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Cold and flu

Learn how to protect yourself and others from cold and flu and how to take care of yourself!

Source: Health Services

What are cold and flu?

A cold and the flu (influenza) are infections that affect the respiratory tract, which is made up of the breathing organs that include the nose, throat, and lungs.

A cold is among the most common infections in humans: adults have 2-4 colds per year on average (children have 6-8). Colds are not serious infections—nor are they life-threatening—but their impact is significant, especially on the economy. Colds are a leading cause of missed days of work and school. Canadians spend millions upon millions of dollars each year on cold treatments, and millions of dollars from the health care budget are spent on unnecessary physician visits.

The flu is different from a cold, although they do share some symptoms (see "Signs that you have a cold or the flu" below). Unlike a cold, the flu can be life-threatening.  The Public Health Agency of Canada estimates that each year 20,000 people go to the hospital because of the flu and 2,000 to 8,000 people die from it. The elderly, young children, and people with a chronic illness (e.g. heart disease, cancer, and diabetes) are most vulnerable to the serious consequences of the flu.

The good news is that there are steps you can take to prevent catching a cold or the flu as well as ways to prevent spreading them if you do become infected.  See below for information on how to protect yourself and others.

Signs of cold or flu

Each of us experiences a cold or the flu in our own way. Factors such as your age, how healthy you are and the strength of your immune system can all affect the signs you will experience and how intense they will be.

In general, symptoms are usually the worst 2-3 days after a person becomes infected and can last for 7-10 days. Although not common, some symptoms can last for up to 3 weeks.

Typical signs of a cold include:

  • Runny or stuffy nose
  • Sneezing
  • Sore or scratchy throat
  • Slight body aches
  • Cough

Some of the symptoms of the flu are similar to a cold such as a sore throat, cough and runny nose.  However, the following signs are typical of the flu, but not a cold:

  • Very high fever that comes on quickly (lasts usually 3 or 4 days)
  • Fatigue and weakness
  • Severe aches and pains

The signs of the flu tend to come on quickly. You may feel fine first thing in the morning, but by late afternoon you are feeling terrible. The signs of a cold tend to appear gradually.

Symptom Cold Flu Allergy
Fever Rare Usually yes, and can be high, 102-104° F Never
Headache Rare Yes Rare, but yes if developing a sinus infection
Stuffy/runny nose Yes
May start out clear and turn cloudy or green
Drainage can be cloudy or green
Drainage is clear
Cough Yes Yes, maybe severe Sometimes, usually due to post nasal drip
Sore throat Common Sometimes Sometimes, associated with post nasal drip
Fatigue, aches/pains Sometimes Very common Rare
Vomiting/diarrhea Rare Sometimes Never


Treating a cold or flu

What works

Despite your best prevention efforts, you may still get a cold or the flu. Unfortunately, there is no cure for either of these illnesses.

Many people believe that antibiotics can cure a cold or the flu or make them feel better. Antibiotics are drugs that are used to eliminate bacteria. Antibiotics are useless at treating infections caused by a virus, such as a cold or the flu. Using antibiotics when they are not needed promotes antibiotic resistance, which is the ability of bacteria to survive when exposed to antibiotics. This makes antibiotics less effective. Do not pressure your doctor for a prescription for antibiotics.

Since there is no cure for a cold or the flu, and there are no medications a physician can prescribe to cure them, there is no need to see a health care provider if you get either of these illnesses. However, there are instances when complications arise that might require medical attention. Consult "When to see a doctor" below for information. A doctor may prescribe an antibiotic for a complication that is caused by a bacteria (i.e. secondary bacterial infection). Anytime you are prescribed an antibiotic it is important to follow the doctor's instructions.

Because a cold and the flu are self-limiting illnesses, treatment focuses on relieving the problematic symptoms, such as cough, sore throat, nasal congestion or fever. If the symptoms are not particularly bothersome for you, there is no need to do anything. In fact the symptoms of a cold or the flu—such as fever—are the body’s way of getting rid of the virus.

If you have a cold or the flu you should rest and drink plenty of fluids, such as water or clear soups. Fluids prevent dehydration and they help loosen mucous. If you smoke you should stop—or at least cut down—as it can make symptoms worse. (You could even use this as a starting point to explore quitting for good!!!). For specific bothersome symptoms, try the following:

  • Sore throat: Gargling with warm salt water can provide temporary relief. Dissolve ½ teaspoon of salt into one cup (250 ml) of warm water. Gargle with a big sip of the the solution for 5-10 seconds and then spit it out. Repeat until the cup of warm salt water is finished. Do this every every 2 hours, or more often if possible. Throat lozenges may also help.
  • Fever: Acetaminophen (e.g. Tylenol).
  • Pain: You can use over the counter pain medications such as acetaminophen, Ibuprofen (e.g. Advil) or ASA (e.g. Aspirin).
  • Nasal congestion: Saltwater washes (also called nasal lavage or irrigation) using a bulb syringe or neti pot can provide comport by loosening mucus and moistening the skin in your nose. Decongestant sprays and pills can help relieve nasal congestion but they should not be used for more than 3 days as they can make inflammation worse.

