Research on tuberculosis in tribal areas in India: A systematic review

Burden of Tuberculosis among tribal populations of India: A systematic review and meta-analysis

ABSTRACT

Tuberculosis (TB) continues to impose a significant burden on tribal populations in India, a high-risk group for the disease. Despite its preventable and curable nature, TB remains a formidable health challenge for these communities. However, a critical knowledge gap exists regarding the population-based prevalence of TB among tribal populations in India. The current systematic review and meta-analysis were carried out to provide a single, population-based estimate. A comprehensive search was conducted on PubMed, Embase, Scopus, and Web of Science databases using the keywords 'tuberculosis', 'TB', and 'tribal' or 'tribes'. This search encompassed articles published between 1 January 2000 and 1 March 2023. The included articles underwent a quality assessment screening to ensure their reliability and relevance. Subsequently, a pooled estimate of TB prevalence among tribal populations was quantified using a random-effects model. To investigate potential sources of heterogeneity in the prevalence estimates, subgroup analyses were performed. We identified 14 studies that encompassed a substantial population of 267,377 individuals from various regions in India belonging to tribal communities. The application of a random-effects model yielded a pooled prevalence estimate of 894.4 per 100,000 population, with a 95% confidence interval ranging from 523.5 to 1361.9. The assessment of heterogeneity using the Cochrane Q test indicated significant variability among the included studies (I2 = 99.17%; P < 0.001). Notably, the prevalence of TB among tribal populations was found to be higher than the national prevalence. The scientific evidence available for the prevalence of TB among tribal populations is restricted to a few tribes only. Conducting further research to estimate the prevalence among other tribes all over the country is the need of the hour and should be addressed accordingly.

Tuberculosis and the Effectiveness of the Revised National Tuberculosis Control Program (RNTCP) to Control Tuberculosis: A Narrative Review

The revised National Tuberculosis (TB) Control Program is an initiative undertaken by the government of India and was active from 1997 to 2020. Later it was renamed as National TB Elimination Program, which eyes the complete eradication of TB by 2025. The revised National Tuberculosis Control Programme (RNTCP) is preceded by the National TB Control Program which was activated when the cases of TB were on the rise in the early 1960s and police intervention was needed. National Tobacco Control Cell (NTCP) guided the efforts until 1997 when various shortcomings, which were registered over the course of time, were addressed and the revised program was launched. It has been a mixed success as beneficiaries belonging to the reachable, urban areas were benefitted, and tribal, and backward areas were lagging behind. Although the RNTCP proved to be effective in containing TB and curing it to a certain extent, the successor of the program, which is NTEP, has set an ambitious goal of eradicating TB by 2025 which needs concerted efforts on behalf of all stakeholders.

High incidence of pulmonary tuberculosis in an indigenous Saharia tribe in Madhya Pradesh, central India-A prospective cohort study

BACKGROUND

Lack of TB incidence data is an important evidence gap among Saharia-a high TB burden indigenous community in Madhya Pradesh, central India. The present study was undertaken to calculate the incidence of pulmonary tuberculosis in this tribe.

OBJECTIVE

To calculate the incidence of pulmonary tuberculosis (PTB) among the Saharia tribal population in Madhya Pradesh, central India.

METHODS

A prospective cohort study was conducted among the Saharia tribal population (aged 15 years and above) of Shivpuri district in Madhya Pradesh state in central India. A total of 9,756 individuals were screened for TB in the baseline TB prevalence survey during 2012-13. All available household members were screened for symptoms suggestive of pulmonary TB (presumptive TB). Two sputum specimens were collected from persons having symptoms suggestive of TB and examined by smear and culture tests. A cohort of all non-TB individuals in the baseline survey was followed-up for one year and re-screened for the sysmptoms of PTB in the year 2014-15. Based on the data collected, the incidence of TB over one year period was estimated per 100,000 population.

RESULTS

A total of 9756 and 9044 individuals (≥ 15 years) were screened for symptoms suggestive of PTB during baseline and endline surveys respectively. The sputum specimens of presumptive TB cases were collected and examined by smear and culture tests. The overall incidence of bacteriologically positive (smear and/or culture) PTB over one year period was 1504 (95% Confidence Interval (CI): 1273-1776) per 100,000 in the study population, the incidence of smear-positive PTB was 1106 (95% CI: 910-1343), and the incidence of culture-positive PTB was 1084 (95% CI: 890-1319) per 100,000 population. The incidence for both smear and culture-positive PTB was 686 (95% CI: 535-878) per 100,000 population in the year 2014-15. The incidence of PTB was 2.8 times higher in males compared to females (2259 vs 807 per 100,000) and was positively correlated with age.

CONCLUSION

The findings of the study, the first of its kind in the Saharia tribal population, indicate a high incidence of TB in this tribal community thereby highlighting the urgent need for focused and intensified efforts to achieve the goal of TB elimination in the country.

