ASEPSIS AND INFECTION CONTROL
Introduction: Preventing transmission of infectious organisms is concern to all health care professionals. Infectious disease is one of the most common reasons people contact healthcare providers. Preventable infectious disease is common resulting in great suffering and loss of lives. Economic cost of preventing and treating infection are great.
Eg: Multidrug resistant organisms (MDROs), such as Tuberculosis, Entercocci, staphylococcus aureus and certain bacteria (E coli, Klebsiella pneumoniae, Acinetibacter baumanni).
Eradicating these bacteria is becoming increasingly difficult.
Additional emerging infectious diseases that emphasize the need for precise infection control practices include viral hemorrhagic fevers ( Ebola , Marburg viruses, Lujovirus), human influenza A HI N I (swine flu), human influenza A H5Nl (avian flu), and sever acute respiratory syndrome (SARS).
Role of microorganisms in infection:
• Microorganisms that are capable of harming people are called pathogens.
• When pathogens enter and multiply with in body tissues they disrupt normal physiology and produce infection.
• The organisms or their toxins disrupt normal cell function or kill the cells entirely.
• Transport on an infection or the product of infection throughout the body by the blood is known as septicemia.
• When a patient is referred to a septic, it means that he/she is displaying the manifestation of a systemic inflammatory state caused by widespread microbial destruction of tissues.
• Infectious disease refers to the pathological events that result from the invasion and multiplication of microorganisms in a host.
• Toxins and enzymes produced by the microorganism cause tissue injury. This injury produces manifestations of infection: fever, rashes, malaise. Nausea and vomiting, diarrhea, purulent discharge from wounds, a hot tender area around the wounds or punctured sites, aches and pains or total body collapse.
• It is very important to each and every health care professional devote a major portion of their time, energy, and talent to developing and maintaining practices to control the spread of microorganisms.
• Aseptic techniques important aspects of infection control and they start and end with hand washing including process of cleaning disinfection and sterilization.
• The use of barriers to prevent the spread of microorganisms such as gloves, masks, hair coverings, gowns and patient isolation as part of aseptic practice.
Agents causing infection :
· Single celled, independently living microorganisms.
· Transmit through air, food, water, soil, vectors or sexual activities.
· Differ in size shape, growth, replication requirement and the method by which they harm to the host.
· The capacity to diminish the function of the organ and cause inflammation.
· Some are capable of producing metabolic toxins called exotoxin. Eg; diphtheria, botulism, tetanus.
· Living microorganism composed of particles of nucleic acid and protein that are often membrane bound.
· Reproduce within the cells and cause various disease.
· Viral infections are acute and controlled by the body defense and others spread throughout the body causes chronic infection/illness. Eg; HIV, Hepatities Fungi:
· Single celled organisms that include molds and yeasts.
· Candida albicans present as part of normal human flora on mucous membranes and skin and in the GI tract and vagina.
· Candida infections are now as opportunistic infections because they do not result in disease in individuals with properly functioning immune system. Because they are the element of normal flora.
· Multicellular organisms that live on other organisms without contributing anything to their hosts. Eg; Protozoa: thrive in water. Eg Malaria
· Helminth: worms that infect GI system eg; tape worms, hookworms, and trichinae (porkworm)
· Arthropod: mites, fleas, ticks. Cause skin and systemic disease.
· They are infectious agents composed primarily of proteins that cause an abnormal folding of proteins in brain and neural tissue leading to brain damage. Eg:
· Bovine spongiform encephalopathy(BSE) called as ‘mad cow disease
· Creutzfeldt Jakob disease
Enterobacteriaceae: Salmonella, Shigella
Mycobacterium tuberculosis; multidrug resistant Spreptococcus Pemoniae, Haemophilus influenza and Neissera gnorrhoeae.
Staphylococcus aureus, Clostridium Difficile, Candida.
Porta of exit:
• Means for the microorganism to leave the source.
• Sputum, emesis, stool, urine, blood, wound drainage or genital secretions all permits microorganisms to exit the source.
Contact is the most common means of transmission in health care facility. Contact may be direct or indirect.
Direct transmission: occurs when infectious agents are transferred from one person to another – for example, a patient’s blood entering a healthcare worker’s body through an unprotected cut in the skin.
Indirect transmission: occurs when a susceptible host is exposed to a contaminated object such as shared patient care devices.