Inter- and intrahospital epidemics of nosocomial infections due to gram-negative bacilli resistant to many antimicrobials have been well-documented. Prospective studies on the use of isolation along with epidemiologic analysis and appropriate environmental control have been lacking. In the six-month period from November 1978 to April 1979 Pseudomonas aeruginosa (MDR) resistant to all antibiotics except amikacin was isolated from 15 patients. This organism had not previously been seen in our hospital. Epidemiologic assessment of infected patients revealed that nine of 15 patients had contact either with a previously infected case or contaminated area. All strains of P. aeruginosa were identical by pyocin typing and antibiogram. The organism was present in an environmental reservoir, the urine graduated cylinder, and was found in three of eight receptacles (p = 0.002 vs. other environmental cultures). A case control study of patient risk factors showed aminoglycoside use, other antibiotic use, surgery, intravenous lines, Foley catheter use and mechanical ventilation to be no more frequent in cases than controls. The use of aminoglycosides in only 40% of cases suggests that antibiotic pressure was not the sole factor in perpetuating the epidemic.

Q fever (Query Fever) is a zoonosis caused by the rickettsia Coxiella burnetii. Domestic ungulates such as sheep, cattle, and goats serve as the reservoir of infection for humans and shed the desiccation-resistant organism in urine, feces, milk, and especially in birth products. In humans the illness is generally mild; however, Q fever hepatitis is often seen and Q fever endocarditis is an uncommon, but frequently fatal complication. Q fever long has been recognized as an occupational hazard among persons working with animals or animal products, and in laboratories working with C. burnetii. Recently, Q fever outbreaks have occurred in medical research facilities using sheep as research animals. Recommendations are presented for reducing the risk of exposure to Q fever in persons not working with sheep in research facilities that use sheep. In addition, recommendations are presented for reducing the risk of infection in persons who work with sheep in research facilities.

We evaluated the efficacy of a daily bacteriologic monitoring program for preventing symptomatic urinary tract infections (UTI) in hospitalized patients with temporary indwelling urethral catheters. We identified 99 instances in which bacteriuria was present at the time of catheter insertion among 1,140 catheterizations. Of those, 62 patients were asymptomatic and 37 patients had fever or symptoms attributable to UTI. Of the 37 symptomatic episodes, only 14 developed symptoms 24 hours or more after the first culture and might be considered potentially preventable.

We also identified 76 episodes of acquired bacteriuria among 608 catheterizations that were initially non-bacteriuric in which at least two cultures were available. Of these 76 patients, 51 (67%) remained asymptomatic throughout their period of hospitalization. Of the 25 patients who developed symptomatic infections, only ten were potentially preventable.

In all, only 24 symptomatic episodes among 1,140 catheterizations (2%) occurred 24 hours or more after colonization was first detected and might be considered potentially preventable. Our data suggest that routine daily bacteriologic monitoring of urine from all catheterized patients is not an efficient way to decrease the incidence of symptomatic, catheter-associated UTI.

The exogenous contamination of a thermally injured patient by contact with the health care team has been a major concern of all burn units. Since the University of Chicago Burn Center routinely monitors each burn injury for sepsis by quantitative bacteriology and recently examined the microbial population present on the hands of the health care team, it was felt that these combined data would shed some pertinent information on exogenous burn wound sepsis.

Twenty-nine patients with clinical burn wound sepsis and a bacterial level of >105 bacteria/gram of tissue were studied. These patients yielded a variety of microorganisms with P. aeruginosa and Staphylococcus aureus being predominant, followed in incidence by Candida albicans. The resident and transient microflora isolated from each member of the health care team treating the specific individual concerned did not correlate with the causative agent of burn wound sepsis. The most frequent isolate from the staff personnel was Staphylococcus epidermidis followed by Micrococcus species.

Though colonization of the thermally injured individual has been reported, these data strongly suggest that colonization is primarily one of an endogenous source rather than that of an exogenous one.

A series of five successive cases of ultraviolet-induced erythroderma and keratoconjunctivitis, occurring over a one-month period and related to exposure to an improperly installed ultraviolet light are described. Although in this series, as well as others reviewed, the effects appeared self-limited, significant associated morbidity was observed.