Persistent high prevalence of pulmonary tuberculosis in a resource-limited setting: threat to India's TB Free campaign

BACKGROUND

Tuberculosis (TB) is a major public health problem among Saharia, a particularly vulnerable tribal group residing in remote rural areas in central India. This article presents the findings from the baseline survey among Saharias and provides comprehensive prevalence data of pulmonary TB (PTB) in this marginalised community.

METHODS

A community-based cross-sectional PTB prevalence survey was carried out during January-May 2019 in selected villages using multistage stratified cluster sampling. All eligible adults (≥15 years of age) were screened for the symptoms of PTB. Sputum samples were collected and processed for microscopy and culture for Mycobacterium tuberculosis.

RESULTS

A total of 20 114 eligible individuals were screened for symptoms of PTB. Among these, 3001 (14.9%) individuals reported at least one PTB symptom and sputum was collected from 2890 (96.3%) individuals. Among these, 273 (9.4%) were bacteriologically positive for PTB. The overall prevalence was 1357 per 100 000 population.

CONCLUSIONS

The findings indicate that TB continues to be a major health problem in this marginalised community despite large investments by the government for TB control. This emphasizes the need to look into the causes and barriers in implementation of the TB elimination programme in the community, especially in view of India's TB elimination goal by 2025.

Spatiotemporal characteristics and the epidemiology of tuberculosis in China from 2004 to 2017 by the nationwide surveillance system

Background

China has always been one of the countries with the most serious Tuberculosis epidemic in the world. Our study was to observe the Spatial-temporal characteristics and the epidemiology of Tuberculosis in China from 2004 to 2017 with Joinpoint regression analysis, Seasonal Autoregressive integrated moving average (SARIMA) model, geographic cluster, and multivariate time series model.

Methods

The data of TB from January 2004 to December 2017 were obtained from the notifiable infectious disease reporting system supplied by the Chinese Center for Disease Control and Prevention. The incidence trend of TB was observed by the Joinpoint regression analysis. The Seasonal autoregressive integrated moving average (SARIMA) model was used to predict the monthly incidence. Geographic clusters was employed to analyze the spatial autocorrelation. The relative importance component of TB was detected by the multivariate time series model.

Results

We included 13,991,850 TB cases from January 2004 to December 2017, with a yearly average morbidity of 999,417 cases. The final selected model was the 0 Joinpoint model (P = 0.0001) with an annual average percent change (AAPC) of − 3.3 (95% CI: − 4.3 to − 2.2, P < 0.001). A seasonality was observed across the 14 years, and the seasonal peaks were in January and March every year. The best SARIMA model was (0, 1, 1) X (0, 1, 1)₁₂ which can be written as (1-B) (1-B¹²) X_t = (1–0.42349B) (1–0.43338B¹²) ε_t, with a minimum AIC (880.5) and SBC (886.4). The predicted value and the original incidence data of 2017 were well matched. The MSE, RMSE, MAE, and MAPE of the modelling performance were 201.76, 14.2, 8.4 and 0.06, respectively. The provinces with a high incidence were located in the northwest (Xinjiang, Tibet) and south (Guangxi, Guizhou, Hainan) of China. The hotspot of TB transmission was mainly located at southern region of China from 2004 to 2008, including Hainan, Guangxi, Guizhou, and Chongqing, which disappeared in the later years. The autoregressive component had a leading role in the incidence of TB which accounted for 81.5–84.5% of the patients on average. The endemic component was about twice as large in the western provinces as the average while the spatial-temporal component was less important there. Most of the high incidences (> 70 cases per 100,000) were influenced by the autoregressive component for the past 14 years.

Conclusion

In a word, China still has a high TB incidence. However, the incidence rate of TB was significantly decreasing from 2004 to 2017 in China. Seasonal peaks were in January and March every year. Obvious geographical clusters were observed in Tibet and Xinjiang Province. The relative importance component of TB driving transmission was distinguished from the multivariate time series model. For every provinces over the past 14 years, the autoregressive component played a leading role in the incidence of TB which need us to enhance the early protective implementation.

Prevalence, risk factors and health seeking behaviour of pulmonary tuberculosis in four tribal dominated districts of Odisha: Comparison with studies in other regions of India

AIM

To determine the prevalence of pulmonary tuberculosis, socio-cultural practices and health seeking behaviour of tribal people in four districts of Odisha.

METHODOLOGY

This was an action research study with qualitative and quantitative design following a sequential approach implemented in a 4-phased manner. It was carried out in the 6 selected villages from July,2015 to June,2017. The screening for active TB among chest symptomatics is followed as per the guidelines of the (RNTCP) Revised National Tuberculosis Control Program in India.

