Infection Prevention and Control

Introduction[edit | edit source]

According to the World Health Organization (WHO), infection prevention and control (IPC) is a scientific approach and practical solution designed to prevent harm caused by infection to patients and health workers. It is a subset of epidemiology, but also serves an essential function in infectious diseases, social sciences and global health[1].

Effective IPC is a public health issue that is fundamental in patient safety and health system strengthening. The prevention of healthcare-associated infections (HAI), epidemics (including the 2013-2016 Ebola virus disease outbreak), and pandemics of international concern (For Example; 2009 flu pandemic and the coronavirus disease 2019) are rooted in effective IPC measures[2]. A guiding principle on WHO's Core Components of IPC is that "access to health care services designed and managed to minimise the risks of avoidable HAI for patients and health care workers is a basic human right"[2].

Strengthening global IPC is essential to combat HAI, antimicrobial resistance, and to respond to disease outbreaks. A study published in 2021 looked at the WHO's Core Components of IPC and found that most participating countries have IPC programmes and guidelines in place, however few have set aside the necessary resources to support the programmes. There is a need to move from the planning stage into the implementation and monitoring stages, particularly in low-income countries[3].

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The Spread of Infectious Disease[edit | edit source]

An infection is defined as the successful transmission of pathogenic microorganisms, such as bacteria, viruses, parasites or fungi that are spread:[4][5][6][7]

  • Directly:
    • From person to person
    • Through respiratory droplets (for example, coughing or sneezing)
    • Through body fluids
    • Direct exposure to infectious agent in environment
    • During childbirth from mother to foetus (transplacental/perinatal)

  • Indirectly:
    • Biological - Vector or Intermediate host (for example; Zika Virus)
    • Mechanical - Vector or Vehicle  (for example; Plague - transmission of Yersinia Pestis by fleas)
    • Airborne (for example, Tuberculosis)

Epidemiological Triad[edit | edit source]

In humans, infections occur when an infectious microorganism enters the body, multiplies, and leads to a reaction in the body and potential infectious disease. The spread of infectious disease requires three variables, known as the epidemiological triad[8]:

  • The Agent - The microorganism that causes the infection and can be in the form of bacteria, viruses, parasites or fungi
  • The Host - The target of the disease
  • The Environment - The surroundings and conditions (these are external to the host)


Infection Spread in Healthcare[edit | edit source]

Healthcare facilities, whether hospitals or primary care clinics are an area with an elevated risk of disease transmission due to the presence and relative ratio of susceptible individuals. One in ten patients get an infection whilst receiving care[10] yet effective infection prevention and control reduces healthcare-associated infections by at least 30%[10]. In a healthcare setting, the three components required for infection spread are the following[11]:

  • Source - places where infectious agents survive (e.g. sinks, hospital equipment, countertops, medical devices).
    • Environment - patient care areas, sinks, hospital equipment, countertops, medical devices.
    • People - patients, healthcare workers, or visitors.

  • Susceptible Person - Someone (Patient, Healthcare Worker, or Visitor) who is not vaccinated or immune to a particular infectious disease, or an individual with a compromised immune system / immunodeficient[11].
    • In addition, susceptibility can be heightened in individuals due to underlying medical conditions, medications, and necessary treatments and procedures that increase the risk of infection (for example, surgery).

  • Transmission - The way germs are moved to the susceptible person
    • Touch, including via medical equipment or a susceptible person (for example, MRSA or VRE)
    • Sprays or splashes (for example, Pertussis)
    • Inhalation of aerosolised particles (for example, TB or Measles)
    • Sharps injuries introducing blood-borne pathogens (for example, HIV, HBV, HCV)

Controlling Infectious Diseases Within Communities[edit | edit source]

Infection control and prevention is a global issue and there are many protocols and guidelines that can be followed to minimise the spread of infection between people, within a population and globally[2]. Identifying at-risk groups such as children, older people and those with chronic conditions can also help guide relevant strategies to protect these vulnerable groups. The first step when looking at infection control can start at the community level by changing behaviour, including:

