The Rhode Island Department of Environmental Management (DEM) is announcing that two exotic species of Asian and Eurasian ticks have been detected for the first time on Block Island. The ticks were discovered by Dr. Danielle M Tufts, then an associate research scientists at Columbia University, as part of a research program conducted by Dr. Maria Diuk-Wasser's research group on Block Island since 2010. It was confirmed by DNA and morphological characteristics that they are ticks not previously found in Rhode Island.
Dr. Tufts identified the tick species Haemaphysalis longicornis and Haemaphysalis punctata when studying ticks on Block Island this summer. Due to similarities with native ticks, these exotic ticks were initially thought to be native tick species but on further investigation were found to be exotic species. Dr. Tufts then looked through archive samples previously collected from Block Island from 2010 to 2020 and determined these species have been present on Block Island for many years. H. Longicornis, also called the Asian longhorned tick, was first detected in the United States in 2017 in New Jersey but when archived samples were reviewed in other states, it was determined that these ticks may have been in the country since at least 2010. The H. punctata species is native to Europe and has not been previously detected in a natural setting in North America (it has been detected on imported animals and animal products undergoing importation inspections).
The Asian longhorned tick is considered a serious threat to livestock in Australia and New Zealand, where it is invasive. It poses a risk to New England livestock because it can attach itself to various warm-blooded animals to feed. If too many ticks attach to one animal, the loss of blood can kill the animal. The ticks also can affect wildlife, hunters, and their dogs, and spread a variety of diseases. However, only one disease has been found in these ticks in the United States. Dark brown in color, the adult longhorned tick grows to the size of a pea when it is engorged with blood. The other life stages of the tick, such as larva and nymph, are very small and difficult to see with the naked eye. Click here for more information on the distribution of this tick in the United States.
H. punctata is sometimes known as the "red sheep tick" in its native range. The center of its distribution is the southern half of Europe, including England, and there are some established populations along North African coastal areas. The finding on Block Island is notable because this tick is not known to exist outside of its home range.
H. punctata is environmentally adaptable to a variety of climatic conditions and habitats and typically feeds on sheep, goats, and cattle. Various other species, however, also serve as host options with humans bitten only infrequently. Both species recently identified can transmit a variety of diseases to both humans and animals.
Tick-borne diseases, including those from ticks native to New England, also pose a hazard to people, livestock, and pets. Livestock farmers, hunters, and hikers are at higher risk. In addition to the risk of having the tick attach, hunters and hikers transport the tick from one location to another as they walk through wooded areas, grasses, and shrubs. To prevent the transfer of ticks to new sites, DEM recommends that hunters and hikers:
• Apply tick repellents to exposed skin and clothing.
• Spray permethrin-containing products on outer clothing, including shoes. Permethrin should not be used directly on skin.
• Check clothing and exposed skin prior to moving from one area to another.
• Wear light colored long-sleeved shirts and long pants.
• Conduct body checks immediately after returning from outdoor activities in tick-infested areas.
If ticks are found, remove them by using fine-tipped tweezers, wash the affected area with soap and water, and disinfect the bite site. To protect hunting dogs, hunters should check with their veterinarian about an appropriate topical or systemic tick-control treatment for their dog. Any ticks attached to dogs should be promptly and carefully removed following the same guidelines for tick removal from human skin.
For information on tick-borne diseases, visit http://health.ri.gov/ticks/. For information on DEM programs and initiatives, visit www.dem.ri.gov. Follow us on Facebook at www.facebook.com/RhodeIslandDEM or on Twitter (@RhodeIslandDEM) for timely updates.