Nosocomial infections refers to infections acquired during hospitalization, with symptoms usually occurring within forty-eight hours after admission.
The origin of nosocomial infections can be attributed to the following:
- Bacterial flora already present in the patient;
- Microorganisms from the environment through transmission from: carriers colonized at admission, admitted to wards without undergoing surveillance, isolation or eradication of the germ(s); patients who have developed the infection but who have not been isolated;contact with contaminated objects and surfaces; medical personnel, usually via their hands; invasive procedures such as the installation or maintenance of a device(1).
The current probability of infection in health-care facilities is relatively high, and the risk of death is not negligible.
Data from the National Institute of Health (NIH) indicates that 4 million such infections occur in America every year, causing around 37,000 deaths. According to a study carried out by the Global Patient Safety Challenge: Clean Care Is Safer Care, at any one time more than 1.4 million people in the world are suffering from nosocomial infections. In developed countries, there is an incidence of 5%–10% in the total number of inpatients.
Hospital infections are also a major economic challenge for public health-care systems due to the impact they have upon health-care costs(2).
For example, infection by MRSA (methicillin-resistant Staphylococcus aureus) prolongs the average hospital stay by four to fourteen days, producing an increase in variable costs from between $10,000 and $36,000 per patient(3).
The cost, associated mainly with the increase in the number of days of hospitalization, can vary from $4,000 (for a patient hospitalizedin the department of medicine) to $28,000 (for a patient in intensive care)(4). In fact, the highest frequency of