Mosquito magnets, dumping kiddie pools, and staying indoors at dusk were some of the suggestions residents brought to the Board of Health’s vector-borne illness roundtable discussion on Feb. 25.
About a dozen residents came to the meeting prepared to take swats at the BOH warrant article that seeks funding to join the Central Massachusetts Mosquito Control Project (CMMCP). Tim Deschamps, Executive Director of CMMCP, explained the program and then responded to a variety of questions, mostly about the program’s policy of spraying by resident request. BOH Chairman Tom Philippou clarified the board’s position. “We’re not saying that this warrant article is going to be the solution,” said Philippou. “But we can’t keep our heads in the sand and hope that the mosquitoes are going to fly over and bypass Harvard. We need to start the conversation.”
Split BOH wants town to join program
The warrant article submitted by the BOH asks the town to vote on becoming a member of CMMCP for a minimum of three years. The program would cost Harvard $55,000 per year. For that, the town would get all the services listed in the sidebar. At their meeting this week, the Board of Selectmen voted not to recommend the article (see report on page 7).
What follows is a sample of the questions posed at the meeting. All were addressed to Deschamps by residents, unless otherwise noted. Responses, unless otherwise noted, are from Deschamps. Some questions and answers have been shortened in the interest of space.
Q: What recourse would I have if my neighbor’s property was sprayed, and my animals became sick as a result?
A: The pesticides that we use don’t have any effect on animals at all. (This response elicited some colorful language from the resident, followed by a heated discussion. They eventually agreed to disagree.)
Q: (Philippou) Have you had any complaints from abutters in any of the communities that you serve?
A: Absolutely not. We have a fairly good notification system in place.
A program driven by resident requests
Q: When do you spray?
A: The spray program 99 percent of the time operates on a resident-request basis. In the old days when Harvard was in the program, we sprayed quadrants of the town based on the calendar. We don’t do that anymore. When residents request spraying, we send out technicians to determine if they’re really having a problem with mosquitoes.
Q: (BOH member Sharon McCarthy) When a resident calls up to request spraying, they may be responding to a multitude of different mosquitoes. They don’t know what type of mosquito they have or if those mosquitoes are carrying any diseases. That seems like nuisance control.
A: We don’t know if mosquitoes are carrying viruses until they’re captured, identified, and tested. Or if they bite someone and the person becomes sick. We feel that, while the spray program can be a bit of a reactive-type program, the majority of the rest of our program is proactive. Also, reducing these species before they become infected with a virus can also be considered a proactive program.
A question of efficacy
Q: (McCarthy) What is the efficacy of spraying?
A: It varies, there are a lot of factors…
Q: (McCarthy) Just tell me, because the town’s going to pay a lot of money for some people who don’t want mosquitoes in their backyards.
A: The testing we’ve done shows that in three to five days, we start to see fly-in from untreated areas. In about five to six days, we see populations back to where they were.
Q: (McCarthy) Harvard has roughly 800 acres of Oxbow. U.S. Fish & Wildlife does not allow any treatment. There are acres and acres of conservation land that you don’t have access to with a truck, and there are many properties with a back forty that you don’t have access to.
A: We have been working with U.S. Fish & Wildlife to try to get them to alter their mosquito control policy, but to this date they have not.
Not convinced town is right for spraying
Q: (McCarthy) I have the results of a study on the efficacy of spraying in Massachusetts. They tested Framingham, Tewksbury, and Burlington, all much more suburban than Harvard. The result of that testing revealed no significant difference in the number of mosquitoes where they had sprayed and where they hadn’t sprayed.
They hypothesized that because of the distance between roads in rural areas, they couldn’t get to many areas. They also hypothesized that the shrubs that are so common in wooded areas prevented the spray from really distributing.
My concern is that spraying is not providing the protection that people think it’s providing because the spray is not getting past the woods in the front yard. I’m not convinced that the town of Harvard is an optimum place for spraying.
A: There are 51 species of mosquitoes in Massachusetts, and there are about 15 or so that we’re concerned with. They were only looking at two out of the 15. The mosquitoes they sprayed for live much higher in the canopy and come out later at night, so the spraying techniques do not work well on those mosquitoes. I don’t think that study relates all that well to the efficacy of our program.
Q: Isn’t the chemical you use derived from chrysanthemums?
A: Yes, we use pyrethroids, which are synthetic versions of pyrethrum. Pyrethrum is a naturally occurring insecticide found in chrysanthemums. What scientists have been able to do is make pyrethroids significantly safer.
Impact on mosquito predators
Q: Isn’t the spraying also killing the mosquito’s natural predators, like dragonflies?
A: There’s never been any data that I’ve been shown that shows there’s a significant impact on predators of mosquitoes. Dragonflies really are not a significant predator of the mosquito.
Q: Have there been studies done to show the impact of the pesticides you use on humans?
A: Yes, they can be found online.
Q: If we keep using the sprays, aren’t we going to get to the point where they don’t work anymore, and then we’re going to be into the next level of pesticides?
A: That’s called pesticide resistance. Our biologist tests for pesticide resistance every year, and we haven’t seen any resistance building up in the mosquito population.
