Antibiotic resistance is a global problem.  We continue to read news stories about superbugs, bacteria that are increasingly resistant to common antibiotics.  This resistance is causing new infections and making it difficult to treat others.  We all need to be responsible about the antibiotics we take – using antibiotics to treat viral infections like a cold or flu, using antibiotics too often, and not using antibiotics as prescribed are all contributing to the problem.  Use antibiotics wisely to help protect your health and the health of your family and community.

  1. What are antibiotics?
  2. Why don’t antibiotics work against colds, flu, coughs, or sore throats?
  3. So what do antibiotics treat?
  4. When should I see my doctor?
  5. When should I take my child to see a doctor?
  6. If there is a chance that I have a bacterial infection, shouldn’t I take antibiotics just in case?
  7. What is antibiotic resistance?
  8. Why should I be worried about antibiotic resistance?
  9. How can we stop the spread of resistant bacteria?
  10. How do bacteria develop resistance?
  11. Is there any good news?


1. What are antibiotics?

Antibiotics are medicines that treat infections caused by the approximately one hundred bacterial species that cause illness.  They have changed the way we treat many illnesses.

Penicillin has been used to treat bacterial infections and prevent death from infectious diseases since the 1940s.  This is just one of the many antibiotics used to treat bacterial infections. Antibiotics have added about ten years to the life expectancy of Canadians.

There are two main categories of antibiotics:

  • Narrow-spectrum antibiotics only kill a limited number of bacteria.  They can target and kill the bacteria that are causing your illness without killing other, good bacteria.  Narrow-spectrum antibiotics are usually prescribed when your doctor knows exactly what bacteria are causing your infection.
  • Broad-spectrum antibiotics work against many different bacteria, including some bacteria resistant to narrower-spectrum antibiotics.  They are prescribed when your doctor does not know exactly what bacteria are causing your infection or when your illness is caused by several different bacteria.

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2. Why don’t antibiotics work against colds, flu, coughs, and sore throats?

Antibiotics only treat infections caused by some bacteria.  They do not work for illnesses like colds and flu which are caused by viruses. Most sore throats and acute respiratory infections, and many earaches, are also caused by viruses.  The best way to get better from viruses is to rest, drink fluids, and stay home to avoid spreading the infection.  Talk to your pharmacist to find medicines to relieve your symptoms.

Preventing colds and flu can reduce unnecessary antibiotic use.  Washing your hands frequently in cold and flu season can reduce the risk of illness by as much as 50%.  The other major method we have to prevent viral illnesses is vaccines.  Vaccines prevent respiratory infections such as chickenpox, measles, and influenza.
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3. So what do antibiotics treat?

Antibiotics work on bacterial infections like pneumonia, strep throat, urinary and skin/wound infections.  Your doctor will know when it is appropriate to use antibiotics, and may take a throat swab, blood sample, or sputum sample before deciding how to treat your infection.
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4. When should I see my doctor?

Some earaches and sore throats are due to bacteria, but they are more likely due to a virus.  If you are feeling unwell, it is important to rest, even staying home from work if you are able.  Talk to your pharmacist about medicines that can relieve your symptoms.  There are medicines you can take to help the aches and pains, fever, congestion, and sore throat that are often associated with colds and flu.

You should consider checking with your doctor if:

  • Your illness is still getting worse after four days
  • You got better then worse with an increased fever
  • You have a recurrent fever over 38.5oC
  • You have rapid breathing or trouble breathing

If you’re ever worried that you are unable to cope with looking after yourself because of worsening illness, you should seek health care urgently.

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5. When should I take my child to see a doctor?

Normal healthy children get 2-6 separate infections per year and have had 15-30 by 6 years.  Consult your doctor if your child appears to be in pain, has a fever over 39oC, isn’t taking fluids, or has a rapid breathing rate (over 30 breaths per minute in children over 6 months).
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6. If there is a chance that I have a bacterial infection, shouldn’t I take antibiotics just in case?

Taking antibiotics when you don’t need them is not a good idea.  Over 90% of acute upper respiratory infections, including sinusitis, are caused by viruses, in which case, antibiotics will not help.  Additionally, over 95% of acute bronchitis cases (usually a cough with no sputum and a fever which lasts for 1-3 days) are due to viruses.  The cough may continue for up to 10 days following an episode of bronchitis; however, antibiotics will only make a difference when a bacterial infection is present.

Although antibiotics are generally safe, they may interact with other medication you are taking and may cause a number of side effects.  Disruption of the normal balance of bacteria in your body can lead to diarrhea or to a yeast infection. It is also possible to have an allergic reaction, which could be minor or severe.

