Metronidazole was introduced to the market in 1959 as the only effective therapy for Trichomonas vaginalis. A nitroimidazole derivative, its success in the therapy of parasitic infections, including Entamoeba histolytica and Giardia lamblia, has been well documented. Metronidazole's activity against anaerobic bacteria was first described in 1962 by Shinn, and by Davies and associates in 1964. In both reports, metronidazole effectively treated patients with Vincent's angina (necrotizing ulcerative gingivitis). Metronidazole's excellent activity against anaerobes has been substantiated by numerous articles. It has the best bactericidal activity of all drugs active against anaerobic bacteria.

Disseminated aspergillosis in the compromised host is an important and intractable problem in Great Britain, having a general incidence, when post-mortem data are included, approaching that quoted for the United States. It emerges as a most important cause of death in units where prolonged granulocytopenia accompanies treatment.

Rhame has presented a persuasive account of the environmental origin of aspergillus infection and the possibility of its control by environmental measures. This is an important issue for those involved in the planning of new units, for the use of protective isolation is under criticism as failing to provide significant benefit, and even general provision of filtered air to the unit may be beyond the budget allowed. We have to consider the minimum necessary measures to reduce the risk. Providing HEPA-filtered air to the unit may not be sufficient in itself; British heart transplant patients have died of aspergillosis (A. fumigatus), in some cases initiated soon after surgery, despite nursing in rooms with filtered ventilation (Newsom SWB, personal communication); and respiratory ventilators have been suspected as one source within such a unit. We also have to consider other approaches to the problem. Is there an endogenous element in the production of aspergillosis? Is there any prospect of successful chemoprophylaxis?

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.

The advent of a non-cost reimbursement system has served as an impetus for the re-examination of the methods by which infectious processes are treated. This system prospectively sets payment rates for illnesses that require hospitalization. Diagnostic-Related Groups (DRGs) are the basis of this new system. DRGs attempt to link reimbursement to the broad category of clinical diagnosis by separating diagnoses into nearly 500 groups; each with a defined reimbursement rate. This rate does not substantially vary with regard to the length of hospital stay, the number of diagnostic tests performed or the cost of therapy employed.

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.

In the hospital, both HTLV-III and hepatitis B virus are most likely to spread via infected blood or contaminated blood products. A summary of the main factors affecting spread of these viruses and some observations made at the author's hospital in central London, will be discussed here.

AIDS was first recognized in Britain in 1981 and up to August 1985 there were 206 confirmed cases of AIDS with 114 deaths. The majority of patients with AIDS have been male homosexuals and less than 15% of the cases occurred outside of London. By August 1985 over 10,000 cases of AIDS had been reported in the US and it is clear by comparison that the current epidemic in Britain is in its early stages. Only a minority of London homosexuals have been infected. It is possible that an aggressive public health campaign could slow the course of the epidemic. Measures needed would include an increase in education, publicity, facilities for HTLV-III antibody tests, trained social workers and counseling on a massive scale. In the meantime the number of hospitalized patients with known HTLV-III infections has increased considerably during the last 2 years in certain hospitals in London (Figure 1). Approximately 33% of homosexuals attending sexually transmitted diseases (STD) clinics in London have serological evidence of HTLV-III infection. A few hospitals in central London have seen most of the patients with known HTLV-III or hepatitis B infections mainly because of the concentrations of homosexuals, drug addicts or other “risk groups” in the local catchment areas of these hospitals. A small number of hospitals in London and elsewhere in Britain have special hemophiliac centers and currently these centers have generally noted that more than 50% of their hemophiliac patients already have serological evidence of HTLV-III infection. Recent reports have documented the rate of increase of HTLV-III infections in British hemophiliac patients. During the last few years in London less than 10% of male homosexuals known to have HTLV-III infection and less than 1% of infected hemophiliac patients have developed AIDS.

Microbiologists traditionally have relied on biochemical and serologic tests to identify only group A, group B, and group D streptococci isolated from patients with serious infections. Until recently there has been little interest in the further classification of other streptococci isolated from clinical specimens.

In 1956, Guthof repeatedly isolated a particular streptococcus from dental abscesses and named the organism Streptococcus milleri in honor of the microbiologist, W.D. Miller. In 1976, Parker and Ball associated this microorganism with other pyogenic infections and later described the characteristics of 346 strains. The Streptococcus milleri group is now recognized as both virulent and invasive and some believe it is responsible for more suppurative infections than any other group of streptococci. Physicians need to consider the unique ability of these bacteria to form abscesses in a wide range of tissue. Microbiology laboratories, therefore, need to develop schemes to identify this important group of streptococci.