CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND OF THE STUDY
Antiseptic and disinfectants are chemical agents that inhibit or destroy microorganisms on living tissue (antiseptics) and inanimate surfaces and objects (disinfectants). These chemical agents are used extensively in hospitals and other health care settings for a variety of topical and hard surface applications. In particular, they are an essential part of infection control practices and aid in the prevention of nosocomial infections. This wide spread use of antiseptic and disinfectant products has prompted some speculation on the development of microbial resistance, in particular, whether antibiotic resistance is induced by antiseptics or disinfectants. A wide variety of active chemical agents (biocides) are found in these products, many of which have been used for hundreds of years for antisepsis and disinfection including; alcohols, phenols, iodine, and chlorine. Most of these active agents demonstrate a broad spectrum of antimicrobial activity and they are used to reduce microbes on the living tissue or surface of medical equipment and other inanimate objects.
The mechanism of resistance to antiseptic and disinfectant solutions includes cellular impermeability, biofilm formation, efflux and mutations at the target site or over expression of a target site. As a therapeutic significance a number of bacterial contaminants isolated from antiseptics and disinfectants have exhibited resistance to commonly used antimicrobial agents. It has also been reported that contaminated antiseptics and disinfectants exhibit decreased efficacy and effectiveness. The response of different types of microorganisms to antiseptics and disinfectants vary and result in micro-biostatic or microbiocidal effects. Multiple nosocomial out breaks have resulted from a lack of intrinsic antimicrobial activity of antiseptics, resistant pathogen, over dilution of the antiseptics, or the use of contaminated antiseptics. Bacterial contamination of disinfectant solutions is common with preparation by unskilled personnel, use of unsterilized containers and prolonged use with other contributing factors for the high levels of contamination (dilution of disinfectants with tape water, inadequate care of stock solution bottles and long storage of the diluted disinfectants in the wards). In adequate disinfection of medical devices or environmental surfaces may result from lack of intrinsic antimicrobial activity of the disinfectant, an incorrect choice of chemical disinfectant, a resistant pathogen, over dilution of the disinfectant, inadequate duration of disinfection, lack of contact between the disinfectant and the microbes, or the use of contaminated disinfectants. With the emergence of pathogens such as Methicillin Resistant Staphylococcus Aureus (MRSA), Vancomycin Resistant Entericocci (VRE) and gram negative bacteria, for example, Pseudomonas aeruginosa and acinetobacter species which are resistant to multiple antibiotics, there is an increased need for effective antisepsis and disinfection. As with antibiotic resistance, resistance to these germicides may be an intrinsic property or may arise either by chromosomal gene mutation or by the acquisition of genetic materials. As a result of this health care associated infections are important causes of morbidity and mortality all over the world. The center for disease control and prevention (CDC) has estimated that health care associated infection accounts for an estimated 1.7 million infections, 99,000 deaths and $ 4.5 billion in excess health care costs annually.
Despite best efforts to eliminate these infectious microorganisms, they continue to emerge and re-emerge which contribute to human illness and death especially as a result of hospital acquired infections. The successful eradication of these pathogens with antiseptic/disinfectant solutions has been complicated by the development of highly resistant strains. As a result of extensive use of antiseptic/disinfectant solutions, a significant proportion of the pathogens have not only developed resistance, but they also grow in the solution of these biocides. The activity of biocides against microorganisms is not always consistent due to several basic methodological problems as well as high intrinsic resistance due to differences in membrane structure. Persistent reports have shown that disinfectants designed for the control of infectious microorganisms are themselves subjected to microbial contamination. It has become increasingly obvious that infections acquired in hospitals lead to increase morbidity and mortality which has also added noticeable to economic burden.
As different researchers show that contaminated antiseptics or disinfectants pose a health risk to patients particularly in the pediatric and surgical wards. Bacteria isolated from contaminated antiseptic/ disinfectant solutions exhibit increased resistance to commonly used antibiotics which contributes a serious public health problem, giving the fact that bacteria have the ability to share resistance markers, and once a resistance develops for one agent, a cross-resistance to other agents can occur. Nosocomial infections associated with contaminated antiseptic products are difficult to assess. Several factors may limit the identification of infections related to antiseptics or disinfectant products, however; it is a recognized public health problem worldwide with the prevalence rate of 5-10%. Generally these infections pose a problem of enormous magnitude globally by prolong hospitalization, increase cost of health care, and decrease the effectiveness of the treatment.
