An invasive tick species in the United States
If you’ve been following the news lately, there’s been a lot of discussion about a tick species recently introduced into the United States, the longhorned tick (Haemaphysalis longicornis).
This tick is native to eastern Asia and has successfully invaded both Australia and New Zealand. Last November, it was identified on sheep on a New Jersey farm, and has subsequently been detected in several other states in 2018. Based on re-examination of past samples, it is now believed to have been in the USA since at least 2010.
To date, this tick has not been detected in Canada.
You are probably wondering: (1) How did this happen? (2) What is being done in Canada? (3) What are the risks? (4) How do I protect myself and my pet? Let’s take a few minutes to talk about these questions.
It is not known exactly how this tick ended up in the United States. And we may never know. However, with extensive movement of people and animals around the globe, international travel is a highly plausible explanation. Rapid spread of this tick is possible in part due to the unique reproductive abilities of this species. Female ticks lay eggs without the need to mate with a male. This means that under the right conditions, one adult female can start a population on her own. These ticks thrive in grassy areas near forests and meadows.
In Canada, we know there is the potential for this tick to be introduced. In response, we are working with public health officials to monitor for this tick species. Programs like the Pet Tick Tracker are at the front lines of detecting changes in tick populations, and all of you play an important role in surveillance. Keep your tick submissions coming and be sure to include a photo or submit the actual tick whenever possible.
The longhorned tick is known predominately as a pest of livestock. It can cause large infestations on cattle, horses, sheep and goats. These infestations can be a burden to livestock species and in severe cases, lead to anemia, decreased growth, poor production and even death. It will also feed on other mammals, including dogs, cats and people. No pathogens have been detected in the ticks in the USA, but this tick is known to transmit several bacteria and viruses in Asia.
When thinking about protection, our messaging does not change for this tick species. Cover up when you are in tick habitat (in this case, long grasses) and use an insect repellent that contains DEET or icaridin. Use a good tick preventative on your dogs and cats, which your veterinarian can help you with (although no products are licensed for this tick in the USA or Canada, recent information from the USDA indicates that current veterinary tick preventatives should provide coverage). And last, but certainly not least, do a thorough tick check on yourself, your pets and your family every day.
For more information, the USDA has put together a helpful fact sheet.
We will keep you posted on any developments on this tick in the future.
-KMC