Lone star tick population is growing


To the Editor:
The change in seasons also brings changes in the tick populations. As we enter September, we are seeing very few deer tick nymphs, and no adult deer ticks. The number of lone star nymphs and adults is also decreasing, although there are still plenty of lone star nymphs out and about. On the other hand, we are starting to see more lone star larvae, and expect their numbers to peak during September. The larvae are the tiny ticks that hang in clusters from grass and other low vegetation. When you encounter them, you generally get dozens to hundreds of tiny, pinhead-size ticks on your clothes and body.

Although they start low, around your knees and ankles, they move very quickly, and can rapidly spread to your upper legs and body. Although lone star larvae are not believed to transmit diseases, they do cause severe itching that can last for weeks. It is not clear whether they can cause the red meat allergy, but it seems unlikely since they have not fed yet, and therefore should not have picked up the alpha gal carbohydrate.

Lone star ticks are often associated with Aquinnah, the west end of Chilmark, and Chappaquiddick, and indeed that is where they are most numerous. However, they are becoming increasingly common in Edgartown, West Tisbury, and the rest of Chilmark. In addition, we are now finding lone star ticks in Oak Bluffs and Tisbury, usually in low numbers, but not always. For example, we found 20 lone star ticks at the Land Bank’s Pecoy Point Preserve this summer. I expect that in three to five years, lone star ticks will be common in all six Island towns.

The other surprise this summer is that for the first time, we found lone star ticks in people’s lawns. In all three cases, the lawn grass was higher than 4 inches; shorter grass still seems to be too hot and dry for them to thrive. Nonetheless, this is a disturbing trend, with serious implications for homeowners on the Vineyard. 

Protecting yourself from lone star larvae is similar to protecting yourself from the nymphs. The best protection is to wear long pants treated with permethrin tucked into socks that are also permethrin-treated. You can buy the spray and treat your own clothes (see video on our website, mvboh.com, showing how to do this), buy clothing pretreated with permethrin, or send your clothes to Insect Shield, and they will treat them for you.

If you don’t want to wear socks and long pants or permethrin-treated clothing, the next best thing is to spray your feet, ankles, and lower legs with either 30 percent DEET, such as Deep Woods Off or Picaridin. Since Picaridin’s active ingredient is based on a compound isolated from black pepper, some people prefer it to DEET. Picaridin can also be sprayed on your shoes and clothing. For more information, please refer to our website, or email me at ticksmv@gmail.com.

Richard Johnson, director
MV Tick program