1. Nosocomial Infections Epidemiology and key concepts D-r Mitova MU-Sofia

9. OROPHARYNX Streptococcus viridans group Streptococcus pyogenes Streptococcus pneumoniae Staphylococci Moraxella catarrhalis Neisseria spp Corynebacterium spp Haemophilus spp Anaerobes: Bacteroides Candida albicans SKIN Staphylococci Corynebacteria Propionibacteria Candida Malassezia furfur CONJUNCTIVA Staphylococci Corynebacteria o GENITOURINARY TRACT Staphylococci, Streptococci Enterococci Lactobacillus spp, Corynebacterium Neisseria spp, Anaerobes Candida albicans UPPER INTESTINE Streptococci Lactobacillus spp Candida spp NASOPHARYNX Staphylococci Streptococci Moraxella catarrhalis Neisseria spp Haemophilus spp LOWER INTESTINE Aerobic G- bacilli: E.coli, Klebs Enterobacter, Proteus, Serratia Providencia, Bacteroides, Anaerobic Enterococci, Streptococci, Candida Flora at Colonization Sites

11. " An example of the most simple chain of infection is an infected patient cared for by a healthcare worker (HCW) who doesn't wash his or her hands before caring for another patient," says Richard Wenzel, MD, MSc, of the Department of Internal Medicine of Virginia Commonwealth University in Richmond, Va. Wenzel adds that contaminated hands are one of the most likely means of transmission of bacteria in hospitals.

12. Human sources of microorganisms are healthcare workers (HCWs), patients and visitors, any of whom may be individuals in the incubation period of a disease, those who already have a disease, or those who are considered to be chronic carriers of an infectious agent. Other sources of bacteria are the patient's endogenous (produced or originating from a cell or organism) flora and inanimate objects that have become contaminated

13. While there are five main routes of transmission of bacteria -- contact, droplet, airborne, common vehicle and vectorborne -- the first three routes are most critical to the discussion of nosocomial infections.

14. Infection control experts agree that following standard precautions, isolation guidelines when required and engaging in proper handwashing is essential to breaking the chain of infection. Following aseptic technique is especially critical when caring for patients with hardy microorganisms such as MRSA. A HCW can break the chain in the following way: Infectious agent : MRSA Reservoir : patient with MRSA in an open wound Portal of exit : drainage from the open wound; Break in the chain: HCW uses proper handwashing techniques, wears protective gloves and handles bed linens properly Mode of transmission : MRSA transferred on to hands by indirect contact; Break in the chain: HCW performs proper handwashing, gloving and linen handling Portal of entry : Break in the chain: Organisms isolated with use of medical asepsis and body-substance isolation Susceptible host : protected due to chain of infection being broken.