The risk of disease in Harvard
Q: According to the Massachusetts Dept. of Public Health literature, Worcester County is a very low-risk area for West Nile mosquito virus and EEE. There have not been a lot of human cases.
A: Southeastern Mass. is the historic range for the virus, but it has been moving out of that area. Last year Tyngsborough had a horse death from EEE. We had it in Westborough two years ago.
Q: For mosquitoes that carry West Nile, where do they tend to breed?
A: They prefer containers.
Q: How about EEE?
A: The mosquitoes that carry EEE and bite humans tend to breed in cattails and in re-flood areas—areas that dry out and become wet again.
Q: What is their flight range?
A: Mosquitoes that breed in containers and carry West Nile tend to stay within about 100 yards of the containers. The EEE carrying mosquitoes that breed in cattails are strong fliers. They’ll fly upwards of a few miles.
What about nonchemical measures?
Q: (to board) I’m wondering about teaching people the importance of going into their yards and dumping out containers to prevent West Nile. And to prevent EEE, to stay indoors during the dawn and dusk hours.
A: (BOH member Lorin Johnson) We have coordinated with schools when they’ve had sports going on to get the kids off the field before sunset. We also put notices on the website.
Q: If there was a large outbreak of vector-borne illnesses, would the next step be massive spray?
A: Correct. A few years ago we had an EEE death of a horse in Lancaster. That next week we found EEE mosquitoes in Bolton. We coordinated with Bolton and did a town-wide application there, along with Lancaster and Clinton. I did reach out to Harvard. The testing in Harvard did not show anything at that time, and they felt that the situation was under control. But if public health had continued to find EEE in mammal-biting mosquitoes, then you would have had aircraft spraying regardless of where you lived.
Reducing number of mosquitoes reduces risk
Q: Where has it been proven that actual roadside spraying or sporadic larvicide applications are effective in controlling or preventing EEE or West Nile in humans? You mentioned that some cases have occurred in towns that had a program in place. Is there any evidence that roadside spraying actually helps prevent infection?
A: Reducing the number of mosquitoes will reduce the risk of humans contracting these diseases. The message we are always going to promote, to any resident in any community, whether we’re spraying or not, is that if a virus is found in your town, risk will not be zero until a hard frost. We recognize that we’re not a panacea. I’m not going to say that if you join mosquito control, you’ll never have a mosquito virus.
Q: If, instead of spending money on your services, we took that money and subsidized the buying of mosquito magnets, which don’t have chemical dispersion, and if we had enough people adopting the use of those machines, might that be more effective than anything you could do?
A: The issue we have with mosquito magnets is maintenance. You have to keep the propane filled. There are screens, filters, bags that have to be maintained, changed, etc. And you’re only looking at one little piece of the pie. There’s no larval control, no ditch maintenance, no tire recycling, no virus testing.
Q: (Philippou) Would it be possible for the town to become part of the CMMCP and not have any spraying done if that’s what the residents wish, and still partake of some of the other services that you offer a la carte?
A: No. Our Board of Commission does feel that the whole program should be offered to the residents and allow them to choose the level of service that they seek.
Q: (to board) Have we done any kind of independent testing to identify the types of mosquitoes that are inhabiting Harvard? As the agent here said, not all mosquitoes are vector-borne illness carriers.
A: (McCarthy) No, we haven’t tested.
Testing as a first step
Q: (to board) Wouldn’t it be a good first step if the BOH did an independent assessment of what types of mosquitoes we have?
A: (Johnson) This is exactly what this meeting is for. We want suggestions from people.
A: (McCarthy) I’ve identified two independent agencies that do contract testing.
A: (Philippou) I spoke with a resident over the weekend who had a wonderful suggestion about potentially contracting with a professor at one of the universities doing the same sort of thing as part of a project.
Q: (to board) Would you be willing to withdraw this warrant article as it is right now and to write a new one to have our town vote on hiring a truly independent agency to assess what sort of mosquitoes we have in our town?
A: (Philippou) Oh sure, absolutely. I’ve said from day one when we first posted the request to do the warrant article, really initially as a placeholder, that in all likelihood we’ll probably be withdrawing this at Town Meeting. But we wanted to start the conversation.
‘We can resolve this’
Q: Can you withdraw it right now and rewrite it?
A: (BOH Clerk Paige O’Brien) There’s no time now to put something else in. The deadline for monetary warrants has come and gone. This is an opportunity to start the dialogue at Town Meeting.
A: (Philippou) We have a lot of really intelligent people in this town, and if we get enough people to start thinking of solutions and working together collaboratively, we can resolve this for the town of Harvard. That’s really what we’re looking for. And that was what we were looking for when we decided to post the warrant article.
CMMCP is one of nine regional mosquito control programs in the state. These programs are overseen by the State Reclamation and Mosquito Board, which is housed within the Department of Agricultural Resources. CMMCP, headquartered in Northborough, serves communities in Worcester and Middlesex counties. For more information on the CMMCP, see their website at http://www.cmmcp.org.
