The Haemaphysalis longicornis tick can carry the virus that causes severe fever with thrombocytopenia syndrome (SFTS). (Photo: Shutterstock)
A veterinary research group at OSU has confirmed the existence of an exotic tick that has been previously reported in New Jersey, Virginia, and West Virginia.
By Amanda Carrozza
Tick season is upon us, so it may come as no surprise that a research group at Oklahoma State University’s (OSU) Center for Veterinary Health Sciences has confirmed the existence of an exotic species of tick in the United States.
Found on a dog in Alabama, the parasite has been classified as a nymphal longhorned tick or bush tick, Haemaphysalis longicornis, and was discovered through a national tick surveillance project being conducted by the OSU team, led by Susan Little, DVM, PhD, DACVM (parasitology). The lab confirmed the morphologic identification by sequencing and reported the finding to the US Department of Agriculture.
“We knew to be on the lookout for this tick given recent reports in New Jersey, Virginia, and West Virginia,” said Dr. Little. “We are very glad we were able to assist on efforts to understand the current distribution of this new species.”
H longicornis originated in East Asia and invasive populations have been established in Australia, New Zealand, and several Pacific Islands—and perhaps now, the eastern United States. Earlier this year, the Journal of Medical Entomology published a report of these ticks infesting sheep in Hunterdon County, New Jersey in summer 2017. All life stages were found on the sheep, which had no history of traveling outside of the country. The New Jersey incident was believed to be the first established population of the species ever documented in the United States.
According to a related report in Entomology Today, H longicornis is a unique species of tick because of its capacity for parthenogenesis—reproduction without fertilization, in which females produce offspring that are nearly clones of themselves. It’s this trait that gives the species the ability to infest areas in a short period of time. In fact, among the 27 adults, 41 nymphs, and 1058 larvae collected in New Jersey, just 1 specimen was male.
H longicornis readily feed on cattle, but they are also known to attach to small ruminants, horses, dogs, cats, people, and several common wildlife species as well.
Surveillance is currently ongoing to learn more about where the species is located within the country and if it may be carrying any disease. The Centers for Disease Control and Prevention reports that in China, H longicornis has been suspected to be the vector of severe fever with thrombocytopenia syndrome virus. None of the ticks collected in New Jersey were found to be carrying disease, according to the New Jersey Division of Fish and Wildlife.
In other parts of the world, most modern tick preventives are effective against this species.
In a Related Story from Forbes
New Jersey Is Dealing With A Tick Species That Is New To America
by Bruce Y. Lee
Looks like a bunch of New Jersey residents survived the winter. But that is not really good news.
On Friday, the New Jersey Department of Agriculture announced the latest follow-up to what was described in a February 2018 publication in the Journal of Medical Entomology. The publication detailed an “uptick” in the New Jersey population that occurred last Summer. On August 1 , 2017, after shearing a 12-year-old Icelandic sheep named Hannah, a farmer went to the Hunterdon County Health Office with some new companions. Thousands of them, in fact. No, she didn’t form a flash mob. Instead, she had thousands of ticks covering her body. Yes, you can say ewe and ewwwww.
What was particularly disturbing about this situation (besides the fact that she was covered with thousands of ticks) was that this was a tick species not typically found in the United States. And it certainly wasn’t one of the 5 tick species that were known to be present in New Jersey, which, of course, you know are Ixodes scapularis, Amblyomma americanum, Dermacentor variabilis, Rhipicephalus sanguineus, and Ixodes cookei.
Instead, it was the Haemaphysalis longicornis species, otherwise known as the East Asian or Longhorned tick. This tick is usually found in East Asia (Russia, Japan, China, and Korea), New Zealand, parts of Australia, and several Pacific islands (New Caledonia, Fiji, Western Samoa, Tonga, Vanuatu). Hannah the sheep had not traveled internationally or even much outside Hunterdon County (presumably officials had checked the sheep’s passport, frequent flier miles, and Instagram account). Therefore, officials are still not sure how the tick entered the United States.
Here’s the description of what officials found when they investigated the Hunterdon property in early October:
The ticks in the paddock were so numerous that they crawled on investigators’ pants soon after setting foot inside. The sheep was supporting hundreds of ticks, including all three active life stages (larva, nymph, adult). Although ticks were concentrated on the sheep’s ears and face, engorged ticks of all stages were readily found all over its body, including areas beneath the animal’s thick coat. In contrast, questing ticks recovered from the field were almost exclusively larvae.
Again, ewe and ewwwww. By the way, “questing” doesn’t mean looking for the Holy Grail or traveling to Mordor to destroy a ring. “Questing” is a position that ticks assume when they are waiting to climb on a person or animal. This was the first time that this tick was found to be breeding in the U.S. Oh, and by the way, these ticks don’t need to have sex to multiply.
Having a new tick on the block is concerning. Rarely, do you hear anyone say, “ticks, oh good.” That’s because ticks suck, literally and figuratively. A tick can attach to your skin, insert its feeding tube into your skin, use its saliva to numb the area so that you can’t feel it, and then suck your blood for days. This can occur if you are a human or another mammal, depending on the species of tick. During feeding, a tick may pick up or deposit various microbes. Thus, ticks could serve as an Uber for disease-causing microbes between humans and other mammals.
As described in this publication in the journal Emerging Infectious Diseases (note that you usually do not want to catch any disease that’s been featured in this journal), the Haemaphysalis longicornis tick has been spreading the virus that causes severe fever with thrombocytopenia syndrome (SFTS) in parts of China. SFTS is what it sounds like, a disease that results in fever and low platelets, so that you start bleeding. Oh, and you never want to catch a disease with the word “severe” in its name. Besides fever and low platelets, those infected with the SFTS virus can also develop gastrointestinal symptoms, low white blood cell counts, and elevated liver enzymes. Up to a 30% of people with SFTS die (usually from multi-organ failure) as indicated by this publication in the Journal of Virology.
The East Asian or Longhorned tick has also been known to spread Rickettsia japonica, which can cause Japanese spotted fever, and Theileria orientalis, which can cause theileriosis in cattle, and to carry other microbes such as Anaplasma, Ehrlichia, and Borrelia spp. Indeed, all of this should leave you ticked off. So far, health officials have not found the Longhorned ticks in New Jersey to be carrying any disease-causing microbes. But as they say, tick-tock, tick-tock, eventually they could.
As Chris Sheldon wrote for NJ.com, officials have tried to eliminate the ticks by washing the sheep with chemicals, cutting tall grass in the area, and monitoring the spread of the ticks. They were hoping that the ticks may not have survived the winter. However, the New Jersey Department of Agriculture announced on Friday that despite the cold winter, this new tick species is still hanging around. Indeed, New Jerseyans can be tough, and unfortunately these new New Jersey residents may be so as well.
