Turning off the spigot: reducing drug-resistant tuberculosis transmission in resource-limited settings

Abstract

Ongoing transmission and re-infection, primarily in congregate settings, is a key factor fueling the global multidrug-resistant/extensively drug-resistant tuberculosis (MDR/XDR-TB) epidemic, especially in association with the human immunodeficiency virus. Even as efforts to broadly implement conventional TB transmission control measures begin, current strategies may be incompletely effective under the overcrowded conditions extant in high-burden, resource-limited settings. Longstanding evidence suggesting that TB patients on effective therapy rapidly become non-infectious and that unsuspected, untreated TB cases account for the most transmission makes a strong case for the implementation of rapid point-of-care diagnostics coupled with fully supervised effective treatment. Among the most important decisions affecting transmission, the choice of an MDR-TB treatment model that includes community-based treatment may offer important advantages over hospital or clinic-based care, not only in cost and effectiveness, but also in transmission control. In the community, too, rapid identification of infectious cases, especially drug-resistant cases, followed by effective, fully supervised treatment, is critical to stopping transmission. Among the conventional interventions available, we present a simple triage and separation strategy, point out that separation is intimately linked to the design and engineering of clinical space and call attention to the pros and cons of natural ventilation, simple mechanical ventilation systems, germicidal ultraviolet air disinfection, fit-tested respirators on health care workers and short-term use of masks on patients before treatment is initiated.

Figure 1

A basic triage and separation strategy, Haiti. TB = tuberculosis; HIV = human immunodeficiency virus. All images in this article can be viewed online in color at http://www.ingentaconnect.com/content/iuatld/ijtld/2010/00000014/00000010/art00004

Figure 2

Typical hospital room with high ceilings and tall windows in Lima, Peru.

Figure 3

New general hospital, Haiti, with improved design for airborne infection control.

Figure 4

Lesotho, with simple mechanical ventilation system, maintained by a service contract, and separation and isolation capacity.

Figure 5

Design and drawings of a new multidrug-resistant tuberculosis clinic and waiting area, Indus Hospital, Karachi, Pakistan.

Figure 6

Upper room ultraviolet germicidal irradiation fixture.

Figure 7

Routine use of disposable and reusable respirators on rounds at the PIH MDR-TB (Partners in Health Multidrug-Resistant Tuberculosis) Hospital, Lesotho.