Nosocomial Infection: Introduction, Source, Control and Prevention
- Nosocomial infections result from pathogens that develop within a hospital or other type of clinical care facility and are acquired by patients while they are in the hospital.
- Besides harming patients, nosocomial infections can affect nurses, physicians, aides, visitors, salespeople, delivery personnel, custodians, and anyone who has contact with the hospital.
- Most nosocomial infections come clinically apparent while patients are still hospitalized; however, disease onset can occur after patients have been discharged.
- Infections that are incubating when patients are admitted to a hospital are not nosocomial; they are community acquired. However, because such infections can serve as a ready source or reservoir of pathogens for other patients or personnel, they are also considered in the total epidemiology of nosocomial infections.
- The CDC estimates that about 10% of all hospital patients acquire some type of nosocomial infection.
- Approximately 40 million people are admitted to hospitals annually, about 2 to 4 million people may develop an infection they did not have upon entering the hospital.
- Nosocomial infections represent a significant proportion of all infectious diseases acquired by humans.
- Nosocomial diseases are usually caused by bacteria, most of which are noninvasive and part of the normal microbiota; viruses, protozoa, and fungi are rarely involved.
Source of Nosocomial infections
- The nosocomial pathogens that cause diseases are of two types endogenous or exogenous sources.
- Endogenous sources are the patient’s own microbiota.
- Exogenous sources are microbiota other than the patient’s.
- Endogenous pathogens are either brought into the hospital by the patient or are acquired when the patient becomes colonized after admission.
- In either case the pathogen colonizing the patient may subsequently cause a nosocomial disease (e.g., when the pathogen is transported to another part of the body or when the host’s resistance drops).
- If it cannot be determined that the specific pathogen responsible for a nosocomial disease is exogenous or endogenous, then the term autogenous is used.
- An autogenous infection is one that is caused by an agent derived from the microbiota of the patient, despite whether it became a part of the patient’s microbiota following his or her admission to the hospital.
- There are many potential exogenous sources in a hospital.
- Animate sources are the hospital staff, other patients, and visitors.
- Some examples of inanimate exogenous sources are food, computer keyboards, urinary catheters, intravenous and respiratory therapy equipment, and water systems (e.g., softeners, dialysis units, and hydrotherapy equipment).
Control,Prevention, and Surveillance
- In the United States nosocomial infections prolong hospital stays by 4 to 13 days, result in over 4.5 billion dollars a year in direct hospital charges, and lead to over 20,000 direct and 60,000 indirect deaths annually.
- The enormity of this problem has led most hospitals to allocate substantial resources to the development of methods and programs for the sursurveillance, prevention, and control of nosocomial infections.
- All personnel involved in the care of patients should be familiar with basic infection control measures such as isolation policies of the hospital; aseptic techniques; proper handling of equipment, supplies, food, and excreta; and surgical wound care and dressings.
- To protect patients, hospital personnel must practice proper aseptic technique and handwashing procedures, and must wear gloves when contacting mucous membranes and secretions.
- Patients should be monitored with respect to the frequency, distribution, symptomatology, and other characteristics common to nosocomial infections.
- A dynamic control and surveillance program can be invaluable in preventing many nosocomial infections, patient discomfort, extended stays, and further expense.
Reference and Sources
- Overview of bioreactor or fermenters
- Types of microscopes
- Microscopy: Overview, Principles and Its Types
- Chickenpox (Varicella) and Shingles (Herpes Zoster)
- Fungal Disease