About antibiotic resistance

Antibiotics are used to slow the growth of or kill bacteria that cause infections and illnesses. When antibiotic resistance develops, the antibiotics normally used may not work as well or fail completely.

Antibiotic resistance can happen naturally, but the inappropriate use of antibiotics in people, animals and plants is increasing the problem. Antibiotic resistant bacteria can spread easily among people and among animals.

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What antibiotic resistance is

Antibiotic resistance happens when bacteria that cause illness become resistant to the antibiotic drugs used to treat them.

The threat of antibiotic resistance is that infections (such as pneumonia, strep throat or infections associated with minor injuries) could become untreatable.

How antibiotic resistance happens

Antibiotic resistance happens naturally. To a certain degree, any antibiotic use can lead to antibiotic resistance. When bacteria are exposed to antibiotics, some bacteria with the ability to resist antibiotics survive.

Leading causes of increased antibiotic resistance are the overuse or inappropriate use of antibiotics in preventing or treating infections in people and animals.

Examples of antibiotic misuse include:

  • giving antibiotics to people and animals when they are not needed,
  • taking antibiotics in ways other than how they were prescribed,
  • self-medicating or antibiotic sharing,
  • taking antibiotics for an infection that is not caused by a bacteria.

How resistant bacteria spread

Anyone can get an antibiotic-resistant infection. Drug-resistant bacteria spread in the same ways as non-resistant bacteria.


Bacteria can spread between people in the following ways:

  • touching
  • coughing
  • sneezing
  • being exposed to bodily fluids (such as through unsafe sexual practices)

Contaminated surfaces

Bacteria can live and survive on surfaces for extended periods of time. You can pick up bacteria, including those resistant to antibiotics, when you touch everyday objects such as:

  • doorknobs
  • keyboards
  • utensils

Food, water and soil

You can be exposed to antibiotic resistant bacteria if you touch or eat foods that are not properly washed or prepared, such as:

  • meat, poultry and dairy products
  • fruits
  • vegetables

Contaminated water or soil can also infect us through direct contact or by putting bacteria into our food.


Bacteria can be passed from animals to people through direct contact with:

  • dogs, cats, reptiles and other pets,
  • petting zoo or farm animals, and
  • animal manure.

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International travel

If you travel internationally, you can pick up an infection not commonly found at home through contact with:

  • people
  • food
  • water
  • animals
  • contaminated surfaces

International travel may include trips for business, pleasure or even to have a medical procedure.

How to reduce the risk of antibiotic resistance

If you get sick and you think you might need antibiotics, consider the following advice:

  • Speak with your healthcare professional about the right treatment, and how to use antibiotics responsibly.
  • Take steps to learn how you can prevent antibiotic resistance for yourself and your family.

How antibiotic resistance relates to the food chain

Antibiotic resistance can spread through the food chain as well. Antibiotics are widely used in veterinary medicine and in agriculture. Animals receive antibiotic treatments in order to:

  • kill bacteria,
  • stop bacteria from growing and multiplying, and
  • promote animal growth.

Antibiotic resistance in animals makes bacterial treatments less effective for animals. It can result in stronger alternative antibiotics being used to treat animals. This can put people at risk of being exposed to other types of resistant bacteria.

Research is being done on the link between veterinary antibiotic use and the development of antibiotic resistance in humans.

For example, Salmonella is a common bacterium usually found in the intestinal tract of food animals. It can spread from animals to humans if raw animal meat is contaminated with the bacteria during slaughter and food processing. Resistant Salmonella is a dangerous and difficult to treat infection.

Resistant bacteria can be spread from animals to people through:

  • direct contact with animals, such as with pets, or handling or butchering livestock, or
  • eating raw, undercooked or unclean food, especially meat, poultry and dairy products.

Groundwater can also become contaminated with urine and manure from farm animals that have been exposed to antibiotics.

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