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MRSA has often been featured in the news. The antibiotic-resistant superbug seems to spread through healthcare settings like wildfire. Around 1 in 3 of us carry the bacteria harmlessly on our skin, most commonly in the nose. Whilst in most cases it’s innocuous, if a person has broken skin, there is a heightened risk that the organism can get to other areas via the bloodstream and cause more serious infections.
What is MRSA?
MRSA – the short name for methicillin-resistant Staphylococcus aureus – is a type of bacteria that is resistant to many types of commonly used antibiotics including methicillin and penicillin-type antibiotics. This makes it much harder to treat compared with other bacterial infections caused by Staphylococcus aureus such as skin abscesses, boils, impetigo and wound infections.
Often, MRSA is contracted in hospitals or other healthcare settings such as care homes and nursing homes. In these cases, the bacteria often get into the body through broken skin and then multiply, causing dangerous symptoms. Due to its resistance to some antibiotics, treatment options for MRSA infection are more limited. It can lead to sepsis (an extreme infection response in the body) if it is not treated.
What does MRSA stand for?
MRSA stands for methicillin-resistant Staphylococcus aureus. Essentially, MRSA is a type of Staphylococcus aureus infection that does not respond to the antibiotics that usually treat such infections. This is what gives it the moniker ‘superbug’.
There are different types of MRSA, with infections classified as either hospital-acquired MRSA (HA-MRSA) or community-acquired MRSA (CA-MRSA).
Hospital-acquired MRSA is an infection that is contracted in a healthcare setting such as a nursing home or hospital. This type of MRSA is often contracted through direct contact with contaminated hands or an infected wound. It can also be contracted through poor sanitisation with contaminated surgical instruments or bed linen. It can cause significant problems including septicaemia and pneumonia.
Community-acquired MRSA is often transmitted via direct personal contact with someone who has an infection or through close contact with a wound that is infected. This type of MRSA can also develop as a result of poor hygiene and not washing your hands properly.
What causes MRSA?
As mentioned, MRSA is caused by the Staphylococcus aureus (S. aureus) bacteria. However, unlike the standard variety of S. aureus bacteria, this type is highly resistant to lots of commonly used antibiotics such as methicillin, penicillin and amoxicillin.
Staphylococcus aureus (S. aureus)
S. aureus is what’s called an “opportunistic bacterial pathogen”. It is associated with colonising the mucosal surfaces and the skin without causing harm. Around a (this means they have been “colonised” with S. aureus).
Staphylococcus aureus can cause disease if it enters the body through broken skin or during procedures using invasive medical instruments. These illnesses can be mild or life-threatening.
S. aureus can cause:
- Skin infections.
- Wound infections.
- Infected eczema.
- Joint infections.
- Endocarditis (infections of the heart valves).
- Osteomyelitis (bone infections).
- Bacteraemia (bloodstream infection).
Staphylococcus aureus can also cause food poisoning as it produces toxins which may contaminate food.
The majority of strains of S. aureus respond to typically used antibiotics, meaning the infections are treated effectively. However, some strains of S. aureus are resistant to the more commonly used types and require alternative antibiotic treatment. It is these strains that are methicillin-resistant and are what we know as MRSA.
MRSA is a cause for concern due to its resistance compared with other types of S. aureus infection. Not only that, but it has also become particularly linked to hospital-acquired infections.
Who is at risk of MRSA?
Anyone can develop an MRSA infection, but some people are more at risk of serious infection than others.
There are several factors that increase a person’s risk of developing MRSA infection:
- People in hospital or those who have had medical procedures recently including dialysis or surgery. This is because, in hospital, they are in close contact with other patients and healthcare workers who may carry the bacteria from patient to patient.
- Immunocompromised people. People with cancer, HIV/AIDS, organ transplant recipients or other chronic immune-deficiency illness are more susceptible to MRSA infections as their bodies are less able to fight off infections.
- People with skin conditions such as psoriasis or eczema, or those with skin injuries, cuts or abrasions. These people are more at risk of developing MRSA because the bacteria are more easily able to enter the body through open wounds or broken skin.
- Those who participate in contact sports. People who participate in contact sports such as boxing, wrestling and rugby are at an increased risk of developing MRSA infection as the bacteria can spread through skin-to-skin contact or by using contaminated equipment.
