For the first time
since the early 1990s, pesticides have been sprayed to combat mosquitoes in
Rhode Island. An independent pest company applied the insecticide sumithrin on
the night of Aug. 23 to marsh areas in the Common Fence Point and Island Park
neighborhoods in Portsmouth.
This needed
extermination may or not be another sign of climate change, but warmer weather
is to blame, according to Alan Gettman, mosquito abatement coordinator for the
state Department of Environmental Management (DEM). “It was such an unusually
warm winter that the (mosquito) population built quicker," he said.
Last December was the second warmest in Rhode Island since 1895. March was that state’s warmest ever, a full 7.7 degrees above the average, and the past decade has been the warmest on record. According to the Rhode Island Ocean Special Area Management Plan, winters are expected to be 5 to 7 degrees warmer by 2100.
Gettman said there is
no direct link between last winter and climate change, but mosquitoes and other
insects were predictably ubiquitous this year.
Fortunately, the
mosquitoes in Portsmouth were just a nuisance to residents, and not the species
carrying West Nile virus and Eastern Equine Encephalitis (EEE). Both diseases
can be fatal. EEE has a one-third mortality rate and survivors pose a high risk
of neurologic damage. West Nile virus is more common, but only about 20 percent
of people infected show symptoms, often a mild fever. Less than 1 percent of
cases are fatal.
This year, three
mosquito pools in Rhode Island have tested positive for EEE and West Nile
virus. Most recently, a positive report of EEE occurred Aug. 20 in north
Tiverton. The Highlands J virus, which only infects birds, was detected near
Wickford on Aug. 27.
Nearby southeastern
Massachusetts is a haven for West Nile virus and EEE. The region's prevalence
of hardwood freshwater swamps is ideal for infected mosquitoes, according to
Gettman. Last year, a Raynham, Mass., resident died from EEE. This year, the
illness is showing up in less common regions. A Worcester-area man died last
week from EEE, an infection was reported in western Massachusetts and two cases
were reported in Vermont, one fatal.
Gettman said both
diseases can likely be found across Rhode Island. There are currently no plans
for spraying to combat the diseases.
Cooler weather is the
best defense against infected mosquitoes. By mid–September, they begin dying
off and most are typically killed off with first hard frost in October. But not
all die off, a small number of eggs, larvae and even mosquitoes make it through
the winter.
“We can look forward
to decreased mosquito biting as the weather becomes cooler in the weeks ahead,”
Gettman said.
Until then, the DEM
recommends eliminating mosquito breeding grounds from yards by removing
standing water from old tires and buckets, to clean gutters so that they drain
correctly, and maintain swimming pools properly. Wear protective clothing at
dawn and dusk, and putting mosquito netting over playpens and baby carriages
when they are outside.
About sumithirn
Sumithrin (d-phenothrin) is a common pesticide against adult mosquitoes and other insects such as fleas, tics and bed bugs. It’s used for household, commercial and aerial spraying. According to the Environmental Protection Agency (EPA), sumithrin poses some chronic risks to mammals, and acute risks to honey bees and marine life. It is a suspected endocrine disruptor, a neurotoxin, and can cause kidney and liver damage.
Sumithrin (d-phenothrin) is a common pesticide against adult mosquitoes and other insects such as fleas, tics and bed bugs. It’s used for household, commercial and aerial spraying. According to the Environmental Protection Agency (EPA), sumithrin poses some chronic risks to mammals, and acute risks to honey bees and marine life. It is a suspected endocrine disruptor, a neurotoxin, and can cause kidney and liver damage.
