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Hay fever

You may have heard the term "hay fever," but seasonal allergies, also known as seasonal allergic rhinitis, are triggered by several different types of pollen, but not by hay. When trees and grasses begin growing in the spring and early summer, they release light, powdery pollen that floats in the wind. If you're allergic to this pollen, it can result in sniffling, sneezing, wheezing, a runny nose, and itchy and watery eyes. For some people with asthma, pollen can also trigger an asthma attack.

Allergy triggers, or allergens, vary depending on the time of year. In late summer and early fall, weed pollen (especially from ragweed) and fungal spores are the main culprits. In the early spring, tree pollen is the usual cause, and in late spring and summer it's grass pollen that's the problem. As well, the specific allergens in the environment will vary with the geographical area.

So if you're an allergy sufferer, how can you enjoy the outdoors without experiencing unpleasant symptoms? Here are a few tips:

  • Keep windows closed so pollen can't drift in. Air conditioning will keep you more comfortable in hot, humid weather. But don't forget that air conditioners also create the best conditions (damp and dark) for mould to grow in your home. Do some spring cleaning, and do it regularly.
  • If possible, stay inside when pollen counts are high (watch for these in weather reports) and on windy days when pollen and spores can get blown around. Avoid being outdoors in the early morning hours (between 5 am and 10 am), when pollen counts are usually highest.
  • If you've been outside all day, remove all your clothing and put it aside to be laundered, and take a shower after coming home. This will prevent you from taking all that pollen to bed with you.
  • Don't hang your laundry outside to dry – it can trap pollen and mould, bringing them inside. Use your dryer instead.

If these measures don't work, talk to your health care provider about what you can do if you're suffering from allergies. There are eye drops, nasal sprays, oral antihistamines and anti-allergy medications, sinus rinses, and even allergy shots that can be helpful in treating your specific allergy. Many treatments are available without a prescription, but others will need a prescription from your doctor. If you have asthma and have seasonal allergies, monitor your asthma closely and follow the action plan your doctor gives you.

All material copyright MediResource Inc. 1996 – 2023. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source:

It's in the water!

When you're camping, it's tempting to drink water straight from pristine-looking lakes and streams – but don't do it! Microscopic single-celled parasites can cause illnesses in humans if ingested. Here are 2 common waterborne diseases that could ruin your week:

  • Cryptosporidiosis (crip-toh-spore-id-ee-oh-sis) is caused by Cryptosporidium (crip-toh-spore-id-ee-um). The symptoms include diarrhea, headache, nausea, and stomach cramps. It usually shows up 1 to 12 days after becoming infected, and the symptoms usually last for 1 to 2 weeks.
  • Giardiasis (jee-ar-dye-a-sis), also known as "beaver fever," is caused by Giardia (jee-ar-dee-ah). It shares similar symptoms with cryptosporidiosis. Symptoms include diarrhea, gas, stomach cramps, weakness, and weight loss. Vomiting, chills, and headache may also occur. Symptoms first show up 7 to 10 days after becoming infected and can last for as long as 6 weeks.

How to prevent waterborne diseases:

  • Use bottled water only, or boil water at least 5 minutes before using it. Alternatively, you can purify water with iodine tablets or special water filters.
  • Use purified water to brush your teeth, wash dishes, fruits, or vegetables, and make ice cubes.
  • Peel raw fruits and vegetables before you eat them.
  • Wash your hands with bottled or purified water only, and do it carefully several times a day.
  • Don't swallow water when you're swimming – even in a chlorinated swimming pool (chlorine doesn't kill all germs).
  • One easy way to remember how to keep it safe: "Boil it, cook it, peel it, or leave it!"

If you think you have cryptosporidiosis or giardiasis, see your doctor right away. You may need to give stool samples to see if you have the parasite, and then get treated with prescription medications to get rid of it for good.

All material copyright MediResource Inc. 1996 – 2023. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source:

Poison ivy

Contact dermatitis is another kind of allergy, one that appears as a skin rash after you have touched some sort of allergen. One of the most common triggers of contact dermatitis in the great outdoors is poison ivy. The resin of the plant contains an oily substance called urushiol that's easily released and spread when the leaves are crushed, rubbed, or burned.

About 50% to 70% of people will react to poison ivy when they come into contact with it in nature. Within 12 to 48 hours of exposure to this innocent-looking shrub, susceptible people will typically develop an itchy rash, starting as reddened skin, leading to bumps and blisters. After a few days, the blisters break and the oozing sores begin to crust over and heal.

Your best defense is to avoid contact with poison ivy plants. Learn to recognize them by their slightly glossy green leaves growing in groups of three – but their shape can vary. If you're in heavily wooded areas and it's impossible to avoid them, wear long sleeves, long pants, and gloves. Remember, the oils can cling to your family pet's fur, so be careful when handling your pet after spending time in wooded areas – a bath may be necessary.

What if you're unlucky enough to get some urushiol on you? First, try to wash it off right away. Even a running stream will do, but soap and water is best to keep the oil – and the rash – from spreading. The rash will usually go away on its own in a few days, but it can be uncomfortable in the meantime. Wet cold compresses can soothe the rash, while calamine lotion can provide relief. Bathing in water prepared with colloidal oatmeal can also be soothing. Oral antihistamines can be helpful in controlling itchiness. See a doctor if the rash is severe, is on the face or genitals, covers a large area of the body, is oozing pus from blisters, or if you develop a fever. Prescription medications, such as antihistamines and corticosteroids, can help in such cases.