- People who live in crowded and/or poor living conditions including military barracks and prisons. This is because the bacteria spread more easily in these kinds of environments.
- People who have been treated previously with antibiotics like clindamycin or ciprofloxacin. This is because these types of antibiotics kill off normal bacteria in the body, even the harmless kind. This gives MRSA more of an opportunity to take hold.
- Family members, carers or close contacts with someone who has an MRSA infection are also at an increased risk.
Despite all of the risks outlined above, we must reassure that not everyone with these risk factors will develop an MRSA infection. What’s more, someone who doesn’t fulfil any of the risk factors can also become infected. Good hygiene practices, proper wound care and regular handwashing can help reduce the risks of infection.
There are some risk factors which are more apparent for hospital-acquired MRSA and community-acquired MRSA. Those more at risk of developing HA-MRSA are people who have recently been hospitalised (within the last three months or so), those who regularly have haemodialysis, immunosuppressed individuals, and those who live in nursing homes, care homes and sheltered accommodation.
For community-acquired MRSA, the risk factors include the sharing of towels, razors, or sports equipment with other people, those who participate in contact sports, nurses and carers, and those who live in crowded and/or unsanitary conditions.
What are the symptoms of MRSA?
As explained, MRSA is a type of bacterial infection – one that does not respond well to commonly used antibiotics. Having said that, the symptoms of MRSA infection are not the same in everyone. The symptoms will depend on where the infection is located and whether it has penetrated deep into the body, organs or bloodstream.
Having MRSA on your skin doesn’t cause symptoms. Those who have it on their skin (around one in three people) are usually not aware of it unless they’ve been tested for it (often due to being admitted to hospital).
However, if MRSA gets deep into the skin, it can cause symptoms such as:
- Redness (although if you have darker skin, this is often not as noticeable).
MRSA can cause lesions on the skin like boils and painful bumps. These are often filled with fluid or pus.
As an MRSA infection takes further hold and enters the bloodstream, it can then cause other symptoms:
- Aches and pains.
- Low blood pressure.
MRSA can also cause pneumonia, resulting in a cough, shortness of breath, chest pain and fever. If the infection is in another part of the body, different symptoms may occur. For example, if in the urinary tract, urinary symptoms such as haematuria (blood in the urine), dysuria (painful urination) and lower abdominal pain may be experienced.
However, even if you carry MRSA, you may well not experience any symptoms. It is important to seek medical help and support if you feel like you may have an MRSA infection so that you can be diagnosed and get the right treatment.
MRSA is typically diagnosed through a combination of taking a person’s medical history, physical examination and laboratory testing. However, many people’s MRSA diagnoses come from a hospital screening test.
MRSA screening is a process that is used to detect whether MRSA bacteria are present in those who are at a higher risk of either carrying or developing MRSA infections. Often, screening is done as a preventative measure and to identify carriers who can then be treated to prevent the infection from spreading further.
Screening is often recommended for:
- People who have been in hospital for a long period of time.
- People who have been in close contact with someone who has a known MRSA infection.
- Healthcare workers who are often exposed to MRSA in their workplace.
- People who are going to have a surgical procedure.
- People who have regular dialysis treatment.
Normally, this screening is undertaken at a pre-admission check but it can also take place at a GP surgery. A nurse usually runs a cotton bud over particular areas of skin such as the groin, underarms or in the nose and this is passed on to the laboratory for testing. The results of these screening swabs are usually available within a couple of days or less. If your screening test is positive, you will be informed and treated, particularly if you are due to have a procedure in hospital.
Often, healthcare providers will ask someone about their symptoms and their medical history to determine if they are at risk of contracting MRSA. A physical examination also follows to look for any skin lesions or parts of the body that may be infected.
Medical professionals are often able to diagnose likely MRSA infection based on these two elements but this must also be confirmed by laboratory testing to be clear on the type of infection present and the treatment needed.
Culture and sensitivity testing
To diagnose MRSA, a sample of pus, blood or other bodily fluids is often collected and sent to the laboratory for culture and sensitivity testing. The growth of the bacteria determines which type of bacteria is present whilst sensitivity testing determines the types of antibiotics that should work to clear the infection.
There are several types of cultures that can be grown in the lab including cultures from sputum, urine and blood.
