Prevalence of Schistosomiasis-Tuberculosis Co-infection and Associated Factors Among Patients With Tuberculosis in the Lake Zone, Tanzania

Abstract

Background: Infectious diseases such as schistosomiasis and Tuberculosis (TB) are still a public health challenge in Sub Saharan Africa including Tanzania. In such co-endemic settings, schistosomiasis-TB co-infection is a common phenomenon. This population remains inadequately covered by current schistosomiasis control interventions, contributing to ongoing transmission. We investigated the current prevalence of schistosomiasis-TB co-infection and associated factors among patients with TB.
Methods: A baseline survey was conducted among patients with TB to assess the prevalence of schistosomiasis-TB co-infection and its associated factors in Mwanza region. A pre-tested questionnaire was used to collect both sociodemographic and clinical data. A single stool sample was collected from each participant and duplicate Kato Katz smears were prepared for the detection of intestinal schistosomiasis.
Results: A total of 540 patients with TB receiving treatment were enrolled in this study. The median age (IQR) of the studied population was 38 years (32, 45), with majority of the participants aged between 35 and 44 years (37.0%). Males accounted for the majority of participants (400/ 540, 74.1%). Out of the 540 patients screened, 159 (29.4%; 95% CI: 25.7- 33.0) were infected with intestinal schistosomiasis. Most participants had light intensity infections 136/540 (25.2%) while moderate intensity infection was observed in only 23/540 (4.3%). Notably, there was no heavy infection in the studied population. On multivariable regression analysis, being self-employed (aPR=1.98, 95% CI: 1.07-3.67; p=.03) or retired (aPR=2.72, 95% CI: 1.25-5.93; p=.01), presence of comorbidities (aPR=1.56, 95% CI: 1.12-2.05; p=.001), malaria infection (aPR=2.17, 95% CI: 1.56-3.03; p<.0001), abdominal pain (aPR=1.59, 95% CI: 1.20-2.11; p=.001), being anaemic (aPR=1.36, 95% CI: 1.05-1.76; p=.02) and having soft (aPR=1.69, 95% CI: 1.28-2.22; p<.0001) or loose stool (aPR=2.18, 95% CI: 1.37-3.46; p<.0001) were significant factors associated with TB schistosomiasis TB co-infection.
Conclusions: Our study highlights a significant burden of schistosomiasis TB co-infection among patients with TB. Comorbidities, malaria infection, anaemia and stool consistency were significantly associated with this co-infection. There is a need to consider including TB patients in mass drug administration campaigns while also addressing the associated factors through targeted interventions and integrated healthcare approaches to reduce morbidity and transmission among affected populations. Future research should continue to monitor the prevalence and intensity of co-infections and evaluate the effectiveness of praziquantel when co-administered with Rifampicin-based Anti-TB regimen.