All material copyright MediResource Inc. 1996 – 2023. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source:

Tick trouble

Are ticks just a harmless nuisance?

Tick bites can present a temporarily annoying experience in the summertime. However, the additional possibility of catching Lyme disease is one more reason to take action against these bugs. Lyme disease is caused by a spiral-shaped bacterium called Borrelia burgdorferi, which is spread by the bite of ticks of the genus Ixodes, commonly known as deer ticks or black-legged ticks.

These ticks are tiny – about the size of a pinhead when immature – and grow only slightly bigger as adults. They crawl onto a person's skin from grasses and shrubs in wooded areas. The tick digs its mouth into the skin and feeds for 2 or 3 days before dropping off.

Although not necessarily confined to these specific areas, most cases of Lyme disease are reported in the northeastern US (from Massachusetts to Maryland), the north-central states (especially Wisconsin and Minnesota), and the west coast (particularly northern California). The disease is on the rise in the US, with approximately 30,000 cases every year. It's also on the rise in Canada: for example, the number of confirmed human cases jumped from 144 cases in 2009 to 2025 cases in 2017.

Signs of Lyme disease

A characteristic sign of Lyme disease is a skin rash that starts with a small red patch that gradually expands, often clearing in the centre to form a bull's-eye pattern. Other early signs and symptoms include chills, fatigue, fever, headaches, muscle and joint aches, and swollen lymph nodes .

If left untreated, late-stage symptoms can appear days to months after a tick bite, including dizziness, pain that spreads from one part of the body to another, arthritis, or difficulty thinking or remembering. Rarer, more severe symptoms can also appear such as loss of sensation, drooping of the face, heart problems, swelling of the brain, and spinal cord or eye infections.

Preventing tick bites

To avoid tick bites when hiking or camping in wooded areas:

  • If possible, stay away from tick-infested areas, especially in the spring, summer, and fall months.
  • Stay in the middle of hiking trails and try not to brush against grasses or leaves.
  • Wear light-coloured clothes to make it easy to spot ticks "hitching a ride" on you.
  • Wear closed shoes and long pants with the pant legs tucked into your socks or boots. As an extra precaution, put tape around the area where your pants and socks meet.
  • Wear a hat and a long-sleeved shirt for extra protection.
  • Spray your clothes and exposed skin with an insect repellent that contains 30% DEET (also effective at repelling mosquitos, which can carry malaria or West Nile virus), or treat clothes with the insect repellent permethrin, which kills ticks on contact. If using DEET, never spray it directly on your face or broken skin. For children under the age of 12, only DEET products with a maximum of 10% should be applied. Avoid daily use of DEET products for periods of over 1 month with this age group.

If you spend several days outdoors in areas that might contain ticks, inspect yourself daily once you're indoors. Check your skin carefully for ticks, and ask someone to check your scalp for ticks. If a tick has already latched on to you, don't panic. Even if the tick has bitten you, remember that not all ticks carry Lyme disease.

Removing ticks

The best way to remove a tick is with a tick-removing device or a pair of fine-point tweezers. Grasp it where its mouthparts enter the skin or, if that is not easily visible, grab it by its head (as close to your skin as possible) with the suggested removal tools. Pull the tick straight out firmly and steadily. Do not twist, squash, or crush the tick when you are removing it. Be patient, as proper tick removal takes time. If you notice that even though you've removed the head, some of the tick's mouthparts still remain in your skin, don't worry; the bacteria that cause Lyme disease reside in the tick's gut or salivary glands.

Do not squeeze the tick's body, do not apply petroleum jelly or alcohol, and do not use a hot match, nail polish, or other products while the tick remains attached. These actions could transmit the Lyme-disease-causing bacteria to you.

Once you remove the tick, place it in a container (e.g., a small jar with a lid) and record the date. You can use alcohol to kill and preserve it, or even just some wet paper towel, so you can take it to your doctor to check if it carried Lyme disease. Cleanse the affected area of your skin with an antiseptic (e.g., alcohol) or mild soap and water. Wash your hands thoroughly with soap and water. You should also have the tick bite examined by your doctor, especially if you develop a rash or flu-like symptoms.

Treating Lyme disease

For people who require treatment for a mild infection associated with Lyme disease, their doctor will usually prescribe an oral (by mouth) antibiotic for 14 to 21 days. These types of antibiotics include doxycycline, amoxicillin, or cefuroxime. The specific antibiotic used will depend on a person's medical history and medication allergies.

For people who require treatment for more severe infections associated with Lyme disease, their doctor will usually prescribe an intravenous (given through the vein) antibiotic (e.g., ceftriaxone, cefotaxime) for 2 to 4 weeks. On occasion, treatment with an oral antibiotic may be prescribed following treatment with an intravenous antibiotic.

If the tick is identified and removed within 72 hours of the bite, and assuming that no skin rash has appeared, your doctor may consider prescribing a single oral dose of doxycycline. This treatment can help prevent the rash from developing.

If you have Lyme disease, your doctor will determine the most appropriate treatment for you.

Overall, when you are travelling abroad, especially to developing and tropical countries, it is a good idea to speak with your doctor or pharmacist about how to protect yourself from diseases. Aside from watching what you eat and drink and protecting yourself from tick bites, you also have to watch for many other diseases, such as malaria, hepatitis, influenza, and yellow fever. Many of these diseases can be prevented with immunizations, so speak to your doctor or visit a travel clinic to see if you are at risk and what immunizations you and your family would benefit from.

All material copyright MediResource Inc. 1996 – 2023. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: