Mosquito surveillance programme underway

From disease transmission to nasty bites, some insects just aren't nice neighbours

Female malaria mosquito (Anopheles funestus) biting a human arm

For starters, let’s declare an interest. I’ve a grudge against mosquitoes. The little devils seem to go for me mercilessly whenever I visit sunny climes. I never see them doing it, though I certainly feel the irritation when lumps start rising on my skin. So, on a personal note, they’re not welcome here.

The above rant arises from the recent discovery of an Asian hornet, a notorious wasp, in Cork — a clear sign of what we can expect in the way of invasive species arriving on our shores as the climate progressively warms.

Vespa velutina nigrithorax, the Asian hornet, originates from Southeast Asia and is an invader wasp that has appeared in Europe in France, Spain and Portugal. Although the species is not aggressive there have been reports of people hospitalised after suffering anaphylatic shock. The wasp hunts insects and causes very important losses in apiaries by killing a significant amount of honey bees

Mosquitoes — already confirmed to be in Ireland, even if in small numbers — are an example.

Mosquitoes can transmit a number of diseases to people. An ongoing surveillance programme to check for invasive mosquito species here is being carried out by the HSE’s National Environmental Health Service.

Such species include the Asian tiger mosquito which is associated with the spread of diseases like malaria, yellow fever, and other viruses.

Replying to a query, the HSE tells us the service has never detected an invasive mosquito species here. The only two species found were considered common native mosquitoes, in 2023/’24. Out of 72 inspections across five areas of Dublin Port, in 2023, just three samples had mosquitoes present.

A monitoring programme runs from April to October at Dublin Port and Airport, New Ross Port, Waterford Port, Cork Port, Limerick Port, Shannon Airport, Fenit Port, Knock Airport, Sligo Port, and Carlow/Kilkenny.

Studies by the European Centre for Disease Prevention and Control (ECDC) show mosquito species are slowly starting to migrate further north, possibly due to climate change and increasing global traffic.

The likelihood is that they come on ships, trucks or other vehicles rather than making the long journey on their own steam. While confirming their presence in Ireland, a HSE spokesperson said their numbers are very low because of our current climate.

An old tire holding some stagnant water which makes an excellent breeding ground for mosquitoes

The spokesperson continued: “However, as all models of climate change are predicting a rise in temperatures, this can create a climate that is more suitable for the spread of mosquitoes and the potential for the spread of viruses that come with those mosquitoes.

“The HSE national environmental health service will continue to build on the progress made, in 2023, and are looking at extending our surveillance programme for 2024/’25."

One thing about mosquitoes is that they are highly adaptable and have spread to almost every country. Widely seen as a pest, they are also a food source for birds, fish and bats. They like warm, humid conditions and can be found around stagnant water, wetlands. and woodlands.