Five of 18 samples of working dilutions of disinfectants used in the University of Ilorin Teaching Hospital, the University Clinic, and three other urban medical centers were found to be contaminated with bacteria. The results confirmed that disinfectants in storage support the growth of infectious agents, underlining the need to use fresh preparations of disinfectants.

The first paper in this series dealt with the similarities among the aminocyclitol agents. In the following discussion, we will emphasize the differences among the commercially available aminoglycosides, highlighting the pharmacokinetic and toxicologic data affecting their rational use.

I have two major concerns about the immunocompromised host field in 1989. The first relates to the tremendous impact that acquired immunodeficiency syndrome (AIDS) has had on nosocomial infections and the management of hospitalized patients. It is a major consideration in screening patients for organ transplants. Concern about AIDS influences all aspects of blood transfusion therapy.

The second concern relates to the increasing demand for expensive technologically-oriented procedures involved in the management of immunocompromised hosts. I believe the demand for these approaches is irresistible and adds to the mounting problems that hospitals face in containing basic costs. Since there is a finite dollar available for medical expenses, 1 see these demands exacerbating the rationing of medical resources.

Two questions confront data analysts: What's going on in the data? And how certain are the conclusions? One must deal with both questions to make rational decisions. John Tukey has called the two aspects of analysis exploratory and confirmatory. Consider, for example, a study in which patient data are analyzed for patterns that might identify causative agents for a particular disease. First, one should explore the data to reveal meaningful regularity (or perhaps irregularity might be a better way of saying it). For example, is there clustering in the geographic distribution of the patients that might indicate an environmental agent? After tentative pattern identification, confirmation is required to determine whether the patterns could simply be due to chance variation. That is, is the clustering strong enough to merit further detailed investigation or will the pattern disappear when further data are analyzed?

Classical statistical methods approach these questions through the foundation of probabilistic inference. I believe that it is no exaggeration to say that development of such methods during the 20th century are among the most important achievements in the history of science. They have contributed to the scientific method a systematic way of discerning what A.S.C. Ehrenberg calls “lawlike relationships” in empirical data. Their application has been decisive to progress in fields as diverse as nuclear physics, engineering design, genetics, agriculture, and paleontology, as well as medical science.

Coagulase-negative staphylococci (CONS) have only recently gained notoriety as pathogens. Several reports have established their pathogenicity in bacterial endocarditis, prosthetic heart valve endocarditis, intraventricular shunts for treatment of hydrocephalus and intravenous catheters. One difficult decision for physicians is determining whether a particular CONS isolate is pathogenic or contaminant. The differentiation of pathogenic and contaminant CONS has recently been noted, but further studies are needed to aid in this differentiation. Data on antimicrobial susceptibilities of positive blood culture isolates were recently compiled at this institution. This report compares antimicrobial susceptibilities of pathogenic and contaminant CONS and Staphylococcus aureus blood culture isolates from 1961-1981 at this institution.

We investigated whether the presence of hepatitis C virus (HCV) infection can be detected in hemostatic gauze used during oral treatments. We were able to detect both antibody to HCV and HCV RNA in samples from patients serologically proven to have HCV and also in gauze used for these patients that was left at room temperature even for as long as 24 hours. Thus, this method is useful for the screening of HCV infection in situations in which blood sampling is not feasible.

Intravenous (IV) therapy as a nursing specialty is based on principles of anatomy, physiology, pathophysiology, pharmacology, and infection control. Since IV therapy is an invasive procedure, it is germane that nurses strictly adhere to the fundamental principles that govern this area to assure patient protection. The focus of this article is to assimilate clinical expertise into a process for selecting IV tubing systems that are suitable for the delivery of the prescribed IV therapy.

The first principle that governs the selection of IV tubings is to choose a system that will deliver the prescribed therapy and minimize the risk of infection. The National Intravenous Therapy Association (NITA) Standards of Practice states that 0.22 μm filters shall be utilized for the delivery of IV therapy unless contraindicated. The 0.22 μm filters provide the following four safeguards to patients: 1) they remove particulate matter than could impede circulatory flow through the pulmonary vascular system. 2) They eliminate air from the system and consequently protect patients from the risk of air embolism. The design of the 0.22 μm filter allows air to be automatically vented from the system; therefore, no entry into the sterile IV system is required to remove the air. Because every entry into the IV system may result in inadvertent contamination, the air-eliminating capabilities of the 0.22 μm filter may also be classified as an infection control measure. 3) They will retain virtually every pathogen bacterium or fungus that may have entered the system.

Candida species were once largely regarded merely as causes of aggravating, but rarely life-threatening mucocutaneous infections such as thrush, vulvovaginitis, and intertrigo. Now, however, Candida species have assumed the role of major nosocomial pathogens. This change has paralleled the advent of aggressive cancer chemotherapy, the widespread use of parenteral nutrition, and the practice of advanced surgical techniques including cardiovascular procedures.

Candida is a heterogeneous genus presently grouped with the Fungi Imperfecti (Deuteromycetes). There are over 80 species of Candida; only seven, however, have been recovered from humans: Candida albicans, Candida tropicalis, Candida pseudotropicalis, Candida guilliermondi, Candida krusei, Candida parapsilosis, and Candida stellatoidea. Approximately 90% the systemic Candida infections are due to C. albicans; most of the remaining infections are due to C. tropicalis. Candida species are normal commensals of humans. They are commonly found on the skin, in the gastrointestinal tract, sputum, the female genital tract, and urine from catheterized bladders. C. albicans is found only in human beings and in animal reservoirs. In other sites, such as hospital environments, Candida probably represents contamination by human excreta. Other Candida species may be cultured from soil and other environmental locations. Unlike Aspergillus species, Candida species are uncommon laboratory contaminants.

A 24-question survey on varicella-zoster screening programs and control measures for varicella-zoster infections was sent to 170 Canadian healthcare facilities. The results indicated that 60% of Canadian healthcare facilities have well-established preemployment varicella-zoster screening programs for healthcare workers. Overall, 30% of healthcare facilities impose work restrictions for susceptible healthcare workers, 49% use negative-pressure rooms for varicella-zoster management, and 28% have a policy to discharge susceptible exposed patients. Large variations exist among Canadian healthcare facilities in their varicella-zoster infection control policies.