Polymerase chain reaction (PCR) testing
Many of us are familiar with the acronym ‘PCR’ thanks to our experiences with Covid testing. PCR tests can be used for different infections, including testing for MRSA. The PCR test can assess whether there is any MRSA DNA within the sample provided. PCR testing provides much quicker results than culture and sensitivity testing.
How to prevent MRSA
MRSA presence is common. Infection isn’t as common (otherwise a third of us would be suffering from an infection at any one time!) but it is a risk. Doing everything you can to prevent an MRSA infection is vital, particularly if you’re one of the more ‘at risk’ people identified earlier.
Here are a few ways to help prevent MRSA infection:
1. Practise good hygiene.
This means washing your hands often with soap and water, especially before eating and after using the toilet. Keeping cuts, scrapes and other skin wounds clean and covered is also essential.
2. Avoid close contact with MRSA-infected people.
If your granny has a known MRSA infection, try to avoid close contact until their infection has resolved. This may be difficult if you are a caregiver for that person, however.
3. Keep personal items clean.
Don’t share your personal items with others. These items include razors, towels or inner clothing.
4. Keep surfaces clean.
Clean any surfaces regularly with antibacterial cleaner. Pay particular attention to worksurfaces, handles, keyboards, phones and computer mice.
5. Use antibiotics appropriately.
This may seem like a strange one. However, overusing antibiotics when they’re not really needed is what leads to antibiotic-resistant bacteria such as MRSA. The bacteria evolve to be able to withstand the antibiotic onslaught and they multiply rapidly, meaning our risks of infections are increased.
6. Follow the guidelines set by healthcare facilities.
If you’re a healthcare worker, patient or a visitor, you must follow all the infection control guidelines outlined by the facility and notify providers if you have signs and symptoms of infection.
7. Get vaccinated where possible.
Although there is no vaccine for MRSA, other vaccines can help reduce our likelihood of contracting the infection. For example, the pneumococcal vaccine prevents infections that lead to pneumonia, which is a known risk factor for contracting an MRSA infection.
It is important to note that even if you follow these preventative measures to the letter, you may still acquire an MRSA infection. But the more you follow these recommendations, the less likely you are to become infected.
What are the complications of MRSA?
As mentioned, many people carry MRSA bacteria around on their skin with no problem. However, being exposed excessively can have serious and life-threatening complications. Complications of MRSA infection can vary depending on where the infection is located as well as a person’s overall health and age.
Here are some of the more common complications of MRSA infection:
If MRSA bacteria enter the bloodstream, this can cause septicaemia, a potentially life-threatening condition.
Pneumonia is a lung infection that can be severe, particularly in people with weakened immune systems or in elderly people.
Endocarditis is an infection of the inner lining of the heart that can have serious consequences.
Osteomyelitis is an infection in one or more bones. Because of the location, osteomyelitis can be a difficult infection to treat.
- Skin and soft tissue infections
Cellulitis, abscesses and necrotising fasciitis are all severe skin infections that can spread rapidly and cause tissue and skin to die off. Often, the only treatment is amputation of the affected area.
If you have a confirmed diagnosis of an MRSA infection or suspect you may have contracted it, seeking medical attention is essential. Early diagnosis and subsequent early treatment can help prevent severe, life-endangering complications.
How to treat MRSA
As you may have deduced by now, treating MRSA infections with typical antibiotics doesn’t work. However, there are some treatments that are effective in getting rid of the bacteria.
Treating MRSA detected on screening
If your MRSA infection was detected as part of routine screening, you may need treatment to ‘decolonise’. This normally involves applying antibacterial cream to the inside of the nose three times each day for around five days as well as washing with special antibacterial shampoo for the same period. Changing clothes, bedding and towels each day is also advised, with laundry being washed separately from everyone else’s and washed at a high temperature.
Treating an MRSA infection
To treat an acquired MRSA infection, specific antibiotics that work for MRSA infections are prescribed. These are often given as tablets but may also be via injection or even intravenously in serious infections. This treatment lasts from a few days up to a few weeks.
In hospital, those with MRSA are isolated from other patients and healthcare assistants are careful to wear personal protective equipment (PPE) such as aprons, gloves and facemasks. Visitors may also be asked to wear PPE but are normally still permitted to visit.