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Frequently asked questions (FAQ) about HCAI's

What are Healthcare Associated Infections (HCAI)?

Healthcare-associated infection (HCAI) refers to infections that occur as a result of contact with the healthcare system in its widest sense - from care provided in your own home, to general practice, nursing home care and care in acute hospitals. The term has recently been coined in recognition that increasingly complex procedures are undertaken outside hospitals. Previously, when most complex healthcare was hospital based, the term hospital acquired infection was used.

What does the term hospital-acquired infection mean? 

Hospital-acquired infection (HAI) (also known as nosocomial infection) has a strict definition. It refers to an infection that develops in a patient 48 hours or more after admission to a hospital. Infections that occur within the first 48 hours are considered to have been picked up in the community and were incubating prior to admission. These are then referred to as community-acquired infections.

What does the term community-acquired infection mean?

Community-acquired infection (CAI) is any infection that a patient has when they come into hospital or occurs within the first 48 hours of admission. In this latter case, it is assumed that the patient was already incubating the infection, which they picked up in the community prior to admission.

The 48 hour cut-off is somewhat arbitrary as infections have variable incubation periods. Nevertheless, some standard definition is useful when considering likely sources of infection and 48 hours has remained the standard for many years.

Is healthcare associated infection all due to MRSA?

No, although most of the news headlines are about MRSA healthcare associated infection can be due to a variety of organisms that happen to be picked up from a healthcare setting. MRSA can also sometimes be acquired in the community. Further information on specific topics related to healthcare associated infection (HCAI) is available on this website.

The Top Ten Blood Stream Infection Surveillance (bacteraemia) surveillance provides some insight into the burden of infections dealt with by NHS Trusts/Health Boards in Wales and reflects both community and healthcare associated infections. It can be seen from the tables of blood stream infections that other organisms can cause healthcare associated infections and that MRSA is not the most common infection encountered in our hospitals.

Why are HCAI such a big problem in the modern health service?

From the earliest days of healthcare, organisms have found opportunities to cause infection at sites of wounds and in weakened patients fighting other diseases. As the health service has modernised with increasing knowledge, technology and innovation you might have expected infections to disappear. However the increasing numbers of invasive treatments and powerful drugs that are now available to us not only improve the survival rates for many cancer and trauma patients for example, but also carry an increased risk of associated infections.

HCAI is a problem because the development of infections in association with healthcare increases the time a patient takes to get better from the surgery or other treatment that was first given and they can lead to severe disability or death in some cases. From the healthcare service point of view patients who remain in hospital longer due to HCAI means that other patients cannot be treated as quickly and outbreaks of infection can cause severe disruption to a hospital or community healthcare service.

What impact do they have?

On the basis of a survey carried out in 2006, it is estimated that about 6% of patients in hospital, at any given time, have an infection that they picked up in hospital. Currently a further survey is being carried out in Wales and other parts of the UK to bring this data up to date. It is also thought that up to 5000 patients die of hospital acquired infection every year in England & Wales combined (source: The management and control of hospital acquired infection in acute trusts in England (NAO, 2004))

The impact of healthcare associated infections is felt by patients, their families and carers, and the health service itself. Patients may endure severe and /or chronic illness, pain, anxiety, longer stays in hospital, a reduced quality of life, loss of earnings and sometimes even death.

The health service has to bear the cost of diagnosis and treatment of these infections, the extended length of stay, which often results, and the use of more expensive treatment that may be needed. Infection Control services must also be paid for and bed / ward closures and cancellation of operations / admissions that can result from these infections, are also a hidden burden for the health service.

Why do HCAI occur?