1.2 STATEMENT OF THE PROBLEM
One major cause of hospital infection is the use of contaminated disinfectants and antiseptics. Reports of epidemics of nosocomial bacterial infections have implicated contaminated disinfectants and antiseptics both applied directly to the skin of animals or humans and used to decontaminate instruments and appliances used for diagnosis and treatment. Hospitals are been using various disinfectants and antiseptics extensively, but there is no report on the microbial contamination of these biocides from any referral hospital from this part of the country.
1.3 OBJECTIVES OF THE STUDY
The aim of this study is to determine the microbial contamination of disinfectants and antiseptics produced and used in three major wards in Lagos University Teaching Hospital (LUTH) and to determine the microbial load in these wards.
1.4 RESEARCH QUESTIONS
1. What is the effect of microbial contamination of disinfectants and antiseptics produced and used in LUTH?
2. How can the level of microbial load of the contamination of disinfectants and antiseptics in three wards in LUTH be determined?
1.5 RESEARCH HYPOTHESES
Ho: There is no significant effect of microbial contamination of disinfectants and antiseptics produced in LUTH.
Hi: There is significant effect of microbial contamination of disinfectants and antiseptics produced in LUTH.
1.6 SIGNIFICANCE OF THE STUDY
This study is an attempt to improve the delivery of public health care in Lagos University Teaching Hospital, including reducing or eliminating contamination of disinfectants and antiseptics in pharmacy departments, pediatric/neonatal wards as well as of surgical equipment in surgical wards in LUTH. This study will be of immense benefit to other researchers who intend to know more on this topic and can also be used by non-researchers to build more on their work.
1.7 SCOPE/LIMITATIONS OF THE STUDY
This study was conducted to determine the prevalence of bacteria in disinfectants/antiseptics at three departments/wards in Lagos University Teaching Hospital (LUTH):
1. Pharmacy departments (pharmacy stock and diluted samples before delivery to wards).
2. Pediatric/neonatal wards (after delivery from the pharmacy department, diluted pre-use and in-use samples), and;
3. Surgical wards (after delivery from the pharmacy department, diluted pre-use and in-use samples). The investigation also determined the sensitivity of the bacteria to antimicrobial agents.
1.8 LIMITATIONS OF STUDY
This study will have some limitations most especially in the area of data collection. Financial constraints as well as time available for the completion of the study among other factors will limit the scope of the study.
1.9 BACKGROUND STUDY OF LAGOS UNIVERSITY TEACHING HOSPITAL (LUTH)
Lagos University Teaching Hospital (LUTH) is a tertiary referral hospital in Idi-Araba, Surulere, Lagos State, Nigeria. The hospital was established in 1962 and is affiliated with the University of Lagos, College of Medicine.
1.10 DEFINITION OF TERMS
ANTISEPTIC: An agent that inhibits or destroys microorganisms on living tissue including skin, oral cavities, and open wounds.
CHEMICAL DISINFECTANT: A chemical agent used on inanimate surfaces and objects to destroy infectious fungi, viruses, and bacteria, but not necessarily their spores. Sporicidal and antiviral agents may be considered a special class of disinfectants. Disinfectants are often categorized as high-level, intermediate-level, and low-level by medically oriented groups based upon their efficacy against various microorganisms.
CLEANING AGENT: An agent for the removal from facility and equipment surfaces of product residues that may inactivate sanitizing agents or harbor microorganisms.
DECONTAMINATION: The removal of microorganisms by disinfection or sterilization.
DISINFECTANT: A chemical or physical agent that destroys or removes vegetative forms of harmful microorganisms when applied to a surface.
SANITIZING AGENT: An agent for reducing, on inanimate surfaces, the number of all forms of microbial life including fungi, viruses, and bacteria.
SPORICIDAL AGENT: An agent that destroys bacterial and fungal spores when used in sufficient concentration for a specified contact time. It is expected to kill all vegetative microorganisms.
STERILANT: An agent that destroys all forms of microbial life including fungi, viruses, and all forms of bacteria and their spores. Sterilants are liquid or vapor-phase agents.
MICRO-ORGANISMS: Are microscopic organisms that exist as unicellular, multi-cellular, or cell clusters. Micro organisms are widespread in nature and are beneficial to life, but some can cause serious harm. They can be divided into six major types: bacteria, archaea, fungi, protozoa, algae, and viruses.
INFECTION: is the invasion of an organism’s body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to these organisms and the toxins they produce. Infectious disease, also known as transmissible disease or communicable disease, is illness resulting from an infection.
INFECTION CONTROL: Is the discipline concerned with preventing nosocomial or healthcare-associated infection, a practical (rather than academic) sub-discipline of epidemiology. It is an essential, though often under recognized and under supported, part of the infrastructure of health care.