Biofilms in Infection Prevention and Control

A Healthcare Handbook

Steven L. Percival, David Williams, Tracey Cooper, Jacqueline Randle, Steven L. Percival, David Williams, Tracey Cooper, Jacqueline Randle

• Editorial: Academic Press
• Año: 2014
• ISBN:
  9780123977519
• Categoría: Biological Sciences
• Categoría: Microbiology

Biofilms in Infection and Disease Control: A Healthcare Handbook outlines the scientific evidence and rationale for the prevention of infection, the role biofilms play in infection control, and the issues concerning their resistance to antimicrobials. This book provides practical guidance for healthcare and infection control professionals, as well as students, for preventing and controlling infection.

Biofilms are the most common mode of bacterial growth in nature. Highly resistant to antibiotics and antimicrobials, biofilms are the source of more than 65 percent of health care associated infections (HCAI), which, according to the WHO, affect 1.4 million people annually. Biofilms are involved in 80 percent of all microbial infections in the body, including those associated with medical devices such as catheters, endotracheal tubes, joint prostheses, and heart valves. Biofilms are also the principle causes of infections of the middle-ear, dental caries, gingivitis, prostatitis and cystic fibrosis. Importantly, biofilms also significantly delay wound healing and reduce antimicrobial efficiency in at-risk or infected skin wounds.

• Provides specific procedures for controlling and preventing infection
• Includes case studies of HCAI, and identifies appropriate treatments
• Presents national government standards for infection prevention and control
• Includes extensive references and links to websites for further information

Part 1

Fundamentals of Infection Control

Outline

Chapter One Introduction to Infection and Infection Prevention

Chapter Two Infection Prevention: Principles of Safe Practice in Healthcare

Chapter Three Hand Hygiene

Chapter Four Decontamination

Chapter Five Challenges to Healthcare Providers

Chapter Six Changing Practice

Chapter Seven Invasive Devices

Chapter Eight Wounds and Infection

Chapter One

Introduction to Infection and Infection Prevention

Tracey Cooper and Steven L. Percival

Globally, millions of people receive some form of healthcare every year in every country of the world. One unintended consequence of healthcare interventions can be the development of a healthcare-associated infection. This chapter introduces some important issues regarding healthcare workers, patients and healthcare infections. Such infections can be avoided, and healthcare workers in particular are critical in making this happen. By better understanding the factors responsible for infections, healthcare professionals can apply measures which will contribute to the safe care that patients expect and deserve.

Keywords

healthcare; infection; biofilms; infection control

Introduction

Globally millions of people receive some form of healthcare every year in every country of the world. This ranges from basic non-invasive care to highly complex and technically advanced interventions and treatments. One unintended consequence of healthcare interventions can be the development of healthcare-associated infections (HCAI).

For many years the term hospital-acquired infection (HAI) was used, denoting that an infection was acquired during a hospital admission. In recent years it has been recognised that relatively complex care is increasingly being delivered in the community, including the patient’s own home, as well as in acute care hospital settings. The definition of HCAI takes this fully into account and includes all infections that develop as a result of healthcare, no matter where the care is delivered.

Rates of infection are measured in many countries using a variety of methods. This measurement is described as infection surveillance. Infection rates are usually reported as either prevalence rates or incidence rates. Prevalence rates are identified from surveys which collect information on the number of infections present at a given point in time and include those newly identified as well as those that are resolving and being treated. Incidence rates are identified from surveys that collect information over a period of time and include all new cases of infection as they occur. Prevalence rates are therefore higher than incidence rates.

Understanding of the importance of infection prevention and HCAI has developed over the past few decades, and there has been a corresponding increase in the amount of political and media attention given to HCAI in the United Kingdom and globally. It is clear that not all HCAI are avoidable, but much work has been done clearly demonstrating that most countries can reduce avoidable HCAI significantly if clinical practice is improved.

In 2006 the World Health Organisation (WHO) launched a Global Patient Safety Challenge in which it identified five major challenges for all countries. Included in this was the reduction of avoidable infection, including HCAI, by the promotion of hand hygiene. In the United Kingdom focussed action has been led by the government, the Scottish Executive and the Welsh Assembly. In England and Wales, the National Patient Safety Agency launched the ‘cleanyourhands’ campaign in 2004, and in Scotland the ‘Germs. Wash Your Hands of Them’ campaign was launched in 2007. These campaigns demonstrate that the prevention of HCAI is recognised as a critical factor for safe healthcare. The media across the United Kingdom and the United States continue to publish stories of patient infection and avoidable morbidity and mortality, and the public increasingly expects that all healthcare workers will act to reduce infection risk.

To reduce the risk of infection and to minimise adverse effects from infection when it does occur, healthcare workers need to:

• Implement good practice.

• Utilise evidence-based practice.

• Detect infection promptly through diagnostic tests and patient observation.

• Initiate effective treatment, including correct prescribing of systemic and topical antimicrobial agents.

• Document actions and interventions correctly and clearly.

• Communicate effectively with colleagues, patients, relatives and caregivers.

• Review infections that occur and learn from them so that we can improve care for other patients.

The Impact of Infection

When we consider the international perspective in more detail, it is evident that infection risks change radically across the globe. In many developing countries communicable disease and blood-borne viruses, such as HIV, spread readily. This is the result of financial and resource constraints that cause a lack of vaccination programmes and an inability to implement basic control measures during healthcare interventions. In countries with the resources to implement effective control measures, vaccination programmes and more complex healthcare procedures, it is rare that these infections spread. Instead, other micro-organisms present risks to those who receive healthcare and necessitate the need to implement effective control measures.

Healthcare-associated infections not only contribute to an increase in morbidity and mortality rates in hospitalised patients, but they also are associated with a substantial increase in healthcare costs.¹ Research has been conducted to identify the burden and economic cost of HCAI. Studies have estimated that in 1996, in England alone, the cost of HCAI was approximately ₤1 billion annually.^2,3

In England and Wales there have been four national prevalence surveys of infections in hospitals. The most recent, in 2011, identified an infection prevalence rate in England of 6.4%.⁴ The most common infection types were respiratory tract, urinary tract, and surgical site. Prior to this latest national point prevalence survey, the National Audit Office estimated that 5000 patients died every year in England because of HCAI³; specifically, meticillin-resistant Staphylococcus aureus (MRSA) was responsible for many cases.^5–7 The Scottish National HAI Prevalence Survey⁸ found similar trends.

The World Health Organisation conducted a worldwide study and concluded that more than 1.4 million people are affected by HCAI. This study was carried out in 55 hospitals across 14 countries and indicated that the rates of HCAI have increased. Globally it is estimated that 5 to 10% of hospitalised patients suffer from HCAI⁹ and that HCAI is responsible for one of the five top causes of death in the United States.¹⁰

Although the England and Wales survey¹¹ and the 2011 point prevalence survey⁴ provide a useful picture of infections in hospitals, they take no account of HCAI occurring either after discharge or as a result of healthcare interventions delivered outside the acute care setting. It is therefore important to remember that the real rate of infection is likely to be higher than the rate identified in these national surveys.

In addition, the Centers for Disease Control and Prevention (CDC) has proposed that 65% of all hospital-associated infections are a result of the presence of micro-organisms growing in a biofilm. This is discussed in more detail in Part 2 of this book.

Key Points

• On any day in an ‘average’ ward of 30 patients, 3 patients are suffering from an healthcare-associated infection.

• These 3 patients will be suffering avoidable pain and anxiety; they require extra medication, extra interventions (e.g., wound dressings and extra care) from a rang...