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Etiology

Review: Infectious disease transmission in outpatient settings is associated with nonadherence to infection control procedures

ACP J Club. 1991 Sept-Oct;115:62. doi:10.7326/ACPJC-1991-115-2-062


Source Citation

Goodman RA, Solomon SL. Transmission of infectious diseases in outpatient health care settings. JAMA. 1991 May 8;265:2377-81.


Abstract

Objective

To review reports of outbreaks or clusters of infections resulting from transmission in outpatient health care settings and, based on this evidence, to develop potential infection-control and prevention strategies for these settings.

Data sources

Articles were identified from a MEDLINE search for the years 1966 to 1989, a hand search of relevant journals for the years 1980 to 1990, and a review of over 2900 epidemiologic field investigations in which the Centers for Disease Control and other agencies participated (1946 to 1989). Bibliographies of relevant articles were used to identify other relevant studies.

Study selection

Reports were included if they contained information that substantiated transmission of disease in outpatient settings other than hemodialysis and peritoneal dialysis facilities. 53 studies from 1961 to 1990 were included.

Data extraction

Epidemiologic and clinical data were extracted from each report.

Main results

23 reports studied transmission in office, clinic, or emergency department settings, and 13 reports documented episodes of common-source transmission, 10 of which resulted from contaminated disinfectants, antiseptic agents, medications, or vaccines. In 6 of these 13 reports, the etiologic agents were atypical mycobacteria. 9 instances of airborne or droplet transmission and 1 of person-to-person transmission occurred. Of the 11 reports in ophthalmologic settings, 9 were common-source and 2 were person-to-person transmission. 10 of the 11 outbreaks were of adenovirus keratoconjunctivitis associated with contaminated equipment and poor hand-washing practices. Dental settings were the sites in 13 reports, of which 11 were person-to-person, 1 was common-source, and 1 was airborne or droplet transmission. In 9 of the 11 person-to-person reports, the agent was hepatitis B virus; in 1, herpes simplex virus, and in 1, human immunodeficiency virus. The 6 outbreaks reported from alternative care settings (acupuncture, chiropractic, nutrition therapy, immunotherapy and weight-reduction clinics) were all caused by common-source transmission and included 3 outbreaks of hepatitis B transmission through contaminated equipment.

Conclusions

Most of the reported transmissions of infectious diseases in outpatient settings were associated with nonadherence to 1 of 3 infection control procedures: disinfection and sterilization of instruments and equipment; use of appropriate barrier precautions or restriction of infected health-care workers; good hand-washing procedures. Inpatient infection-control practices should be extended to outpatient settings.

Source of funding: Not stated.

Address for article reprint:Dr. R.A. Goodman, Epidemiology Program Office, Centers for Disease Control, Atlanta, GA 30333, USA.


Commentary

The potential for transmission of infectious diseases in the outpatient setting is an increasingly important concern as more (and more invasive) medical care is delivered outside of the hospital. This study begins the important task of developing a systematic approach to infection control for outpatient settings by providing a review of published reports of cases of infections acquired in outpatient settings. As the authors acknowledge, the conclusions that can be drawn are limited by biases that affect whether an infectious outbreak is reported, including, among others, the ease of documentation of specific organisms involved, the degree of interest in the circumstances or etiologic agent, and the number of persons involved. Further, information about the numbers and types of patients who did not develop the diseases being studied is not reported. Thus, this study does not permit conclusions regarding the frequency of outpatient transmission of infectious diseases, the specific infections that are most important, the types of patients and providers who are most at risk, or the most appropriate response to the problem.

The authors point out that infection control practices that are currently used in inpatient settings might have prevented many of the outbreaks they reviewed. The simplicity and sensibleness of hand washing, appropriate universal precautions, and disinfection of equipment between successive patients suggest that it is prudent for providers to incorporate these measures into their outpatient practices, despite the absence of reliable studies of efficacy. Prospective studies using epidemiologic and clinical research methods, however, are needed to establish the frequency and types of infections that are transmitted in outpatient settings, as well as the most appropriate strategies for their prevention and control.

Jeff Whittle, MD
Veterans Affairs Medical CenterPittsburgh, Pennsylvania, USA