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If it feels like mosquitoes are everywhere this summer, you're not imagining it.

An unusually wet spring followed by warm temperatures has created ideal breeding conditions across Calgary, leading to an early and persistent mosquito season. While this is not the worst year on record, researchers say the insects emerged sooner than usual and have remained active throughout the summer.

The season has also brought an important milestone. Calgary's first West Nile-positive mosquito sample was collected at the end of June, making it the earliest detection since monitoring for West Nile in mosquitoes restarted a few years ago. Since then, additional positive collections have been found, as well.

, PhD, associate professor at the Ä¢¹½ÊÓƵ , works with The City of Calgary to monitor mosquito populations throughout the summer. Using traps placed across the city, researchers identify mosquito species and test them for West Nile virus, helping track when and where the virus is circulating. This work is a collaborative project being conducted through the , a strategic research partnership between the Ä¢¹½ÊÓƵ and The City.

"Finding West Nile virus in mosquito samples is like finding a needle in a haystack," says Soghigian. "The fact that we found it this early tells us the virus is already circulating in Calgary."

An invasive mosquito is becoming more common

The positive sample came from the northern house mosquito (Culex pipiens), an invasive species first detected in Calgary in 2022 after becoming established in Edmonton several years earlier.

Soghigian and his team have been tracking the species as it becomes more abundant in southern Alberta. Unlike many native mosquito species, Culex pipiens is particularly effective at transmitting West Nile virus.

"We've seen this species increase in abundance over the last few years," says Soghigian. "It's different from our native mosquitoes, and understanding where it's spreading helps us better understand the risk of West Nile virus."

Researchers have identified four mosquito species carrying West Nile virus in Alberta over the past three years, and Soghigian expects that list could grow as monitoring efforts continue.

Why there are so many mosquitoes this year?

This summer's weather has created what Soghigian describes as a perfect storm for mosquito development.

Frequent rainfall has created abundant standing water across the city, while warm temperatures have accelerated mosquito growth. Mosquitoes can complete their development from egg to adult in as little as a week, meaning even temporary pools of water can become productive breeding sites.

"We started seeing mosquitoes earlier this year and they've continued throughout the season," says Soghigian. "The rain created ideal breeding conditions, and the warm temperatures allowed populations to build quickly."

Researchers expect mosquito activity to remain elevated for much of the summer.

"Unfortunately, there's no silver bullet for mosquitoes," says Soghigian. "There are simply too many of them and too many different species."

Small steps can reduce risk

The mosquitoes most commonly associated with West Nile virus are most active around dawn and dusk. During those periods, Soghigian recommends taking simple precautions to avoid bites.

Wearing long sleeves and loose-fitting clothing can help reduce exposed skin, while insect repellents remain one of the most effective tools for protection. Products containing DEET or oil of lemon eucalyptus have both been shown to work well, although DEET can damage certain synthetic materials. People spending extended periods outdoors may also consider permethrin-treated clothing, which is highly effective at repelling mosquitoes.

Soghigian notes that repellents need to be reapplied regularly, especially after sweating, because their effectiveness decreases over time.

Homeowners can also help reduce mosquito populations around their properties by eliminating standing water wherever possible. Uncovered rain barrels, bird baths, pet bowls, flowerpot saucers and children's toys can all become mosquito nurseries if water remains stagnant for several days.

"If water sits for about a week, that's enough time for mosquitoes to develop," says Soghigian.

Understanding the risk

Most people infected with West Nile virus never develop symptoms. Others may experience a mild illness that resembles the flu and resolves on its own.

In rare cases, however, the virus can cause serious neurological disease, including inflammation of the brain. Those severe outcomes are more likely to occur in older adults, people with weakened immune systems and young children.

Soghigian emphasizes that people should not be alarmed if they are bitten by a mosquito.

"The virus is out there, but that doesn't mean people need to panic," he says. "Most mosquitoes are unlikely to be carrying West Nile virus. The important thing is to be aware, take precautions to avoid bites and seek medical attention if you develop severe symptoms such as a serious headache or neurological problems."

As Calgary moves through the remainder of mosquito season, researchers will continue monitoring mosquito populations and testing samples from across the city. For Soghigian, the message is straightforward: awareness and prevention remain the most effective tools available.

"People don't need to stop enjoying summer," he says. "They just need to remember that mosquitoes are active, West Nile virus is circulating, and a little prevention can go a long way."