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This 2006 photo made available by the Centers for Disease Control and Prevention shows a female Aedes aegypti mosquito acquiring a blood meal from a human host at the Centers for Disease Control in Atlanta.Centers for Disease Control and/The Canadian Press

For many sun-starved Canadians, summer is a favourite time of the year.

Days are long, windows are open, water is inviting and the world is green and blue. Down-filled jackets and scratchy woollen wear get shoved to the back of the closet – for a few months, at any rate.

As glorious as it is, summer poses a few health perils. Here are some things you'll want to avoid and what to do about them if the season throws them in your path:

West Nile virus

Certain species of mosquitoes pick up this virus from infected birds and pass it on to humans. Depending on where you live in Canada, those species are Culex tarsalis, Culex restuans and Culex pipiens.

Most years, human cases of West Nile start to be diagnosed in late July and infections can continue to occur until frosts kill mosquitoes in the fall.

Some years there isn't much West Nile activity. Last year, there were only 21 cases reported in Canada. But in 2007 – the worst year on record – there were 2,215.

What's critical here is how much hot weather there is early in the summer, when virus levels start to build up in birds and bugs.

"It's too early to tell how intense the West Nile season will be. It will depend on basically temperatures that we get from now on in, the numbers of … Culex tarsalis mosquitoes we get and virus levels in birds," says Phil Curry, an entomologist with Saskatchewan's Ministry of Health.

The illness can be mild and almost flu-like. But some people develop encephalitis or meningitis – swelling of the brain or the membranes surrounding the brain – and some people die.

The best way to avoid West Nile is to avoid being bitten. That means wearing long sleeves and trousers, dressing in light colours and using DEET-based insect repellents to protect against the dusk-till-dawn biting mosquitoes that carry the virus.

It also means getting rid of standing water on your property because mosquitoes need water to breed.

Poison ivy, poison oak and poison sumac

You don't want to run into – or brush up against – these rash-inducing forms of flora.

But you need to know what you should be avoiding to successfully do so. A little time on the Internet ought to help you identify foliage to avoid.

According to the federal government's website, Newfoundland is the only Canadian province where poison ivy is not found. On the other hand, poison oak is found only in southern British Columbia.

Words of warning: Poison ivy is pesky. If you get the sap on clothing, it can trigger rashes long afterward if it isn't washed off.

And if you are trying to rid a property of poison ivy, don't burn the plants. That can release the urushiol – the component that causes rashes – into the air. Breathing in that smoke can trigger severe and even potentially fatal breathing problems.

If your skin comes in contact with any of these plants, wash the exposed skin with soap and cold water. If there is no soap at hand, vinegar and water (30 millilitres/two tablespoons in 250 millilitres/one cup of water) or alcohol and water (half and half) can help.


We're talking blacklegged ticks here, the kind that can transmit Borrelia burgdorferi. That's the bacterium that causes Lyme disease.

It wasn't that long ago that infected ticks were found only in a few spots in the southernmost part of Canada, near Windsor, Ont. But the Public Health Agency of Canada says blacklegged ticks can now be found in a number of provinces. It has posted a map detailing high-risk areas .

Ticks latch on to people (or animals) and take a blood meal. The bacteria only transfers when the tick has been feeding for quite awhile, around 36 to 48 hours.

Ticks – especially the juvenile ones – can be hard to spot. But doing a tick check after being outdoors as well as taking a shower and laundering your clothing should help you avoid being the source of a prolonged meal.

Dr. Doug Sider of Public Health Ontario says these ticks like areas with brush and high grasses.

"You're not going to get Lyme disease risks in manicured lawns and sports fields. … That's not where the tick hangs out."

If you find a tick a few hours after walking in the woods, Sider says the advice would be to remove it carefully – pull it straight out with tweezers – and not to worry about it.

If, however, you find a tick a couple of days after your last trek through the woods, the second part of the recommendation might change.

If you are living in an area known to have infected ticks, your doctor or hospital may give you a dose of an antibiotic that kills the bacterium, says Sider, the agency's medical director for communicable disease prevention and control.


Hornets, wasps, bees: They play a vital role in nature, but they sure can take the fun out of a summer picnic or meal on a patio.

For most people the pain of an insect sting is short-lived. If you are one of these people, remove the stinger, apply a cool compress or use something such as hydrocortisone, lidocaine or calamine lotion, the Mayo Clinic's website suggests.

However, some people are allergic to insect stings and can have severe, even fatal, reactions if they are stung.

If you are with a person who develops trouble breathing, dizziness, confusion, rapid heartbeat, nausea or vomiting after an insect sting, this is a situation to take seriously. suggests seeing a doctor right away. Ask if the person is carrying an epinephrine autoinjector – an EpiPen – and if yes, whether he or she needs help to use it. If the person stops breathing, begin cardio-pulmonary resuscitation (CPR).

Stinging and blood-sucking water creatures

We're talking about jellyfish and leeches here. The former are found in salt water and the latter in fresh.

Jellyfish stings can vary in severity, according to information on them posted on the Mayo Clinic's website.

Most just cause pain and redness, though some will trigger a whole-body response, including nausea and difficulty breathing. If you have the latter type of response, you need to seek medical help.

For regular jellyfish stings, the Mayo site suggests making sure none of the stingers are left on your skin by rinsing the area with salt (not fresh) water. You can also rinse with vinegar and a paste made of baking soda and salt water.

As for leeches or bloodsuckers, don't try to pull them off. Pouring salt or vinegar on them will make them release their grasp on your skin and drop off.


Summer sun feels great on the skin. But too much exposure to the sun's ultraviolet rays can prematurely age and permanently damage skin. It can also lead to melanoma, a dangerous form of skin cancer.

Do your future self a favour: Avoid excessive tanning and sunburns. Limit the amount of time you spend in the sun when its power is at its peak, between 10 a.m. and 4 p.m.

Use sunscreen. The Canadian Dermatology Association recommends choosing a product with a sun protection factor (SPF) of 30 or higher. It should be reapplied every two hours or after swimming or sweating a lot.

Wear a hat. Protect your eyes from the sun, too – UV light may contribute to the development of cataracts.

Be especially vigilant protecting children from the sun.

And if you do get a burn? Soothe sunburned skin with a cool compress; a moisturizer, gel or lotion containing aloe vera; or hydrocortisone cream.