Further efforts are needed to keep the mosquito responsible for dengue fever under control in Bermuda.

Environmental Health Officer David Kendall spoke at the Hamilton Rotary Club yesterday at the Chamber of Commerce Building on the threat of disease carrying mosquitos in Bermuda.

Mr. Kendall confirmed that the dengue fever mosquito, Aedes aegypti, has been on the Island since 1998 though it was thought to have been eradicated in the 1960s.

The fever causes internal bleeding which can be life threatening. Mr. Kendall cited the devastation caused by the virus in Indonesia. Over 800 people have died, and 80,000 people have suffered from dengue fever from between January and March of this year alone.

The mosquito species can be identified by its black and white stripes and the tendency to bite around the ankles and feet in the evening hours. Unlike the common mosquito, the dengue fever mosquito does not make a whining noise.

Upon confirming the mosquitos' presence in Bermuda, the Department of Health Mosquito Vector Control Team has increased its Islandwide coverage, including a campaign for mosquito control called "Fight the Bite". The team performs house-to-house inspections and community education among other criteria that comply with anti-mosquito breeding laws.

Mr. Kendall stressed that Bermudians "must not wait until (they) are being bitten", but instead Bermudians have a "collective responsibility" to act now and eliminate standing water on their neighbourhoods.

Female mosquitos lay 100 to 150 eggs in standing water, which cannot be seen by the naked eye. What is unusual about this species of mosquito is that the eggs are covered by waxy shells which protect them from drying out. Mr. Kendall said that the mother mosquito glues the eggs to a vertical surface such as the sides of a bucket. As a result, even when such containers are emptied, the eggs can may "lay dormant for a year or more until conditions are right to hatch out".

Mr. Kendall said that the only way to ensure that larvae in a container of water are destroyed is to scrub the insides of the containers. Otherwise, when the container is filled again, the larvae will hatch, and the cycle will continue.

Mr. Kendall speculated that the mosquitos have come to Bermuda in containers that contain standing water from other countries. Originally, the mosquito was transported out of Africa in the water barrels carried on slave trade ships.

Mr. Kendall said that Bermudians do a good job of clearing standing water from their own properties but that we must now look to clear man-made water containers from such land on the railway trail, the tribe roads, and undeveloped land.

Mr. Kendall said that US bases in Bermuda were largely responsible for the eradication of the mosquito after Bermuda's last outbreak in the 1940s.

Mr. Kendall clarified that this disease is different from the West Nile virus that plagues the US. The West Nile virus spreads through bird populations, whereas this virus spreads through the mosquitos themselves.

Viruses are usually destroyed in a mosquito's stomach, but dengue fever is able to survive and is then transmitted when a mosquito bites a human and injects contaminated saliva.

Mr. Kendall said that guppies eat mosquito larvae and should be used in fish ponds to help keep the vector mosquito population down.