  • Regular hand washing
  • Appropriate use of Face-masks (protect from and prevent spread of respiratory infections)
  • Using insect repellents
  • Ensuring up-to-date routine vaccinations and participating in immunisation programmes
  • Taking prescribed medications, such as antibiotics, as directed by health professionals
  • Social distancing - avoiding contact with others
  • Using condoms when having sex, especially with a new partner

Other steps that can be taken to control the spread within communities include environmental measures such as:

  • Modifying environments
  • Surveillance of diseases
  • Food safety
  • Air quality

Medical Interventions[edit | edit source]

As well as simple steps to prevent and control infections, there are biochemical interventions that can be implemented to speed up the recovery process and in some cases prevent viral infections completely.[12] The development of antibiotics, antivirals and vaccinations have been shown to speed up recovery, slow down the progression and in some cases eradicate infectious diseases from entire populations.

Antibiotics[edit | edit source]

Antibiotics are prescribed for bacterial infections and support the body's natural defence system to eliminate the disease-causing bacterial agent. They are designed to either kill bacteria or stop them from reproducing. However, poor use of antibiotics, over-prescribing and the mutation of bacteria has led the development of resistant bacteria[13]. In these cases, either stronger doses are required or the combination of one or more antibiotics.

Vaccinations[edit | edit source]

Vaccinations are designed to improve immunity to a particular disease. Vaccines work by introducing small amounts of the disease-causing virus or bacteria into the host, allowing them to build up natural immunity. The introduction of regular vaccines have slowed down and in some cases eradicated certain diseases such as polio, measles, mumps, whooping cough and rubeola (measles). There are also vaccinations for chickenpox, but this is not given routinely and is reserved for those at risk of spreading the disease to those with a weakened immune system[14]. This is due to the fact that it is prevalent in children under 10 years of age and symptoms are usually mild; this method allows them to build up natural immunity and contributes to improving the immunisation of a community[15]. This type of protection is known as herd immunity[16].

Antivirals[edit | edit source]

Antibiotics provide no defence for infectious diseases that are caused by viral agents such as influenza, HIV, herpes, and hepatitis B. In these cases, antiviral medications are the most effective at slowing down the progression of the disease and boosting the immune system. Unfortunately, as with antibiotics, viruses can mutate over time and become resistant to these antiviral drugs[13].

Infection Control in Healthcare Facilities[edit | edit source]


Another important factor in controlling and preventing infection is by improving practices in healthcare facilities. It is the duty of healthcare professionals worldwide to ensure they develop strategies and implement policies that protect those who may be immunocompromised in order to keep susceptible patients safe from healthcare-associated infections (HAIs). Globally, up to 7% of patients in developed and 10% in developing countries will acquire at least one HAI[2][17].

HAIs are one of the most common detrimental effects in care delivery and both the endemic burden and the occurrence of epidemics are a major public health concern. HAIs have a significant impact on morbidity, mortality[18] and quality of life and present an economic burden at the societal level. However, a large proportion of HAI are preventable and there is a growing body of evidence to help raise awareness of the global burden of harm caused by these infections, including strategies to reduce their spread[11].


Steps to Improve Infection Control[edit | edit source]

There are two tiers of recommended precautions by the Center of Disease Control and Prevention (CDC)[20] to prevent the spread of infections in healthcare settings: (1) Standard Precautions and (2) Transmission-Based Precautions[21][6].

Standard Precautions for All Patient Care:[edit | edit source]

  • Perform hand hygiene[22][23][24]
  • Use personal protective equipment (PPE) to prevent exposure to infection
  • Follow respiratory hygiene/cough etiquette principles
  • Ensure appropriate patient placement and isolation precautions[25]
  • Properly handle, clean, and disinfect patient care equipment and medical instruments
  • Handle and sterilise textiles and laundry carefully
  • Follow safe injection practices and proper handling of sharps/needles
  • Ensure healthcare worker safety via IPC and post-exposure prophylaxis
  • Prevention of intervention-related infections (catheter-associated urinary tract infections, intravascular catheter-related infections, surgical site infections)
  • The implementation of the specific isolation precaution when diagnosing some syndromes[25]
  • Improving the communication between health care workers especially when referring potentially contagious patients[26]
  • In paediatric departments or ambulatory settings, there should be efforts to decrease infection from contaminated toys. Families can be encouraged to bring their own toys[26]