The increase in antibiotic resistance is another reason not to take antibiotics unless they are necessary. The more we use an antibiotic, the more likely it is that bacteria will adapt to it.  This resistance can then be transferred to other bacteria. Some bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), are resistant to several antibiotics and are often called “superbugs.”  It is very difficult to treat these infections.
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7. What is antibiotic resistance?

Resistance occurs when an antibiotic is no longer effective at killing or limiting the growth of bacteria.  It can occur naturally (innate ability or genetic mutation), or can be acquired through previous exposure to an antibiotic or through contact with another organism that is resistant (transfer of resistance).

There are several ways that bacteria can resist the effects of antibiotics.  Some bacteria develop the ability to neutralize the antibiotic before it can harm them, others can change the antibiotic attack site so it cannot affect the function of the bacteria, and still others can pump the antibiotic out of the cell or prevent the antibiotic from getting into the cell.

Once bacteria are resistant, the infections they cause may not be cured or controlled by antibiotic treatment, or there may be few effective drug choices.  In some cases, these illnesses can lead to disability or even death.
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8. Why should I be worried about antibiotic resistance?

Antibiotics were once considered the solution to most infectious diseases.  Unfortunately, the misuse and overuse of antibiotics, combined with bacteria’s ability to resist treatment, mean that antibiotics are no longer as effective.  Antibiotic resistance is now a worldwide public health problem.

Almost all bacteria have developed some form of resistance, making antibiotics less effective at treating serious infections.  Someone with an infection that is resistant to a certain medicine can pass that resistant infection to other people, including family members, and coworkers.  In this way, a hard-to-treat infectious disease can threaten whole communities.  This can be especially dangerous for young children, the elderly, and people with weakened immune systems (e.g. individuals already in the hospital or chronically ill) who are more vulnerable.

In Canada last year, over 3000 individuals died from infections they contracted in a health care institution.
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9. How can we stop the spread of resistant bacteria?

Everyone has a role to play in using antibiotics responsibly.  Here are some tips:

  • Use antibiotics wisely: Don’t expect to get antibiotics every time you have a respiratory infection.  Know when it’s effective to use antibiotics and don’t use them for viral infections such as colds, flu, coughs, and most sore throats.  Even with some bacterial infections, you will usually recover just as quickly without antibiotics
  • Treat viral infections responsibly: Don’t pressure your doctor for antibiotics when you have a viral infection.  Instead, talk to your doctor or pharmacist about ways to feel better when you are ill.  There are medicines you can take to relieve your symptoms.
  • Take antibiotics exactly as prescribed: If you are prescribed antibiotics, follow the dose and schedule instructions exactly.  Finish all the antibiotics you are given, even if you start to feel better.  Do not share them with someone else or save them for another time.
  • Never take antibiotics without a prescription: In many countries, it is possible to get antibiotics without a prescription.  Using antibiotics when you don’t need them is a significant contributor to antibiotic resistance and will not make you feel better.
  • Stay at home if you’re sick: Prevent the spread of germs by staying at home when you’re sick, washing your hands frequently, and practicing good hygiene.

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10. How do bacteria develop resistance?

The widespread use of antibiotics around the world promotes the development of antibiotic resistance.  Bacteria can develop drug resistance when:

  • Antibiotics are used too often or without a purpose (e.g. to treat a viral infection)
  • An antibiotic is stopped too early
  • The dose or schedule instructions for an antibiotic are not followed

When antibiotics are used too often or used improperly, they can kill the vulnerable bacteria in the body, but leave some of the resistant ones to grow and spread.  Resistant bacteria can persist in the body and cause infection in the same person, or spread to other people and make them sick with a bacteria that is more difficult to treat.

Bacteria are very resilient.  They can:

  • Neutralize antibiotics before they kill the bacteria
  • Change the antibiotic attack site so it cannot affect the bacteria
  • Pump the antibiotic out of their cells
  • Prevent the antibiotic from getting into their cells

These techniques allow resistant bacteria to thrive in the presence of antibiotics.
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11. Is there any good news?

Because antibiotic misuse is one of the causes of antibiotic resistance, it is possible to slow or reverse resistance by being more responsible about the way we use antibiotics.  This will help ensure that antibiotics we now have continue to be effective while researchers work to develop new antibiotics or other treatments for serious bacterial infections.

Using simple infection control practices, it is also possible to prevent many infections in the first place:

  • Wash your hands to reduce your risk of becoming ill
  • Ensure you and your children are up to date on your vaccinations
  • If you are sick, stay away from others as much as possible, to reduce spreading your infection

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