The staphylococcus aureus (staph) bacteria is a relatively common type of bacteria that usually doesn't cause any harm. However, a staph infection can occur when the staph bacteria enters body and multiplies.
What is a staph infection?
A staph infection occurs when the staphylococcus bacteria gets inside the body.
Around a third of people carry staph bacteria either on the surface of their skin or in their nose, and in most cases it does not cause any problems.
However, if it does enter the body the bacteria might multiply, which could lead to an infection.
There are many different types of staph infections, varying from boils to blood poisoning, and some are resistant to common antibiotics.
Most staph infections are caused by a bacterium called Staphylococcus aureus.
Who is at risk of a staph infection?
Anyone could develop a staph infection, but some people are more prone to staph infections than others. Those who are more likely to develop staph infections include:
It is important to make sure that staph infections are not spread to others.
- children and infants, who may develop an infection known as ‘school sores’ (impetigo) when they start attending daycare, preschool or school
- people with a weakened immune system, such as those with HIV/AIDS or those taking medications to suppress their immune systems
- people who regularly have medical equipment entering their body due to kidney dialysis, catheters, feeding or breathing tubes
- people who have been in hospital for a long time, due to contact with healthcare workers and proximity to other sick people.
How do I get a staph infection?
There are a variety of different types of staph infections. Staph infections occurring on the skin can be passed on by air, food, and contact with someone who has a staph infection or by touching a contaminated surface.
Staph bacteria may cause an infection if there is an abundance of it on the surface of the skin or if it enters the body through broken skin such as wounds, cuts or grazes.
You can also become ill from staph aureus food poisoning if the food you eat is contaminated by staph bacteria.
Skin staph infections
Staph infections on the skin include impetigo, wound infection, cellulitis and staphylococcal scalded skin syndrome (SSSS). You can learn more about this type of infection by reading our skin staph infection article.
Invasive staph infections
Invasive staph infections are far less common than skin infections, but usually more severe. There are many types of invasive staph infections and you can learn more by reading our invasive staph infections article.
How do I avoid getting a staph infection?
Skin staph infections
In most cases you can avoid developing a skin staph infection through basic hygiene. Always wash your hands thoroughly with soap and running water and dry them with a clean towel, or disposable paper towel.
In particular, wash your hands:
- before and after touching or cleaning an infected area
- after going to the bathroom
- after blowing your nose
- before handling and eating food
- after handling animals, including domestic pets.
If you live with someone who has a staph skin infection you may be able to avoid developing the condition by:
- not sharing any personal items with them such as toothbrushes, towels, clothes and linen
- washing your hands immediately if you come into contact with them
- ensuring their bedding and towels are cleaned daily, with hot water and bleach, before their infection disappears.
Invasive staph infections
If you are at risk of developing an invasive staph infection, it is important to have a healthy lifestyle – a healthy diet, regular exercise, minimising alcohol and avoiding smoking and illicit drugs.
Washing your hands thoroughly after going to the bathroom, before and after preparing food and after being in a crowded area can also reduce your risk of developing the condition.
Staphylococcal food poisoning
You can avoid food poisoning by ensuring that high standards of food hygiene are maintained throughout the cooking process.
When cooking keep hands, work surfaces and cooking utensils clean.
Wash hands before preparing food and after:
- going to the bathroom
- touching raw food
- touching bins
- handling pets.
Avoid handling food if you are ill, particularly with stomach problems or if you have open sores and cuts.
Cooking food properly
Meat should be cooked right through.
If you reheat food, make sure it is hot all the way through. Never reheat food more than once.
Chilling food properly
Food needs to be kept at the right temperature to prevent harmful bacteria from growing and multiplying. Food that needs to be refrigerated should always be stored in the fridge, which should be set at 0-5°C.
Always check the label on the packaging for the correct storage instructions.
Cooked leftovers should not be left out to cool for more than an hour before being put in the fridge or freezer.
Cross-contamination can occur when bacteria is transferred from one food (usually a raw food) to another food.
This can happen when the contaminated food is in direct contact with the other food, or when bacteria from contaminated food is spread through hands, utensils, work surfaces to other foods.
You can avoid cross-contaminating food by:
- always washing your hands after touching raw food
- storing raw foods separately to other foods
- storing raw meat in sealed containers and keeping the containers at the bottom of the fridge, so that it cannot leak onto other food
- using a separate chopping board for raw food and other food, or washing chopping boards thoroughly between uses
- cleaning utensils thoroughly after using them for raw food
- not washing raw meat or poultry, as washing may spray harmful bacteria around the kitchen.
Read more about preventing food poisoning.
How are staph infections treated?
Most skin staph infections are treated with a course of antibiotics.
Simple ones can be treated at home. Serious ones need to be treated in hospital with intravenous antibiotics and other treatments.
It is also important to make sure that staph infections are not spread to others.
Some Staph aureus is resistant to many antibiotics. It is known as Methicillin-Resistant Staphylococcus Aureus (MRSA), and can cause severe infections.
As a result of MRSA, doctors have become more cautious about prescribing antibiotics, and people are warned about taking them only if there is a clear need for the medicine. This will help reduce the risks of bacteria become resistant to antibiotics.
Read more about MRSA.
When should I get help?
If you suspect that you have a skin staph infection, it's important to see your doctor as soon as possible.
Severe skin staph infections, like staphylococcal scalded skin syndrome (SSSS), may need to be treated in hospital.
Invasive staph infections could be life threatening. If you have symptoms of an invasive staph infection, see your doctor as soon as possible or call triple zero (000) and ask for an ambulance.
Browse our links to trusted, online resources on staph infections to learn more about this topic.
Sources: NHS Choices, UK (Food Poisoning - Prevention, Staphylococcal infections), Queensland Health (Staphylococcus aureus infection), Virtual Medical Centre (Methicillin Resistant Staphylococcus Aureus (MRSA, Staph Infection))