Recently I attended a lecture presented by Dr. Susan Little, a veterinary parasitologist from Oklahoma State University that focused on ticks and tick-borne illness. She spoke of the deer tick and the American dog tick, two species commonly found in Ontario, but she also spoke of new and emerging tick species: Rhipicephalus sanguineus the brown dog tick and Amblomma americanum the lone start tick.
The brown dog tick usually found in the southern United States is unique in its ability to live and reproduce indoors. Ticks typically do not infest a house or kennel but in the case of the brown dog tick all three life stages (larva, nymph and adult) can survive indoors. An infestation can be difficult to eradicate as these ticks can survive for long periods of time without feeding from a host. Home infestations can take several months and multiple professional insecticide treatments. This tick is found more commonly in northern locations including Ontario. There has been a rise in part due to adoption or movement of dogs from the Southern US and the Caribbean to Ontario. Fortunately, this is easily avoided with proper treatment of dogs travelling from these areas. The brown dog tick does not transmit Lyme disease but can transmit Ehrilichia canis and Rocky mountain spotted fever causing, bleeding abnormalities, fever, lethargy and neurologic disease which can be life threatening in some cases.
The other emerging tick species is the lone star tick. This tick gets it name from a distinct white spot found on its body and from its natural home in the southern United States. This tick can now be found throughout the eastern U.S. and as far north as Wisconsin. Very recently this tick has also been found in Ontario. This is of concern as the lone star tick also transmits disease such as Ehrlichiosis which until recently was not found in Ontario unless the dog had travelled out of the province. This tick can also transmit Ehrlichia chaffeensis, the agent causing human monocytic ehrlichiosis and Cytauxzoon felis which causes a potentially fatal disease in cats. It is thought this tick is making its home further north due to the warming climate and by dropping off migrating birds.
In response to the rise in ticks the veterinary industry has brought several new tick prevention products to the market with more coming. Every dog owner should have a discussion with their veterinarian to determine the right tick prevention plan for them.
Written by: Dr. Dana Cini, DVM