RESULTS

In all, 1455 households were surveyed in the 6 tribal dominated villages of 4 districts, namely Balangir, Dhenkanal, Kandhamal and Mayurbhanj. Total population of the villages was 6681. Based on the eligibility, 5144 (97.7%) individuals were screened. About 139 (2.3%) could not be screened due to non-availability in their households during day time. Out of the screened individuals (5144), 126 chest symptomatics were identified. Sputum samples were collected from them and sent to the National Reference Laboratory, RMRC, Bhubaneswar using public transport and maintaining cold chain. Out of 126 chest symptomatics, 35 patients were found to be having active TB disease and 18 were culture positive. The prevalence of pulmonary TB is 0.68%. The risk factors seemed to be ignorance about TB symptoms, addiction to alcoholic drinks, difficulty reaching the health facilities owing to the long distances, lack of communication and transport. In addition, other morbidities like Malaria, diabetes, hypertension, malnutrition, etc. were observed in the tribes of the study sites.

CONCLUSION

TB control programs need further strengthening in the tribal dominated regions. This study is the first of its kind in this State.

Out of pocket expenditure on tuberculosis in India: Do households face hardship financing?

BACKGROUND

In 2017, India accounted for 27 percent of the global burden on tuberculosis, and the highest among the top 30 countries with high TB burden. Despite the expansion of DOTS programme many households in India incur high expenditure towards TB treatment. Most of the studies in India have focused on measuring catastrophic health expenditure on TB. Catastrophic health expenditure and its impoverishment effects are difficult to calculate and may misrepresent economic hardship.

METHODS

This paper uses hardship financing, i.e. when a household sells assets or borrows money on interest to pay for healthcare expenditure, as an indicator of the hardship of the family when it spends on TB treatment using NSSO 71st Round 2014 data.

RESULTS

Using the NSSO national representative sample, the paper estimated that 26.7% of hospitalized cases and 3.5% percent of patients utilising outpatient care experience hardship financing due to TB in the country. 25.9% of the general population had to sell assets or used borrowings for financing TB hospitalization expenses. Education of head of household, income, type of health facility used, and number of hospitalized days were found to be significant factors influencing hardship financing.

CONCLUSION

Our study highlights that even with free care for tuberculosis, 21.3% were exposed to hardship financing, suggesting the need to re-look at the subsidy coverage of tuberculosis treatment in the country. The study also suggests the use of hardship financing as an alternative to catastrophic spending method as a index of effectiveness of tuberculosis control programme in the country.

Genotypic diversity of Mycobacterium tuberculosis isolates from North-Central Indian population

BACKGROUND

Different strains of Mycobacterium tuberculosis (MTB) are known to have different epidemiological and clinical characteristics. Some of them are widely distributed and associated with drug resistance, whereas others are locally predominated. Molecular epidemiological investigations have always been beneficial in identifying new strains and studying their transmission dynamics. Sahariya a primitive tribe of North Madhya Pradesh, India, has already been reported to have high prevalence of tuberculosis (TB) than their non-tribal neighbours. However, the information about MTB genotypes prevalent in Sahariya tribe and their non-tribal neighbours is not available.

METHODS

A total of 214 clinical isolates representing Sahariya tribe and non-tribes were analyzed by spoligotyping and MIRU-VNTR typing.

RESULTS

The EAI3_IND/SIT11 genotype was observed as major genotype in Sahariya tribe followed by CAS1_Delhi/SIT26 genotype. A 3.04 fold higher risk of getting TB with EAI3_IND/SIT11 genotype was observed in Sahariya as compared to the non-tribal population. The EAI_IND/SIT11 genotype also found to have more number of MDR-TB cases in Sahariya as well as true and possible transmission links. In Sahariya tribe, 3 clusters (6 isolates) reflected true transmission links, whereas 8 clusters consisted of 26 isolates revealed possible transmission links within the same geographical location or nearby houses.

CONCLUSION

The present study highlighted the predominance of EAI3_IND/SIT11 genotype in Sahariya tribe followed by CAS1_Delhi/SIT26 genotype. Combined approach of MIRU-VNTR typing and spoligotyping was observed more favourable in discrimination of MTB genotypes. Further, longitudinal studies using whole genome sequencing can provide more insights into genetic diversity, drug resistance and transmission dynamics of these prevalent genotypes.

Oral tuberculosis - Current concepts

Tuberculosis (TB) is a chronic infectious disease that can affect various parts of the body including the oral cavity. It primarily affects the lungs. TB bacilli can spread hematogenously to different parts of the body and this also involves maxilla or mandible. Although oral lesions are infrequent, they are crucial for the early diagnosis and interception of primary TB. Intercepting the disease early will limit the morbidity and mortality of the patients. It becomes the responsibility of the dentist to include TB in the differential diagnosis of suspicious oral lesions to prevent delay in the treatment of the disease. It would not be an exaggeration if the dental identification of the TB lesions has the potential of serving as a significant aid in the first line of control for this hazardous and often fatal disease. This article will also emphasize the advancing role of oral pathologists in making the final diagnosis of this dreaded disease.