There are several reasons why HCAI occur:

  • Increasingly complex and toxic treatments are now available to us to treat cancers, leukaemia and other diseases. These advanced treatments improve patient survival, but the treatments weaken the body's defences against infection and hence patients undergoing these treatments occasionally develop infections.
  • Increasingly complex surgical operations such as organ transplants are now available as a treatment option. The success of these operations is dependent on the use of drugs that deliberately weaken the body's defence system. Whilst this is necessary to prevent rejection of the donated organ, they make the body more vulnerable to infection.
  • The medical advances seen in intensive care have saved numerous lives, however the use of various support treatments such as kidney dialysis and prolonged breathing support increase the patient's risk of developing infections.
  • Medical devices such as urinary catheters and intravenous lines are frequently used and sometimes need to be left in place for long-term use. These medical devices breach the normal body defences and again provide an entry point for infection.
  • Antibiotics are used to treat infections and also to stop infections developing (prophylaxis). Over-use of antibiotics can result in the development of resistance to antibiotics in some organisms. This will make them more difficult to treat with common antibiotics.
  • Patients with chronic diseases, such as diabetes or kidney failure, can be at more risk of infection in general, hence in the context of receiving healthcare they will be at a higher risk of acquiring infections.
  • Patients of advanced age can be at more risk of infection in general, hence in the context of receiving healthcare they will be at a higher risk of acquiring infections.
  • Increased patient movement around hospitals and between hospitals due to the current pressures on hospital beds and increased specialisation provides new opportunities for spread of infections around the hospitals.
  • Poor standards of hygiene in healthcare settings and the lack of isolation facitilities can also contribute to the development of infections.
  • HCAI are known to pass from person to person on hands, hence handwashing is one of the main defences healthcare workers have in limiting the spread of HCAI. When handwashing is not performed due to inadequate facilities or pressure of time, the risk of passing on infections is increased.

Where in the body are HCAI seen?

The urinary tract is the commonest site for a HCAI to develop, closely followed by infections of the chest (lower respiratory tract):

The main sites of healthcare associated infections


pie chart

Source: The management and control of hospital acquired infection in acute trusts in England (NAO, 2004)

Are HCAI preventable?

It is probably impossible to eradicate healthcare associated infections completely. It has however been estimated that a proportion of healthcare associated infection can be prevented. It is thought that about 15% - 30% could be avoided by improved practices and better application of existing knowledge.

What are the Welsh Government and the NHS doing about HCAI?

To support the reduction of HCAI in Wales the Welsh Government launched the "Healthcare Associated Infections – A Strategy for Hospitals in Wales"  in September 2004, the first document in a series of guidance documents aimed at the health service in Wales. The strategy for reducing healthcare associated infections in the community will follow and through these strategies the health service in Wales will be guided to reduce the burden of healthcare associated infections.

Other initiatives related to healthcare associated infections that are currently in place in Health Boards in Wales are the Clean Your Hands Campaign, and from June 2006 an e-learning package will be launched in Wales to provide education in Infection Control for all members of staff in the NHS in Wales.handwashing

Individual Health Boards in Wales are implementing the recommendations of the strategy and all have specialised infection control staff who advise the Health Boards on the management and prevention of infections and also develop various other Infection Control programmes and initiatives, details of which can be found via the individual Trusts.

There is a comprehensive Surveillance Programme for infections in Wales, which provides Health Boards with information about rates of various infections in their Health Board, highlighting for them potential areas for investigation and action.

What can you do to help?


  • Ensure that hospital staff are fully aware of any infections you may already have, particularly if you are being treated with antibiotics currently or very recently.
  • Complete any recommended courses of antibiotics and do not expect antibiotic treatment for common viral conditions such as sore throats, colds and coughs.
  • Be aware of your own handwashing practices and don't feel afraid to question medical and nursing staff whether they have washed their hands (Clean your hands campaign) before examining you.
  • Follow advice given with regard to wound dressings and handling of medical devices such as urinary catheters and intravenous catheters.
  • Advise your friends and relatives that if they are ill, and particularly if they have diarrhoea, vomiting or flu not to visit the ward if possible.
  • Attempt to limit the numbers of visitors at any given time and follow ward advice with regard to food, flowers and laundry.


  • Try not to visit relatives/friends in hospital if you are currently or have recently been unwell, particularly with diarrhoea, vomiting or flu.
  • Follow advice given in the hospital with regard to the numbers of visitors allowed at any given time.
  • Follow advice given in the hospital with regard to food, flowers and laundry.
  • Use alcohol gel/handwashing facilities provided for visitors use.


Last updated: 08/02/2012