Transmission-Based Precautions[edit | edit source]

Transmission-Based Precautions[27] used in addition to Standard Precautions for patients with infectious disease to prevent transmission:

  • Contact precautions
  • Droplet precautions
  • Airborne precautions


Further details and guidelines for transmission-based and isolation precautions are provided by the Centers for Disease Control and Prevention (CDC):

Infection Control Programmes in Acute Care[edit | edit source]

The CDC[29] suggest that the assessment and management of infection control programmes and practices in acute care hospital can be divided into 4 sections:

  • Section 1: Facility Demographics
  • Section 2: Infection Control Programme and Infrastructure
  • Section 3: Direct Observation of Facility Practices (optional)
  • Section 4: Infection Control Guidelines and Other Resources

They have produced a "Infection Prevention and Control Assessment Tool for Acute Care Hospitals" that is intended to assist in the assessment of infection control programmes and practices in acute care hospitals.

Environmental Cleaning and Disinfection[edit | edit source]

Evidence supports the important role of environmental cleaning in controlling the transmission of organisms (e.g.Staphylococcus Aureus, Vancomycin-resistant Enterococci, Norovirus, Clostridium Difficile and Acinetobacter), especially in hospitals and healthcare settings.[30]

If an individual with a suspected or confirmed case of infectious disease has attended your clinic, all surfaces that the person has come into contact with must be cleaned.

  • The room where they were placed/isolated should not be cleaned or used for one hour and the door to the room should remain shut.
  • The person assigned to clean the room should wear gloves (disposable single-use nitrile or household gloves) and a disposable apron (if one is available) then physically clean the environment and furniture using a household detergent solution followed by a disinfectant or combined household detergent and disinfectant, for example, one that contains a hypochlorite (bleach solution)[31]. Products with these specifications are available in different formats including wipes.
  • No special cleaning of walls or floors is required.
  • Pay special attention to frequently touched flat surfaces, backs of chairs, couches, door handles or any surfaces that the affected person has touched.
  • Discard waste (including used tissues, disposable cleaning cloths) into a healthcare risk waste bag (yellow).
  • Remove the disposable plastic apron (if worn) and gloves and discard into a healthcare risk waste bag.
  • If a healthcare risk waste bag is not available, place the waste in a small household waste bag and tie securely. Do not overfill. Then place the bag in a second household waste bag and tie securely. Store in a safe location. If the case is not confirmed the waste can be disposed of as per usual. If a case is confirmed public health will then advise you what to do with the waste.
  • Once this process has been completed and all surfaces are dry the room can be put back into use.

Infection Control Programmes Globally[edit | edit source]

The WHO Guidelines[2] on the Core Components of IPC Programmes at the national and facility level aim to enhance the capacity of countries to develop and implement effective technical and behaviour modifying interventions. They form a key part of WHO strategies to prevent current and future threats from infectious diseases such as Ebola, strengthen health service resilience, help combat antimicrobial resistance (AMR) and improve the overall quality of health care delivery. They are also intended to support countries in the development of their own national protocols for IPC and AMR action plans and to support health care facilities as they develop or strengthen their own approaches to IPC.


The "Executive Summary of the Minimum Requirements by Core Component" provides a good summary to present and promote the minimum requirements for IPC programmes at the national and health care facility level, identified by expert consensus according to available evidence and in the context of the WHO core components.

