In October 1980, 80% (120/150) of North Carolina (NC) hospitals responded to a comprehensive solid waste questionnaire intended to identify their solid waste disposal practices. NC hospitals generated an average of 13 lb. of solid waste/patient/day and infectious waste comprised 5% to 11% of the total hospital waste. Most hospitals (>66%) considered blood, isolation, laboratory (including microbiology), pathology, and autopsy waste as infectious, while other sources of solid waste were generally considered non-infectious. The infectious wastes were normally incinerated or steam sterilized before discarding. Nearly all hospitals (95%) used a Class A landfill to dispose of the non-infectious waste. Two-thirds of the NC hospitals are discarding blood, microbiological, pathological, and isolation waste in accordance with the CDC recommendations, while the compliance rates for the JCAH and EPA recommendations for these wastes were 94% and 24%, respectively. If the EPA modified its recommendations to include incineration of microbiological waste, which is practiced by 50 responding NC hospitals, the compliance rate would be 95.5% for these wastes and 61.7% overall.

A nursery outbreak of diarrheal illness caused by Salmonella nienstedten initially involved seven infants cared for in one nursery; secondary infection subsequently affected one infant cared for in the same nursery as well as four other infants. Recognition of the outbreak was delayed due to an unusually long incubation period. The period from last known exposure to onset of diarrhea ranged from two to 18 days, with a median of ten days. The prolonged incubation period may have resulted from a low inoculum of the organism, from a previously unknown characteristic of Salmonella nienstedten, or may be an age-specific response. Hospital infection control personnel should be aware that nosocomial cases of salmonellosis may have a longer incubation period than has been previously recognized.

This study evaluates the effect of a specially designed, physician-oriented handbook of antimicrobial use on the prescribing patterns of a group of 50 doctors at a university hospital. Data were evaluated over a period of one-and-one-half years, before and after the distribution of the handbook. For the purposes of this study, antimicrobial therapy was classified: 1) inappropriate if it violated one of a number of recognized principles of antimicrobial therapy, 2) appropriate if it agreed with specific recommendations or alternatives given in the distributed reference handbook, and 3) acceptable if it was neither inappropriate nor appropriate as defined by the handbook. An initial survey of antimicrobial prescribing patterns was made. Five months later the handbook was distributed. A two-week orientation program, consisting of the distribution and promotion of the problem-oriented, pocket-sized handbook of appropriate antimicrobial therapy, was conducted. The handbook, which was developed by the authors and reviewed and approved by a panel of infectious disease specialists, presented guidelines for appropriate and efficacious usage of antimicrobial agents as most currently accepted in common clinical infections. Subsequent surveys were then conducted two weeks, three months, and six months after distribution of the handbook. A statistically significant difference (p <0.01) in antimicrobial prescribing patterns was noted between the survey conducted two weeks after the introduction of the handbook and the other surveys. In this survey, while therapy classified inappropriate decreased from 45% to 28%, therapy considered appropriate as recommended increased from 33% to 53%. The findings of this study demonstrated that the introduction and promotion of the handbook decreased abuse and increased proper use of antimicrobial therapy, although the effect is sustainable for only a short duration—no longer than three months. These results indicate the need for a vigorous, updated program to achieve and maintain current appropriate antibiotic therapy in clinical medicine.

In a prospective study of 372 patients undergoing cardiac surgery, we evaluated the relative contribution of host factors and patient care variables to the risk of postoperative wound infection. Host factors studied were age, sex, country of origin, the diagnosis for which the operation was performed and, for coronary artery by-pass operations, the functional cardiac status according to modified New York Heart Association criteria. The performance of more than one operation during a single admission carried the highest risk for infection, followed by a coronary artery by-pass operation lasting for more than six hours or performed on patients 65 years or older. In patients undergoing coronary artery by-pass surgery, host factors (age and cardiac function) were associated with infections in the chest wound, while the length of the operation was found to affect the occurrence of infections at the “donor” site.

The efficacy of antibiotic resistance (barrier) precautions for control of aminoglycoside resistance was evaluated from 1978 to 1981. Despite increasing aminoglycoside use and a 13-fold increase in aminoglycoside-resistant isolates on a newly opened oncology unit, the hospital-wide frequency of aminoglycoside resistant Enterobacteriaceae remained low, supporting the continued value of barrier precautions which were initiated in our hospital in 1974. This control enabled us to focus on exceptions to the effectiveness of barrier precautions. These were traced to environmental reservoirs, very chronic and heavily infected patients, asymptomatic carriers of Serratia, and oncology patients receiving oral non-absorbable aminoglycosides. In addition, resistance in Pseudomonas aeruginosa paralleled aminoglycoside use and, as in our prior experience, continued to rise. With increasing adoption of barrier precautions by others such exceptions should be anticipated.

Found in the family Neisseriaceae, the genus Acinetobacter is large and contains many species formerly classified as Mima, Herellea, Moraxella, Bacterium, Achromobacter, and even Pseudomonas. Currently, only Acinetobacter calcoaceticus is recognized in Bergey's Manual. The phenotypic variability of this species, A. calcoaceticus, is explained on the basis of four biotypes. The biotypes are classed according to their hemolytic activity, production of gelatinase, ability to grow on Salmonella-Shigella (SS) agar, and production of acid from glucose. The two most clinically important and frequently encountered biotypes are A. calcoaceticus var. anitratus and A. calcoaceticus var. lwoffi. The other biotypes are A. calcoaceticus var. haemolyticus and A. calcoaceticus var. alcaligenes. Although they are not very virulent organisms, infections due to Acinetobacter species have been associated with a wide variety of nosocomial infections. Most infections involve patients with compromised host defenses. Acinetobacter has been associated with a variety of diseases including septicemia, with indwelling intravenous catheters as the suspected portal of entry; bacteriuria, usually associated with the presence of an indwelling bladder catheter; and pneumonias affecting those severely debilitated individuals who have undergone major surgery or trauma. Respiratory support equipment has been found to serve as a source or reservoir for these organisms. Most nosocomial colonizations and infections due to A. calcoaceticus are due to the anitratus variety.