Studies of the risk factors for bacteriuria associated with the use of temporary indwelling urinary catheters have focused on gram-negative bacilli and enterococci, the predominant causes of nosocomial urinary tract infection. During a prospective study of 747 catheterized patients, bacteriuria with ≥1,000 bacteria/mL were found in 96 patients. Coagulase-negative staphylococci (CNS) accounted for 19% of the episodes of bacteriuria, and S. epidermidis was the most frequent species of CNS. Significant risk factors for bacteriuria were a positive meatal culture for CNS, non-surgical illness, and no antibiotic therapy during catheterization. In contrast to the results of this and earlier studies that females were at greater risk factor for catheter-associated bacteriuria with gram-negative bacilli and enterococci, this was not a risk factor for acquisition of CNS. Possibly this is due to the more similar prevalence of meatal colonization with CNS of males and females compared to the striking difference in prevalence of meatal colonization with gram-negative bacilli and/or enterococci of males and females.

Kidney lithotripsy patients frequently receive epidural anesthesia via indwelling epidural catheters. In our hospital, patients are immersed in a tub of warm, continuously-flowing tap water. The epidural catheter-entry site is covered by a transparent occlusive dressing. To determine the risk of microbial colonization of the epidural catheter during lithotripsy, we performed quantitative cultures of tub water and semiquantitative cultures of catheters in 63 lithotripsy procedures. Most of the tub water organisms were typical tap water and skin flora isolates. Total colony counts were generally low with no significant progression during the course of serial procedures. Forty-two epidural catheters were cultured; 34 (81%) were sterile, 8 (19%) were colonized with small numbers of flavobacteria or coagulase-negative staphylococci. Only four catheters had organisms present on catheter segments covered by the transparent occlusive dressing (in each case there was a single colony forming unit per semiquantitative plate) and these organisms were probable contaminants. We conclude that with our current lithotripsy procedures, the risk for the development of epidural catheter-associated infection seems to be low.

Four cases of purulent complications in the heart following acute myocardial infarction are described. Fever occurred during the first week after coronary occlusion. In one case thrombophlebitis at an infusion site was followed by purulent pericarditis. One patient had an infected mural thrombus with peripheral septic embolic, and two suffered from streptococcal endocarditis. The association between these infections and recent acute myocardial infarction could be related to tissue necrosis and local thrombosis, but the increasing risk of bacteremia following invasive monitoring procedures in these patients is a risk factor that should not be ignored.

The studies described here evaluate the efficacy of the chlorxylenol-containing surgical scrub formulations against the Chlorhexidine gluconate-containing formulations using the Glove Juice Test, as recommended by the FDA's panel to develop guidelines for the study of antiseptic agents. Similar reports from the literature evaluating the relative efficacies of the iodophor-containing and the hexachlorophene-containing formulations are cited. Results fail to detect any significant differences in the efficacy of these two preparations, each significantly reducing the bacterial flora on the hands as indicated by immediate post-wash colony counts, and each demonstrating the continuing ability to significantly reduce bacterial growth with continued regular use.

In recent years there have been great advances made in antiviral therapy. One of the most promising of the new agents to be introduced is acyclovir. This antiviral, which selectively inhibits the replication of particular DNA viruses, is being used clinically in the treatment and prevention of viral infections caused by several of the herpes viruses. Though not a cure, acyclovir can be effective for the management of symptoms associated with these infections. Since acyclovir acts only on replicating viral DNA, the drug has no effect on the latent virus which establishes itself in neural tissue. This makes eradication of the virus very difficult.

Handwashing is the single most important procedure for preventing nosocomial infections. Handwashing is defined as a vigorous, brief rubbing together of all surfaces of lathered hands, followed by rinsing under a stream of water. Although various products are available, handwashing can be classified simply by whether plain soap or detergents or antimicrobial-containing products are used. Handwashing with plain soaps or detergents (in bar, granule, leaflet, or liquid form) suspends microorganisms and allows them to be rinsed off; this process is often referred to as mechanical removal of microorganisms. In addition, handwashing with antimicrobial-containing products kills or inhibits the growth of microorganisms; this process is often referred to as chemical removal of microorganisms. Routine handwashing is discussed in this Guideline; the surgical hand scrub is discussed in the Guideline for Prevention of Surgical Wound Infections.

Cleaning, the physical removal of organic material or soil from objects, is usually done by using water with or without detergents. Generally, cleaning is designed to remove rather than to kill microorganisms. Sterilization, on the other hand, is the destruction of all forms of microbial life; it is carried out in the hospital with steam under pressure, liquid or gaseous chemicals, or dry heat. Disinfection, defined as the intermediate measures between physical cleaning and sterilization, is carried out with pasteurization or chemical germicides.

Before 1970, regularly scheduled culturing of the air and environmental surfaces such as floors, walls, and table tops was widely practiced in US hospitals. By 1970, CDC and the American Hospital Association were advocating that hospitals discontinue routine environmental culturing, since rates of nosocomial infection had not been related to levels of general microbial contamination of air or environmental surfaces, and meaningful standards for permissible levels of microbial contamination of environmental surfaces did not exist. Between 1970 and 1975, 25% of US hospitals reduced the extent of such routine environmental culturing, and this trend has continued.

In the last several years, there has also been a trend toward reducing routine microbiologic sampling for quality control purposes. In 1982, CDC recommended that the disinfection process for respiratory therapy equipment should not be monitored by routine microbiologic sampling. Moreover, the recommendation for microbiolgic sampling of infant formulas prepared in the hospital has been removed from this Guideline, since there is no epidemiologic evidence to show that such quality control testing influences the infection rate in hospitals.

There is no epidemiologic evidence to suggest that most hospital waste is any more infective than residential waste. Moreover, there is no epidemiologic evidence that hospital waste disposal practices have caused disease in the community. Therefore, identifying wastes for which special precautions are indicated is largely a matter of judgment about the relative risk of disease transmission. Aesthetic and emotional considerations may override the actual risk of disease transmission, particularly for pathology wastes.

Although microorganisms are a normal contaminant of walls, floors, and other surfaces, these environmental surfaces rarely are associated with transmission of infections to patients or personnel. Therefore, extraordinary attempts to disinfect or sterilize these environmental surfaces are rarely indicated. However, routine cleaning and removal of soil are recommended. Recommendations for cleaning in the rooms of patients on isolation precautions have been published.

Although soiled linen has been identified as a source of large numbers of pathogenic microorganisms, the risk of actual disease transmission appears negligible. Rather than rigid rules and regulations, hygienic and commonsense storage and processing of clean and soiled linen are recommended. Guidelines for laundry construction and operation for health care facilities have been published.