With the unexpectedly premature arrival of lone star ticks on Martha’s Vineyard, boards of health are considering what the future of mitigation and prevention of vector-borne illnesses might look like.
Richard Johnson, Island entomologist and current head of the Martha’s Vineyard tick-borne illness reduction initiative (Tick Program), was more than surprised to see lone star ticks emerging in droves in Aquinnah and on Chappaquiddick as early as mid-March.
“I usually don’t even start looking for ticks until this next week, but because I was getting so many calls about the lone star ticks, I went out and started looking,” Johnson said. “I found a lot of adult deer ticks, and I was completely shocked to find that in March, the lone star ticks were out on Chappy and in Aquinnah — I never would have dreamed it.”
Although Johnson said the jury is still out on how weather patterns affect ticks specifically, it has to be warm enough for the cold-blooded creatures to come out of hibernation.
While adult deer ticks are tough enough to come out in the colder months of February and early March, Johnson said, it wasn’t until this year that he saw the lone star population bloom so early on.
Johnson, who is looking at retiring soon, said he wants to pass the torch to someone who has the professional knowledge and experience to support all Island boards of health with combating tick- and other vector-borne illnesses.
“It’s time for a new, young person with energy and enthusiasm to take over. I certainly won’t drop it entirely; this program is too important to me. I will still stay involved in some way and at some level,” Johnson said.
He stressed that tick-borne illness prevention happens at three different levels: the personal level, the home level, and the neighborhood and Islandwide level.
For people on the Island, especially those who live near heavily wooded areas, Johnson noted that wearing permethrin-treated clothing or using permethrin spray can deter ticks. Wearing white socks over your pant leg also allows for ticks to be easily spotted.
At home, reducing the opportunity for ticks to move into your yard, and keeping deer away, are two essential steps in preventing tick-borne disease, Johnson said. “Clean up all the leaf litter and pine needles out of your yard. Maybe cut back some branches, and let a little more sunshine in to dry everything out. Ticks need moisture and humidity, that’s why they are down in the pine needles,” he said. He added that folks should carefully determine where they store their firewood, as the mice that live in wood piles can harbor ticks.
The third level is the Islandwide level, which Johnson said will require a holistic effort that addresses the problem at its core. In his opinion, the only way the Vineyard can reduce the tick population in the long run is to reduce the deer population.
With all three life stages of lone star tick relying on deer for sustenance and an area to reproduce, Johnson said, the number of deer would have to be significantly reduced in order to make a lasting impact on ticks.
With an estimated population density of 40 deer per square mile on Martha’s Vineyard, that number would have to be nearly cut in half in order to see what some modeling suggests would result in a decrease in ticks.
Based on other studies and modeling, Johnson said, reducing the concentration to about eight to 10 deer per square mile would start to interrupt the tick reproduction cycle.
For more than a decade, Johnson has conducted yard surveys and mitigation efforts, done extensive field research, and worked with the boards of health to try and create a bird’s-eye view of the issue.
For local health officials, the Tick Program is an exemplary model of how crosstown collaboration with a designated specialist assisting Islandwide can make a big difference in how mitigation efforts function.
Now that Johnson is eyeing retirement, boards of health have secured funding to plan and eventually implement an Islandwide approach to vector-borne illness, with a designated specialist who isn’t just under the direction of a single town.
“We are trying to now formalize a presence and a professional level staffing that the towns share for this type of work,” said Chilmark health agent Marina Lent.
She noted that most of these environmental health issues are cross-border, including diseases spread from ticks, mosquitoes, and other animals.
“We have been very fortunate on Martha’s Vineyard with human cases of West Nile and Eastern equine encephalitis, but we know it is going in the wrong direction — it is going to get worse. Another one is rabies,” Lent said. “That is going to set public health on its head when that happens. When that first rabid raccoon is identified, we will be in deep as far as having to mount a serious response. This position would keep that issue on the radar, and prepare us for it so that when all of us agents jump to our feet, we know what we are jumping into.”
Edgartown health agent Matt Poole said the Tick Program model, with Johnson as the point person for any tick mitigation or disease prevention initiatives for all the Island towns, is the perfect representation of a working relationship that utilizes the knowledge and skills of a designated specialist.
He noted that human health — particularly transmissible diseases — should be an Islandwide concern. “Human health impacts absolutely don’t respect town borders. So what we are looking at is having specialists who can look at specific issues like food safety, housing quality, and back to the vector-borne diseases, instead of having a generalist in each town,” Poole said. “There is plenty that we could use help on.”