Emerging epidemic of drug resistant tuberculosis in vulnerable populations of developing countries.

Dear Editor! Mycobacterium tuberculosis remains one of the greatest public health problems in developing countries. However evidence about spread, geographic occurrence and evolutionary genetics of Mycobacterium tuberculosis strains is scarce1. The foremost dilemma of many World’s TB Control Programs is the development of multidrug resistant tuberculosis (MDR TB). Although MDR TB cases are continuously being reported both in industrialized and unindustrialized countries, it is more widespread in developing countries with abject values of living2. Several socio-economic and biological aspects including poor chemotherapy, poverty, absence of vigilance and smoking are accountable for the TB prevalence. World Health Organization (WHO) has confirmed TB epidemic as a global emergency due to the associated reasons3. Several studies and analyses on susceptible groups have demonstrated that tuberculosis is more transferrable when Mycobacterium tuberculosis is present in sputum before any active anti-tuberculous treatment4. Youngsters are found to be at a larger risk of falling ill with active tuberculosis due to poor immunity while pediatric drug resistant TB undoubtedly specifies the transmission of drug resistant bacilli from grown-ups5.

developing countries with abject values of living 2 .Several socio-economic and biological aspects including poor chemotherapy, poverty, absence of vigilance and smoking are accountable for the TB prevalence.World Health Organization (WHO) has confirmed TB epidemic as a global emergency due to the associated reasons 3 .Several studies and analyses on susceptible groups have demonstrated that tuberculosis is more transferrable when Mycobacterium tuberculosis is present in sputum before any active anti-tuberculous treatment 4 .Youngsters are found to be at a larger risk of falling ill with active tuberculosis due to poor immunity while pediatric drug resistant TB undoubtedly specifies the transmission of drug resistant bacilli from grown-ups 5 .
World Health Organization has categorized 22 developing countries as high burden TB countries due to high incidence and prevalence rates of TB in these countries.WHO also categorized 27 countries as high burden MDR-TB countries.Among these 27 countries, 24 are developing countries whereas 3 are developed countries (Table : 1).worldwide.RFLP patterns help in epidemiological studies and provide information about origin of outbreaks and cross-contamination 17 .In addition to RFLP typing of IS6110, spoligotyping (spacer oligonucleotide typing) is also used to distinguish strains depending on DNA polymorphism of the M. tuberculosis direct repeat (DR) chromosomal region 18 .
There is no data existing from developing countries on the incidence of TB/MDR-TB in domestic interactions of MDR-TB patients 1 .Domestic contacts of MDR-TB suggest more recurrent threat of developing active TB and MDR-TB but such studies are rare 19 .Homelessness is a miserable condition, incorporating several liabilities that strikingly intensify the risk of being diseased, having latent TB infection (LTBI) and developing active disease.Homeless people generally have 10 to 85 times greater occurrence of LTBI and active TB and they may become a source of TB epidemics 20 .These realities highlight the significance of a steadfast and multidisciplinary methodology to these patients.Nonetheless, there is a dearth of epidemiological studies aiming on TB treatment aftermaths in vagrant people; few studies have addressed the influence of vagrancy on treatment consequences, and the existing facts came from high-income countries 20 .But the homelessness is more common in low-income countries.Mostly people live in inadequate housing or overcrowded houses where multigenerational families are confined into small places 20 .
To get better outcomes of TB control programmes for vulnerable individuals is a challenging chore which necessitates the multidimensional interventions, comprising governmental and communal engagements.Here are numerous obstacles, from funding to hominoid care and adherence to TB treatment is firmly subjected to malady perception and stigmatization 21 .Furthermore, TB treatment is linked with high direct/indirect expenditures, so communal funding is necessary to attain compliance.Emphasis on DOT approach together with incentives at each visit and bonuses after completion will contribute towards positive outcome.The blend of DOT with community support not only helps in healthier consequences but also empowerment of vagrant patients.

Table 1 : General Incidence and Prevalence of TB and burden of MDR TB in developing countries (Modified from Global Tuberculosis Report, 2015 1,10 ). 22 High burden TB Countries Estimated Incidence rate per 100,000 Estimated Prevalence rate per 100,000 27 High MDR-TB countries Percentage of MDR TB among the notified TB cases (%)
16vity, specificity, and speed of these tests16.Among these improvements, International agreement has been reached to use RFLP study of IS6110 (repetitive DNA which is specific to MTB) for subtyping M. tuberculosis isolates to enable evaluation of patterns among different strains African Health Sciences Vol 17 Issue 2, June, 2017