Infection Control in Disaster and Conflict Settings[edit | edit source]

The principles of IPC remain of paramount importance in emergency settings in order to protect yourself and your patients. This is especially important given the unsanitary conditions post-disaster and conflict in camps, which can create a perfect storm for infection, both for infectious diseases and wound infection. With a high incidence of complex, open traumatic injuries requiring surgery performed in sub-optimal surgical environments, there comes an increased risk of wound infection, which is further exacerbated by limited access to resources including clear (potable) water and medical consumables, creating significant challenges for rehabilitation professionals in many disaster and conflict settings.[33]

When working in an area where infectious diseases (e.g. cholera, diphtheria, Ebola, Middle East Respiratory Syndrome (MERS)) are an identified risk, additional IPC precautions will be in place. Make sure that you have had specific training and have been provided with additional PPE as required.[33]

Improving Social Determinants[edit | edit source]

Another important factor to consider in the control of infectious diseases is to address and improve social determinants of health within societies. There is a direct link between a person's health and their environment. WHO has identified three "common interventions" for improving health conditions worldwide[34]:

  • Education - There is a strong link between health and education[35].
  • Social Protection - Access to affordable healthcare and some form of social security system can also determine the health and behaviours in a community[36].
  • Urban Development - How our villages, towns and cities are designed can have a big impact on health and the spread of diseases. Living in overcrowded environments or in housing that is damp and/or that does not have adequate facilities and sanitation can increase the spread of infectious diseases[37].

Conclusion[edit | edit source]

There is no one solution to controlling the spread of infectious diseases, and effective IPC indeed requires government intervention and collaboration between healthcare agencies, individuals and communities. Until certain risk factors are addressed and behaviours modified, the war against infectious diseases will continue to be a predominant and costly health issue around the world.

Resources[edit | edit source]

The following resources expand further on the four sections mentioned above:

References[edit | edit source]

