EVERYTHING GREEN: Practise ‘container management’
THE ADVICE might seem trite; it has been repeated often enough.
But for the Vector Control Unit, it is a bit of advice they want hammered home in the war on mosquitoes and the fight against dengue.
“Container management,” is how senior environmental health officer Maurice Gaskin puts it.
Mosquitoes are enterprising creatures whose eggs can remain viable for up to three years, just waiting for a drop of water in which to hatch.
A PET bottle cap can be the home of three or more larvae. And a female mosquito can lay up to 500 eggs in its three-week life span.
It is that kind of prolific breeding that has prompted Gaskin to reinforce his message of “container management”.
“My advice to householders is to look at container management. You need to remove containers, unwanted containers, from around the home,” he stressed.
“I would advise householders to spend at least twice per week inspecting around their premises. I don’t mean the yard only, I mean inside the house, as you can see what can happen with the plant,” he said.
He was referring to how a mosquito can lay eggs not only in the water left in the plant’s saucer, but on the outside of the pot, below the rim of the water line. When the water recedes, the eggs remain until a homeowner wets the plant and the water level in the saucer rises again.
Those eggs then hatch into mosquito larvae and the cycle continues. He suggests using ice, which would melt slowly, instead of watering the plant.
Gaskin also advises homeowners to widen their inspection to areas outside the gates as they check for stagnant water.
But Gaskin was not engaging in a “do-as-I-say-but-not-as-I-do” scenario.
He and his colleagues at the Ministry of Health’s Vector Control Unit have been waging war on the small pest on all fronts.
Wetlands are visited, ponds are inspected, and “traps” are set at the air and sea ports. It’s all in an effort to ensure the population of mosquitoes remains at low levels.
There are three types of mosquitoes in Barbados, said Gaskin: the Anopheles, the Aedes Aegypti and Culex.
“We go around to wetlands and ponds and we do testing for the Anopheles. Despite the fact that Anopheles is no longer found at Three Houses (St Philip) and Holetown (St James), we still do wetland management and we do testing,” Gaskin explained.
In addition, “traps” are set at the Grantley Adams International Airport, the Bridgetown Port and Port St Charles.
It’s called ovi trapping, and Gaskin explained the concept at a recent recycling fair at the Lloyd Erskine Sandiford Centre. Forty “traps” are at the airport, more than 40 are at the sea port and some are at Port St Charles.
“What we have is a container painted black and a piece of cardboard. We half fill it with water and we place these behind counters at the airport,” he said.
“So say that the mosquito goes through a complete metamorphosis from egg to adult in seven to 13 days, every seven days we go to the airport, we remove a wet ‘stick’ and replace it with a dry one.
“These are taken to the Vector Control Unit and we allow them to dry and we look at the palette under a microscope,” Gaskin said.
If there are six or seven positive palettes, inspectors from the Randall Phillips Polyclinic are pressed into action in the hunt for mosquito breeding grounds in the vicinity.
The airport would also be fogged room by room.
But Gaskin hastens to add that the results so far have been good. What ovi trapping also did, said the senior environmental health officer, was to allow health officers to see if other species of mosquitoes had invaded the island.
Homeowners, he said, should also try their hands at it. But failing that, he suggests that should mosquito larvae be found, bleach, kerosene oil or diesel were the best methods for killing them.