Everything you need to know about mosquitoes in the NWT

It’s that time of year in the Northwest Territories when the days are long, the weather is warm, and pesky mosquitoes are biting every morsel of skin they can find.

Entomologist Taz Stuart told Cabin Radio that northerners will notice more mosquitoes this summer than in recent years due to increased moisture and more water bodies.

The past four years of hot weather and troubling drought had temporarily reduced numbers of the water-loving insects in the NWT, but some water levels across the territory are showing signs of recovery this year.

More than 80 species of mosquito are known to exist in Canada, nearly 40 of which can be found in the NWT – including the Woodland Pool Mosquito, Confusing Mosquito and Impatient Winter Mosquito.

Stuart said his company discovered nine species that were new to the territory between 2011 and 2018. He said that shows climate change is “making conditions conducive for more species.”

“We’re seeing the expansion of different mosquito species throughout Canada,” he said.

Beyond Canada, mosquitoes were found in Iceland for the first time last year due to rising temperatures in the Arctic. Before then, Iceland was one of the only countries in the region without mosquitoes.

Humans aren’t the only ones affected by changes in mosquito behaviour.

Mosquito “harassment” has been shown to affect caribou in the Arctic. Warmer summers that arrive earlier mean the insects pose more of a nuisance to caribou, who will move to cooler, windier areas to get away from the bugs. That means caribou spend less time eating high-quality food, which can reduce reproduction rates.

To completely get away from the whining insects, you’ll have to move to the other end of the globe. Antarctica is the only continent on Earth that is mosquito-free due to its extreme cold and dry conditions.

Mosquito bite facts

While mosquitoes are known for biting humans and animals, only female mosquitoes bite as they need the proteins and iron found in blood to produce eggs. Male mosquitoes feed solely on the nectar from plants.

Research has found some people are genetically predisposed to being mosquito magnets while the insects are attracted to carbon dioxide, natural skin odours, body heat, and dark clothing.

Studies suggest people with higher levels of compounds called carboxylic acids on their skin are more attractive to mosquitoes, alongside pregnant people and people who recently drank beer or consumed cannabis.

Mosquito bites become itchy and swollen` because the insects’ saliva – which it injects into your skin when feeding – triggers your immune system to release histamine.

While it can be hard to resist, experts say you shouldn’t scratch mosquito bites as doing so can worsen inflammation and cause the release of more histamine, leading to a frustrating itch-scratch cycle. Scratching can also damage your skin and possibly lead to infection.

Recommended itch relief remedies include ice and elevation, oral anti-histamines, anti-itch lotions, and over-the-counter corticosteroid creams.

Most people have some kind of a reaction to mosquito bites, though some are more sensitive than others.

Some individuals can experience what is known as “skeeter syndrome,” an immune system overreaction to mosquito bites resulting in severe swelling, redness, warmth, itchiness, pain and sometimes blistering.

In some cases, people may get a fever, hives or swollen lymph nodes and, in very rare cases, people have reported experiencing anaphylaxis, a potentially life-threatening allergic reaction.

Skeeter syndrome is most common in infants and young children, immunocompromised people, and immigrants or visitors to a new region.

The best medicine is prevention

Beyond making you itchy and irritable, some species of mosquito can also transmit diseases such as the West Nile virus, Jamestown Canyon virus, snowshoe hare virus, eastern equine encephalitis, and St Louis encephalitis.

The risk of contracting a mosquito-borne virus in the NWT is very low. Most mosquitoes found in the territory do not carry diseases that can be passed on to humans.

Culex tarsalis or the Western Encephalitis Mosquito, a species known for carrying and transmitting the West Nile virus, has been found in the NWT. However, testing has not detected malaria, the West Nile virus or Zika virus in the territory.

According to the GNWT, in rare cases mosquitoes in the territory can carry California serogroup viruses, which include the Snowshoe Hare and Jamestown Canyon viruses.

There are plenty of products on the market to prevent mosquito bites, along with tips and DIY options shared online or by word of mouth – some of debatable effectiveness.

Stuart said his favourite mosquito repellent to use is Off! Deep Woods, made with 30 percent Deet, which stands for the chemical N,N-diethyl-m-toluamide, the gold-standard active ingredient in insect repellent products. For people who are allergic to Deet, he suggested Off! Gentle.

“People need to realize that personal protection measures are key,” he said.

“Never assume. There could always be that one species that could be a potential vector being brought in on shipping materials, trucks, cars.”

To Deet or not to Deet

Recent research found Deet-based based products consistently provided the longest complete protection from mosquitoes, often lasting five to nine hours.

The study found natural repellents based on essential oils provided complete protection for two to four hours, while wearable products such as insecticide treated clothing and spatial repellents were best thought of as complementary measures in high-transmission settings.

Health Canada has said insect repellents containing Deet can be used safely when applied as directed in the right concentrations depending on age.

According to a study published in the Journal of Experimental Biology in May, researchers were able to train some mosquitoes in a lab to associate Deet with the presence of a “blood meal,” and even become attracted to it, much like Ivan Pavlov trained dogs in the 1890s to associate the sound of a ringing bell with food.

But researchers said that does not mean people should ditch Deet-containing insect repellents. Instead, they said, the results indicate that low concentrations of Deet that fade over time may be too weak to repel mosquitoes but strong enough to signal food, meaning people should reapply regularly.

Previous research has suggested some mosquitoes may have a genetic insensitivity to Deet, while others may become less sensitive to Deet following exposure.

“Any product you use, there’s always going to be that outlier,” Stuart said.

While mosquitoes may present as a problematic, blood sucking pest, they are important to the ecosystem.

Mosquitoes serve as an important food source for animals like fish and birds as well as other insects such as dragonflies. They also act as pollinators for plant species and help connect aquatic and terrestrial ecosystems.