of the toxin is greatest when the tick has been attached to and feeding from the dog between five and seven days. Five species of North American ticks produce the neurotoxin: the blacklegged tick (a.k.a. the deer tick), American dog tick, Rocky Mountain wood tick, the Lone Star tick, and the Gulf Coast tick. Most North American cases occur between April and June, when the ticks are at their peak reproductive activity.
Lately, it seems like new flea and tick control products have been popping up left and right. I suspect this is due to some of the original patents running out. When a patent expires, other companies can create generic versions of the same product, usually for less money. This inspires the original companies to create new products that they can patent anew. In some cases, new products are introduced because fleas and ticks may be developing resistance to the older products, lowering their efficacy. Most new products, including all those introduced this year, are just new combinations of older ingredients. Here’s a rundown on these new options.
Researchers at Cornell University's Animal Health Diagnostic Center have developed a new test for Lyme disease in dogs. Available as of June 15, the Lyme multiplex assay is capable of distinguishing between infection and vaccination when vaccination history is available, and between early and chronic disease stages, from a single blood sample. Borrelia burgdorferi, the bacteria that cause Lyme disease, migrate by way of the tissues to the joints, nervous system, and organs, causing fever, pain, lameness, and sometimes kidney failure (Lyme nephropathy). By the time these clinical signs show up, the infection may have been present 6 to 8 weeks or longer.
Pfizer has announced plans to discontinue manufacture and sale of its flea and tick control product, ProMeris. Orders will continue to be filled until September 20, 2011. ProMeris was introduced in the fall of 2007, and touted as the first topical product to use metaflumizone. Pfizer gained control of ProMeris when it acquired Wyeth/Fort Dodge Animal Health in 2009. Pfizer is also the maker of Revolution, used to control fleas and one species of ticks, along with heartworm, ear mites, and sarcoptic mange.
Given the potential duration and magnitude of a Lyme disease infection in your dog, we think it's pretty important to do something to protect your dog from ticks, especially in areas where cases of Lyme are common. This is one of the instances where you have to weigh all the factors against each other in this case, your dog's health and vulnerability, the risk of his exposure to ticks, the prevalence of Lyme in your area, and the tick-repelling and tick-killing products available to you to decide what you are going to do to protect your dog. It's not an easy equation; it's more of a complicated algorithm. Let's look at each of these areas and how they interact.
Lyme disease affects thousands of Americans and their dogs and horses each year. Named for Old Lyme, Connecticut, where it was discovered formally identified in the 1970s, Lyme is a regional disease, with 90 percent of its cases in New England and the Middle Atlantic states. The rest come from the upper Mississippi (Wisconsin and nearby states) and parts of California and Oregon. A few dogs and people with Lyme disease live elsewhere, but they are believed to have been infected during travel or, in some cases, by ticks from migrating birds. Veterinarians in the Northeast know Lyme disease well. Its symptoms are very noticeable in dogs