What doesn’t work

Over the years, numerous attempts have been made to discover ways to cure a cold or the flu or to reduce their severity or length of symptoms. Many of these have been researched: the findings are not encouraging. There is no evidence to suggest that Echinacea, large doses of vitamin C, zinc lozenges or other supplements can cure a cold or the flu or lessen their severity or duration. And, as we mentioned earlier (but it is worth repeating); antibiotics are useless against the viruses that cause a cold or the flu. Do not pressure your doctor to prescribe antibiotics. 

Antihistamines are not effective for sneezing and nasal congestion that result from a cold or the flu.

When to see a doctor

Complications from a cold are rare. However, a cold can make you more susceptible to infections such as sinusitis, bronchitis, or ear infections. The most severe complication of the flu is pneumonia, which can be fatal especially in vulnerable people such as the elderly and those with a chronic illness. You should consult a doctor if you notice any of the following:

  • Symptoms that don’t get better after 10 days or get worse instead of better
  • Fever of 103ºF (39.4ºC) or higher
  • Fever along with sweating, chills and a cough with colored phlegm (mucous)
  • Severe sinus pain in your face or forehead
  • Severe headache
  • Neck stiffness
  • Thick yellow/green drainage from your nose
  • Difficulty breathing or shortness of breath
  • Pressure or pain in the chest
  • Sore throat and fever with no other symptoms
  • Severe or persistent vomiting

If you get cold or the flu and have a health condition that makes it more likely that you will have a complication (e.g. asthma, immune deficiency), you should see a nurse to be evaluated.

How to prevent spreading or catching a cold or the flu

Prevent spreading a cold or the flu

There are two main things that you can do to prevent spreading a cold or the flu.

  1. Wash your hands regularly and properly.
  2. Always cover your cough or a sneeze, but not with your hands. Obviously, if you cough or sneeze into your hands the viruses get on them and you spread them to everything you touch. Instead, cough or sneeze into a tissue. If a tissue isn’t available, you can cough into the fold of your elbow or even into your armpit. For a humorous look at effective coughing and sneezing techniques watch the Cough Safe video.

Because cold and flu symptoms become apparent a short time after you become infected, you may have the viruses in your respiratory tract and not even know it. Therefore, it is always important for you to wash your hands regularly and properly and to cover your cough (but not with your hands).

Prevent catching a cold or the flu

There are several measures you can take to prevent getting a cold or the flu. Because the viruses that cause them are predominantly spread by hands, it is not surprising that the two most important prevention strategies involve the hands.

The most important thing you can do is to wash your hands regularly and properly. Proper hand washing removes the germs from your hands so that you don’t spread them.A second prevention strategy is to avoid touching your hands to your face. You can have millions of cold or flu viruses on your hands, but as long as they don’t get near your respiratory tract you won’t get a cold or the flu. We regularly touch our face: We scratch our nose, pick stuff out of our teeth, burst a pimple, rest our head in our hands, and more. Most people are not conscious of touching their face, so it can be difficult to stop doing it. However, it is well worth getting into the habit. Think of your hands as always being contaminated (except of course, when you have just washed them).

If you need to touch your face—to get an eyelash out of your eye for example—then wash your hands first. You should also wash your hands before eating. If you want to scratch your face, use the sleeve of your shirt. Don’t scratch your face with an object like a pen as it may be contaminated with viruses. In fact, you should generally avoid putting objects to your face. Although indirect contact is the main way colds and the flu are spread, they can also be spread directly through droplets. If you are near someone who is not covering their sneeze or cough, then cover your mouth and nose and move away. The droplets fall to the ground but they can still be in the air for 1-2 meters around the person.

Besides these measures, there exists a vaccine to prevent the flu. Each year a new vaccine is produced that protects against the most serious strains of the flu. The flu shot is available at Concordia Health Services. There is no vaccine to prevent a cold.

Other prevention strategies

The strategies mentioned above are the most effective ways to prevent getting a cold or the flu. However, adopting positive health behaviours can reduce your chances of getting them. These behaviours may strengthen your immune system. Healthy living can make your body stronger, which can reduce the length of time you have a cold or the flu as well as reduce the severity of the symptoms. However, leading a healthy lifestyle and having a strong immune system does not mean you will never get a cold or the flu. Behaviours that can reduce your risk include:

  • If you use tobacco...quit. Smoking has a negative impact on all of the body’s systems, including the immune system. On average, smokers get more colds and the flu than those who don’t use tobacco. Also, smokers may experience more intense symptoms or the symptoms may last longer. There are numerous other benefits to quitting smoking.
  • Manage your stress. Stress, especially if it is prolonged, can weaken the immune system.
  • Eat healthfully. A strong immune system requires building blocks that come from a healthy diet.
  • Get adequate and restful sleep. Sleep deprivation—especially if it is prolonged—can negatively affect immune function.
  • Enjoy regular physically activity. Research has identified numerous benefits associated with regular physical activity, including a decreased risk of infectious diseases.

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