An Evaluation of Systematic Tuberculosis Screening at Private Facilities in Karachi, Pakistan

Abstract

BackgroundIn Pakistan, like many Asian countries, a large proportion of healthcare is provided through the private sector. We evaluated a systematic screening strategy to identify people with tuberculosis in private facilities in Karachi and assessed the approaches' ability to diagnose patients earlier in their disease progression.Methods and FindingsLay workers at 89 private clinics and a large hospital outpatient department screened all attendees for tuberculosis using a mobile phone-based questionnaire during one year. The number needed to screen to detect a case of tuberculosis was calculated. To evaluate early diagnosis, we tested for differences in cough duration and smear grading by screening facility. 529,447 people were screened, 1,010 smear-positive tuberculosis cases were detected and 942 (93.3%) started treatment, representing 58.7% of all smear-positive cases notified in the intervention area. The number needed to screen to detect a smear-positive case was 124 (prevalence 806/100,000) at the hospital and 763 (prevalence 131/100,000) at the clinics; however, ten times the number of individuals were screened in clinics. People with smear-positive TB detected at the hospital were less likely to report cough lasting 2–3 weeks (RR 0.66 95%CI [0.49–0.90]) and more likely to report cough duration >3 weeks (RR 1.10 95%CI [1.03–1.18]). Smear-positive cases at the clinics were less likely to have a +3 grade (RR 0.76 95%CI [0.63–0.92]) and more likely to have +1 smear grade (RR 1.24 95%CI [1.02–1.51]).ConclusionsTuberculosis screening at private facilities is acceptable and can yield large numbers of previously undiagnosed cases. Screening at general practitioner clinics may find cases earlier than at hospitals although more people must be screened to identify a case of tuberculosis. Limitations include lack of culture testing, therefore underestimating true TB prevalence. Using more sensitive and specific screening and diagnostic tests such as chest x-ray and Xpert MTB/RIF may improve results.

BUTIMBA: Intensifying the Hunt for Child TB in Swaziland through Household Contact Tracing

“…In the first year of program implementation, modeling adjusted for declining national TB notification rates estimated 32% additionality resulting from our contact tracing program. Our program’s additionality declined in subsequent years likely reflecting the identification of prevalent cases in addition to incident cases during initial program implementation [24]. Our findings highlight the importance of robust and long-term program evaluation to accurately assess impact of newly introduced contact tracing interventions.…”

“…Similarly, the yield of source case investigation originating from index cases under five years of age participating in our program was 2.5%. But, our relatively lower overall program yield of 1.6% likely reflects our intervention’s community based entry point associated with earlier case detection which is associated with a higher NNS [24], lower certainty of diagnosis among children, and realistic implementation of a large community based intervention. Nevertheless, our source case investigations identified 2,476 additional cases for every 100,000 contacts screened suggesting a potential role for source case investigation in TB high burden settings.…”

Data for action: collection and use of local data to end tuberculosis

“…These data can be inputted directly using mobile devices. Countries 62 and cities 63,64 are increasingly developing individual-based electronic data systems. Mobile technology can also be combined with innovative methods to maximize case finding by reimbursing TB control officers promptly or providing appropriate incentives for finding additional cases 62 .…”

Evaluation of a Mobile Health Approach to Tuberculosis Contact Tracing in Botswana

“…Although a small number of mHealth approaches to TB contact tracing have been reported in the literature, this was the first study to evaluate an mHealth approach by directly comparing the time required to complete TB contact tracing and the quality of data collected with this method to those of the paper form–based approach (Brink el et al, 2014; Creswell et al, 2014; Interactive Research & Development, 2012; Kayiwa et al, 2013; Khan et al, 2012; Vella, 2012). …”

“…In addition to being portable and easy to use, these technologies can eliminate or reduce the need for paper forms and address many of the limitations of the paper form–based approach to TB contact tracing (Labrique et al, 2013; Timimi, Falzon, Glaziou, Sismanidis, & Floyd, 2012). Few mobile health (mHealth) approaches to TB contact tracing have been developed and evaluated, however (Brinkel, Krämer, Krumkamp, May, & Fobil, 2014; Creswell et al, 2014; Interactive Research & Development, 2012; Kayiwa, Irani, Ahmed, Klungsøyr, & Khan, 2013; Khan et al, 2012; Vella, 2012). …”