  1. Infection prevention and control [Internet]. World Health Organization. 2020 [cited 27 March 2020]. Available from:
  2. 2.0 2.1 2.2 2.3 2.4 World Health Organization. Guidelines on core components of infection prevention and control programmes at the national and acute health care facility level. World Health Organization; 2016.
  3. Tartari E, Tomczyk S, Pires D, Zayed B, Rehse AC, Kariyo P, Stempliuk V, Zingg W, Pittet D, Allegranzi B. Implementation of the infection prevention and control core components at the national level: a global situational analysis. Journal of Hospital Infection. 2021 Feb 1;108:94-103.
  4. Mayhall CG. Hospital epidemiology and infection control. Lippincott Williams & Wilkins; 2012 Feb 20.
  5. Control and Prevent the Spread of Germs [Internet]. Centers for Disease Control and Prevention. 2020 [cited 27 March 2020]. Available from:
  6. 6.0 6.1 Wilson J. Infection control in clinical practice. Elsevier Health Sciences; 2006 Jun 21.
  7. van Seventer JM, Hochberg NS. Principles of Infectious Diseases: Transmission, Diagnosis, Prevention, and Control. International Encyclopedia of Public Health. 2017:22.
  8. US Department of Health and Human Services. Principles of Epidemiology in Public Health Practice Third Edition An Introduction to Applied Epidemiology and Biostatistics. Chapter 8, Lesson 1. Atlanta, Georgia, USA Accessed 15 March 2020
  9. Let's Learn Public Health.Infectious Diseases - How do we control them? Published on 26 February 2017. Available from [last accessed 17 March 2020]
  10. 10.0 10.1 Infection prevention and control [Internet]. World Health Organization. 2020 [cited 27 March 2020]. Available from:
  11. 11.0 11.1 11.2 How Infections Spread | Infection Control | CDC [Internet]. 2020 [cited 15 March 2020]. Available from:
  12. Le Calvez H, Yu M, Fang F. Biochemical prevention and treatment of viral infections–A new paradigm in medicine for infectious diseases. Virology journal. 2004 Dec 1;1(1):12.
  13. 13.0 13.1 Drexler M, Institute of Medicine (US). What You Need to Know About Infectious Disease. Chapter 4. National Academies Press (US), Washington (DC); 2010.
  14. Chickenpox vaccine overview. NHS Website. Accessed 15 March 2020
  15. Brisson, M., & Edmunds, W. J. (2003). Economic Evaluation of Vaccination Programs: The Impact of Herd-Immunity. Medical Decision Making, 23(1), 76–82. doi:10.1177/0272989x02239651 
  16. Fine PE. Herd immunity: history, theory, practice. Epidemiologic reviews. 1993 Jan 1;15(2):265-302.
  17. Sydnor ER, Perl TM. Hospital epidemiology and infection control in acute-care settings. Clinical microbiology reviews. 2011 Jan 1;24(1):141-73.
  18. Borg MA. Cultural determinants of infection control behaviour: understanding drivers and implementing effective change. Journal of Hospital Infection. 2014 Mar 1;86(3):161-8.
  19. Lecturio Medical. COVID-19: Infectious Disease Precautions | Lecturio.Available from: [last accessed 29/12/2020]
  20. Dancer SJ. Control of transmission of infection in hospitals requires more than clean hands. Infection Control & Hospital Epidemiology. 2010 Sep;31(9):958-60.
  21. Infection Control Basics | Infection Control | CDC [Internet]. 2020 [cited 15 March 2020]. Available from:
  22. Pittet D. The Lowbury lecture: behaviour in infection control. Journal of hospital infection. 2004 Sep 1;58(1):1-3.
  23. Boyce JM, Pittet D. Guideline for hand hygiene in health-care settings: recommendations of the Healthcare Infection Control Practices Advisory Committee and the HICPAC/SHEA/APIC/IDSA Hand Hygiene Task Force. Infection Control & Hospital Epidemiology. 2002 Dec;23(S12):S3-40.
  24. Dancer SJ. Control of transmission of infection in hospitals requires more than clean hands. Infection Control & Hospital Epidemiology. 2010 Sep;31(9):958-60.
  25. 25.0 25.1 Rathore MH, Jackson MA, Committee on Infectious Diseases. Infection prevention and control in pediatric ambulatory settings. Pediatrics. 2017 Nov 1;140(5):e20172857.
  26. 26.0 26.1 McBride DL. Updated Guidelines on Infection Prevention in Pediatric Ambulatory Settings. Journal of pediatric nursing. 2018 Jan.
  27. Transmission-Based Precautions | Basics | Infection Control | CDC” [Internet]. 2020 [cited 15 March 2020]. Available from:
  28. Health portal Infection control, Available from: (last accessed 22.4.2019)
  29. Centers for Disease Control and Prvention. Infection Prevention and Control Assessment Tool for Acute Care Hospitals Accessed 17 March 2020
  30. Dancer SJ. The role of environmental cleaning in the control of hospital-acquired infection. Journal of hospital Infection. 2009 Dec 1;73(4):378-85.
  31. Wilcox MH, Fawley WN, Wigglesworth N, Parnell P, Verity P, Freeman J. Comparison of the effect of detergent versus hypochlorite cleaning on environmental contamination and incidence of Clostridium difficile infection. Journal of Hospital Infection. 2003 Jun 1;54(2):109-14.
  32. World Health Organization (WHO). WHO: What are the core components for effective infection prevention and control?. Available from: [last accessed 29/12/2020]
  33. 33.0 33.1 Lathia C, Skelton P and Clift Z. Early Rehabilitation in Conflicts and Disasters. Humanity and Inclusion. 2020
  34. World Health Organization (2013). The economics of social determinants of health and health inequalities: a resource book (PDF). World Health Organization. ISBN 978-92-4-154862-5
  35. Von dem Knesebeck O, Verde PE, Dragano N. Education and health in 22 European countries. Social science & medicine. 2006 Sep 1;63(5):1344-51.
  36. Chung H, Muntaner C. Welfare state matters: a typological multilevel analysis of wealthy countries. Health Policy, 2007, 80(2):328–339
  37. Thomson H, Atkinson R, Petticrew M, Kearns A. Do urban regeneration programmes improve public health and reduce health inequalities? A synthesis of the evidence from UK policy and practice (1980–2004). Journal of Epidemiology & Community Health. 2006 Feb 1;60(2):108-15.