Heat and Your Health Public Health – Factsheet

How does heat affect my health? – If you have an air-conditioner, make sure it’s working properly before the hot weather starts. Your body is always trying to keep a consistent temperature (about 37ºC or 98.6ºF) but becomes • Stay hydrated overworked if you are exposed to heat for too long. – Drink plenty of water (that’s the best liquid) This can lead to dehydration, heat exhaustion, heat before you feel thirsty. stroke (sun stroke), other serious illnesses or even death. Fortunately, most heat-related illnesses can – Avoid alcoholic beverages, as they can increase be prevented or treated if you are aware of the risks the amount of water lost by the body. and symptoms and take action to protect yourself • Stay cool and keep out of the sun and others. – Plan outdoor activities for cooler parts of the day, but remember to wear insect repellant since Who is at risk from heat? mosquitoes are out, too. When it’s hot out, everyone is at risk for heat related – If you are outdoors during the hottest part of the illnesses. However, the health risks are greatest for: day, shade yourself from the sun with an • older adults umbrella or a wide-brimmed hat with lots of • infants and young children ventilation (to allow the sweat on your head to evaporate), wear loose-fitting, breathable, • people with chronic conditions, such as breathing light coloured clothing, and remember to wear difficulties or heart problems sunscreen to limit ultra-violet (UV) ray exposure. • people who work or exercise in the heat (even if – If there is no air-conditioning at home- go to a they are healthy), or cool place such as an air-conditioned mall, public • other vulnerable people, like people experiencing library, or community centre. homelessness, mobility issues, or confusion/altered – Take a cool bath or shower or go for a swim to mental status cool off. Anyone can put themselves at risk by over-exercising – Avoid using your oven or other appliances that in hot weather because the body has to work even could heat your home more. harder to stay cool. – Limit physical activities during the hotter parts of Certain drugs such as amphetamines, MDMA (ecstasy), the day or exercise in an air-conditioned place. cocaine, alcohol, and cannabis can alter mental status as well as increase the risk of hyperthermia. Some • Take care of yourself and others medications can also increase your risk, so it’s – Check on family members, neighbours and important to ask your doctor or pharmacist whether friends—especially older adults and those with the medication you’re taking affects your ability to chronic conditions. Visiting is best because it is cope with heat. easier to identify signs of heat illness that could What can I do to protect myself and be missed over the phone. others? – Never leave people or pets in your care alone in closed vehicles or direct sunlight. All heat illnesses can be prevented by following these simple steps: • When do heat-related illnesses usually happen? • Stay aware and be prepared – Some people are more sensitive to the effects of heat than others. However for most people, – Know daytime and nighttime temperatures— heat-related illnesses happen when temperatures both outdoors and indoors—by checking your are higher for a number of days, particularly if local weather forecasts and the thermostat in the nighttime temperatures do not drop or if your home. humidity is high. – Stay up to date on weather alerts so you know when to take extra care.

July 2021 Heat and Your Health

How does heat affect my body? • confusion Exposure to heat can lead to a variety of symptoms • nausea ranging from mild to more severe and may include: • rapid, strong pulse • headache • a complete or partial loss of consciousness • nausea While waiting for help to arrive, immediately move the • dizziness person to a cool place, sponge large areas of the skin with cold water and fan the person as much as possible. • weakness or tiredness The longer a person’s body temperature is above 40ºC • fainting (105ºF), the greater the likelihood of permanent effects • confusion or death. • swelling of the ankles, feet or hands How hot is too hot? • muscle cramps Extreme heat events or “heat waves” occur when • rapid breathing or rapid pulse weather conditions combine to create higher than normal temperature and humidity levels over a period • dehydration, and of several days. This increases the potential for • elevated body temperature heat-related illnesses. What are the symptoms of heat exhaustion? There is no universal definition of what is considered a “heat wave” or “too hot”, because these terms depend Heat exhaustion occurs when the body loses too much on what is considered normal for a specific location water and salt. Symptoms can include: and person. • headache Temperatures that people from a hotter climate consider • nausea normal may be considered a heat wave in a cooler area if • muscle cramps they are above what is normal for that area. • pale and clammy skin What is considered “too hot” can also vary from person to person depending on a variety of factors, such as age, • dizziness or fainting chronic conditions, level of activity, and the level of • rapid breathing and/or heartbeat acclimatization (what temperature the individual is used If you or someone you know experiences any of these to for the given activity level), on a hot day. symptoms, move to a cool or shaded place immediately, Where can I get more information about drink sips of water, lie down and sponge yourself with cool water, if possible. heat and health? Manitoba government: What is heat stroke? www.manitoba.ca/health/publichealth Heat stroke (sun stroke) is the most serious type of environmentalhealth/heat.html heat illness and requires urgent medical attention. If someone you know experiences signs of heat stroke, Health Canada: dial 911 immediately. https://www.canada.ca/en/health-canada/services/ During heat stroke a person will have a core body sun-safety/extreme-heat-heat-waves.html temperature that is above 40ºC (105ºF). Symptoms of Call Health Links—Info Santé at 204-788-8200 or heat stroke may include: toll free 1-888-315-9257 • headache • red, hot, and dry skin • dizziness

MG-16032 Rev. 07/21