Bringing state-of-the-art diagnostics to vulnerable populations: The use of a mobile screening unit in active case finding for tuberculosis in Palawan, the Philippines

Abstract

BackgroundGlobally, case detection of tuberculosis (TB) has stabilized in recent years. Active case finding (ACF) has regained an increased attention as a complementary strategy to fill the case detection gap. In the Philippines, the DetecTB project implemented an innovative ACF strategy that offered a one-stop diagnostic service with a mobile unit equipped with enhanced diagnostic tools including chest X-ray (CXR) and Xpert®MTB/RIF (Xpert). The project targeted the rural poor, the urban poor, prison inmates, indigenous population and high school students.MethodsThis is a retrospective review of TB screening data from 25,103 individuals. A descriptive analysis was carried out to compare screening and treatment outcomes across target populations. Univariate and multivariate analyses were performed to identify predictors of TB for each population. The composition of bacteriologically-confirmed cases by smear and symptom status was further investigated.ResultsThe highest yield with lowest number needed to screen (NNS) was found in prison (6.2%, NNS: 16), followed by indigenous population (2.9%, NNS: 34), the rural poor (2.2%, NNS: 45), the urban poor (2.1%, NNS: 48), and high school (0.2%, NNS: 495). The treatment success rate for all populations was high with 89.5% in rifampicin-susceptible patients and 83.3% in rifampicin-resistant patients. A relatively higher loss to follow-up rate was observed in indigenous population (7.5%) and the rural poor (6.4%). Only cough more than two weeks showed a significant association with TB diagnosis in all target populations (Adjusted Odds Ratio ranging from 1.71 to 6.73) while other symptoms and demographic factors varied in their strength of association. The urban poor had the highest proportion of smear-positive patients with cough more than two weeks (72.0%). The proportion of smear-negative (Xpert-positive) patients without cough more than two weeks was the highest in indigenous population (39.3%), followed by prison inmates (27.7%), and the rural poor (22.8%).ConclusionsThe innovative ACF strategy using mobile unit yielded a substantial number of TB patients and achieved successful treatment outcomes. TB screening in prison, indigenous population, and urban and rural poor communities was found to be effective. The combined use of CXR and Xpert largely contributed to increased case detection.

Tuberculosis Treatment Outcomes Among Prisoners and General Population in Zomba, Malawi

“…In this study, gender comparisons were not possible among prisoners and the general population because the prison registered male TB patients only in the whole study period. Similar studies globally have shown unevenly distributed high proportions of male prisoners than female prisoners( [20,24,25]). Globally, there has been no universally accepted explanation to this disparity and most criminology studies point to the socialized gender roles and different expectations of male and female behaviors [26].…”

“…Several strategies can be combined to yield successful efforts in the fight against TB in the prison setting. TB mass screenings can be used to increase TB case detection [25]. Since the TB treatment outcomes are worsened by HIV positive status [5,21,28] scaling up of the 3 phase integrated screening and treatment for HIV, TB and nutrition during entry, stay and exit of prison could increase access to HIV, TB and Nutritional screening and subsequent linkage to appropriate treatment services.…”

Tuberculosis Treatment Outcomes Among Prisoners And Non-prisoners In Zomba, Malawi

“…In this study, gender comparisons were not possible among prisoners and non-prisoners because the prison registered male TB patients only in the whole study period. Similar studies globally have shown unevenly distributed high proportions of male prisoners than female prisoners( [19,23,24]). Globally, there has been no universally accepted explanation to this disparity and most criminology studies point to the socialized gender roles and different expectations of male and female behaviours [25].…”

“…In contrast, Prison settings have shown sub-optimal TB treatment success rates than the recommended 90 % set by the End TB Strategy. In Brazil, a retrospective study from 2007 -2011 showed that prisoners accounted for 5.7% (24,585) of the national TB registered cases with a 50% cure rate, 8% default rate, 1% death rate , 8% transfer out rate and in 30% the 'treatment outcome' field was not completed [17]. In South Africa, a retrospective study of 202 prisoners diagnosed with TB from 2007 -2009 showed a 45 % cure rate, 1% relapse rate, 0.5 % treatment failure rate, 1.8 death rate and 51% transfer out rate [18], while in Nigeria, a retrospective study of 48 prisoners diagnosed with TB from 2004 to 2008 showed a 67% treatment completion rate, 29 % transfer out rate and 4.2 % death rate [19].…”

Factors associated with household contacts’ tuberculosis testing and evaluation

“…The goal of TB control should be to provide patient‐centered care (Frieden, 2018) and support outreach activities to bring TB screening to the community, such as through the use of a mobile screening unit (Morano, Zelenev, Walton, Bruce, & Altice, 2014; Morishita et al., 2017) and broader educational efforts on TB, especially in high‐risk populations. These strategies will promote awareness in the community about the importance of TB screening and LTBI treatment.…”