The purpose of hygienic hand disinfection is to render hands safe after contact with pathogens. Comparing effects of disinfection procedures on infection ratios is too difficult for routine purposes but the degerming efficacy may be determined in laboratory tests with volunteers. In the Vienna test model the efficacy of a specific procedure being tested is compared to that of a standard disinfection (rubbing into hands 3 ml of iso-propanol 60% v/v, 30 seconds, twice) tested in parallel with the same volunteers. This ensures standardization, thus comparability of results between laboratories, and provides the investigator with a yardstick for efficacy. The model includes artificial contamination, assessment of the release of test bacteria (E. Coli ATCC 11229) before and after disinfection by the finger tip method, and addition of neutralizers to sampling fluids. Alcohols in appropriate concentrations are highly effective (log reductions: >4.0) whereas procedures employing disinfectant detergents act like soap (log reductions: ≤ 3.2) and may cause dissemination of pathogens.

The role of pre-operative disinfection of the surgeon's hands and the skin of the operative site in the prevention of wound infection remains uncertain. The normal resident skin flora, consisting mainly of coagulase-negative staphylococci and aerobic and anaerobic diphtheroids, is an uncommon cause of infection except in prosthetic operations. Staphylococcus aureus is rarely a resident on normal skin other than the perineum, and is mostly present on the hands as a transient acquired from the nose. Nevertheless, it seems rational to kill or remove all transients on the hands of the surgeon and reduce residents to low levels.

Surgical skin disinfection is usually assessed by measuring the reduction in organisms on the hands immediately after disinfection, after repeated applications of the disinfectant and after wearing gloves for two to three hours. The hands are commonly sampled in a bowl or plastic bag containing Ringer's or a similar solution and relevant neutralizers, or by the use of glove washings. A standardized technique is necessary to provide a statistical comparison between agents. Antiseptic detergents, chlorhexidine or povidone iodine show immediate reductions in bacterial counts of 70% to 80%, increasing to 99% after repeated application. Hexachloraphene and triclosan detergents show a lower immediate reduction but a good residual effect. Seventy percent ethyl or 60% propyl alcohol, with or without an antiseptic, show an immediate reduction of over 95%, and in excess of 99% on repeated application. Residual levels of organisms tend to be lower after repeated alcohol treatment than following the use of antiseptic detergents. A two to three-minute application of the antiseptic to the hands, without a scrubbing brush, is commonly recommended in the UK, but possibly in routine surgery an application time of 30 seconds is sufficient, killing or removing transients and superficial residents.

The rationale of degerming procedures is the elimination of undesirable microorganisms from sites serving as potential starting points for the transmission of infections, eg, secretions, excretions, and vehicles. The significance of transmission of infection is well-established for some sites, such as the hands, but debatable for others such as surfaces. No general agreement exists on the efficacy of the different procedures used to prevent hospital infections. Since frequently multiple factors intervene and the final effect is due to the interaction of several preventative measures, it is very difficult to ascertain the efficacy of any given procedure. However, to prevent the formation of germ depots outside the organism is a classical postulate of hygiene not yet invalidated.

Rationale and testing of degerming procedures are closely linked. From tests one expects an answer, if and to what extent a degerming procedure fulfills the requirement fixed by the rationale.

It is essential to distinguish between the degerming agent as the active principle and the degerming procedure, which is comprised of additional factors in the application.

Nosocomial infections consume a significant amount of the total hospital budget. This article describes some practical aspects for cost reduction in hospital infection control. Within one year total savings of 91.000 DM* could be achieved by discontinuing unnecessary disinfection procedures. Within six years 2,27 million DM could be saved by discontinuing unnecessary infection control procedures or employing cheaper methods. Of the total antibiotic costs 25% can be reduced by certain measures.

The effect on sepsis of the use of prophylactic antibiotics and measures for reducing the level of airborne contamination in the operating room has been related to the costs of these measures and of dealing with a septic joint. While antibiotic prophylaxis is the most cost effective, the benefits that may be obtained from the introduction of cleaner air also appear to be worthwhile, even when considered solely in terms of hospital costs.

The overall objectives for implementing an infection control program are to make hospital personnel aware of nosocomial infections and to educate these persons in their role in decreasing the risk of these infections. The infection control practitioner (ICP) implements these objectives by performing surveillance to determine problem areas and by developing policies and procedures that prevent and control nosocomial infections. Appropriate qualities for an ICP include initiative, leadership, communication skills, commitment, and charisma. Expertise in patient care practices, aseptic principles, sterilization practices, education, research, epidemiology, microbiology, infectious diseases, and psychology are acquired skills.

Local, state, and national organizations, as well as universities, are responsible for ICP training. In the US the Centers for Disease Control have established a training program for the beginning ICP and the Association of Practitioners in Infection Control (APIC) has developed a study guide for developing infection control skills. The ultimate responsibility for education is an individual obligation, however. Certification of the ICP would insure a minimum level of knowledge, thereby standardizing and upgrading the practice of infection control.

Dr. Phillips introduced his discussion about resistant staphylococci with the statement that nosocomial Staphylococcus aureus infections have steadily declined in England over the past two decades. The peak of infections with multiply antibiotic-resistant S. aureus strains was in the early 1960s. Toward the end of the 1960s, penicillin-resistance decreased and methicillin-resistance increased. Generally, resistant strains were found less frequently in the 1970s. No major outbreaks of cross-infection were seen in the United Kingdom since 1977 although Staphylococcus aureus did emerge from time to time, for example, in the recent epidemic of toxic shock syndrome, previously known to clinicians as staphylococcal scarlatina. In contrast, Staphylococcus epidermidis is in ascendency. In the early 1960s this organism was occasionally seen in stitch abscesses but then it appeared with increasing frequency in urinary tract infections and infections associated with intravascular devices. Dr. Phillips summarized his presentation with the statement that Staphylococcus aureus has lost its will to spread and, probably, to become resistant. Despite extreme provocations by medical procedures, only sporadic episodes of emergence seem to occur. Staphylococcus epidermidis, on the other hand, never had the will to spread but is more able to develop resistance. This organism is an example of the classic opportunist who receives a lot of help (from plastics!). During the discussion, several questions about staphylococcal taxonomy and methods of antimicrobial susceptibility testing were raised. Reference was made to the situation of staphylococcal infections in other countries; for example, the cyclic appearance of methicillin-resistant Staphylococcus aureus in the US.

Disinfectants come into contact with humans in two principal ways. First, they have involuntary contact with the skin and mucous membranes and are inhaled during the course of normal work. Second, they are applied purposefully directly to the skin and mucous membranes. This applies also to other chemicals in the hospital (eg, detergents), with the long-term danger being much greater for hospital personnel than for the patients.

There is increasing concern in the medical community regarding the safe handling and storage of biological materials procured from patients with Creutzfeldt-Jakob disease (CJD). Neurosurgeons have refused to operate on CJD patients, pathologists have refused to do autopsies on CJD patients, and hospitals have discharged CJD patients without confirmation of their diagnoses. This attitude was exemplified in the case of a director of a pathology laboratory who was so concerned about the safety of his laboratory personnel that he proposed to incinerate his entire collection of CJD slides. This extreme example is typical of the hysteria common among medical colleagues regarding the safe handling of CJD biological materials.