Asian tick able to clone itself may spread quickly in US, study reveals

A species of tick, that until recently was mainly found in China, Japan, Korea and Southeast Russia, is now present in 9 US states, according to new research.  

A nymph and adult female longhorn tick. Source: CDC

A nymph and adult female longhorn tick. Source: CDC

Scientists believe the Asian longhorned tick, which has also been identified in parts of Australia, New Zealand and the Pacific Islands, first invaded the US years ago.

The first established Asian longhorn tick population was discovered in New Jersey in 2017. Detections in Virginia, West Virginia, Pennsylvania, North Carolina and Arkansas then followed. 

New research - published in the Journal of Medical Entomology - indicates the tick may soon occupy a large area of eastern North America, and possibly coastal regions of the Pacific Northwest. 

The tick can bite and use any warm-blooded mammals as its host for a meal, meaning humans, pets, farm animals and wild life are all fair game. 

Although capable of carrying and transmitting infectious diseases, at the time of the study’s publication no cases of illness in humans or animals had been reported. 

The longhorn tick in woodland. Source: Mother Nature Network

The longhorn tick in woodland. Source: Mother Nature Network

Due to the ticks prevalence in differing geographical locations, Rochlin believes the tick has been present in the United States for a number of years. 

Source: science alert

Source: science alert

For his latest study, which anticipates the tick will gain further ground in the US, he compared climate data from Asia, Australia and New Zealand where the tick is already established. He then matched this with climate reports from North America. This modelling approach was then used to predict the possible range of the Longhorn tick in North America.

There is a good chance for this tick to become very widely distributed in North America.
— llia Rochlin, an entomologist and lead author of the study.

The Asian longhorned tick

  • Can effectively “clone itself”. It is parthenogenetic meaning females can create eggs using a full set of the mother’s DNA. These develop into adults without ever needing the DNA of a male. It is one of a handful of the 700 “hard” ticks to do this

  • This unusual reproductive quality enables it to cause massive infestations of its hosts, such as livestock or dogs

  • It is capable of transmitting infectious diseases and health conditions such as severe fever with thrombocytopenia syndrome (l) as well as Lyme disease, ehrlichiosis and anaplasmosis

Putting it in perspective

At the time of the report, there had been few instances of this tick feeding on humans. (As of March 2019, no harmful germs had been found in the ticks collected in the US although research is ongoing). Experts recognised that although the tick was present, it was unlikely to grow rapidly across the north east or eastern part of the US quickly. The official advice? Be cautious but not alarmed. Be tick aware and protect yourself effectively against bites. 

The best defence?


The official advice is to be diligent about protecting yourself and your family against tick bites. Exercising good tick bite prevention means you can continue to enjoy all the great outdoors has to offer.

Remember to take all the usual tick bite precautions such as:

Source: Lyme Disease UK

Source: Lyme Disease UK

  • carrying a tick kit like the one mentioned above

  • avoiding areas of dense undergrowth 

  • wearing effective insect repellent

  • wearing long sleeved tops and tucking trousers into socks

  • carry out a thorough tick check on yourself, your family and pets once you are back home 

  • put any clothes through a warm cycle in the dryer to kill any ticks who may have hitched a ride home

  • if you do find a tick, practice safe tick removal

  • if you begin to feel unwell following a tick bite, seek medical advice