Genotypic characterization of multi-drug-resistant Mycobacterium tuberculosis isolates in Myanmar.

The number of multi-drug-resistant tuberculosis (MDR-TB) cases is rising worldwide. As a countermeasure against this situation, the implementation of rapid molecular tests to identify MDR-TB would be effective. To develop such tests, information on the frequency and distribution of mutations associating with phenotypic drug resistance in Mycobacterium tuberculosis is required in each country. During 2010, the common mutations in the rpoB, katG and inhA of 178 phenotypically MDR M. tuberculosis isolates collected by the National Tuberculosis Control Program (NTP) in Myanmar were investigated by DNA sequencing. Mutations affecting the 81-bp rifampicin (RIF) resistance-determining region (RRDR) of the rpoB were identified in 127 of 178 isolates (71.3%). Two of the most frequently affected codons were 531 and 526, with percentages of 48.3% and 14.0% respectively. For isoniazid (INH) resistance, 114 of 178 MDR-TB isolates (64.0%) had mutations in the katG in which a mutation-conferring amino acid substitution at codon 315 from Ser to Thr was the most common. Mutations in the inhA regulatory region were also detected in 20 (11.2%) isolates, with the majority at position -15. Distinct mutation rate and pattern from surrounding countries might suggest that MDR-TB has developed and spread domestically in Myanmar.

Equity and the Sun Quality Health Private Provider Social Franchise: comparative analysis of patient survey data and a nationally representative TB prevalence survey.

INTRODUCTION: Since 2004, the Sun Quality Health (SQH) franchise network has provided TB care in Myanmar through a network of established private medical clinics. This study compares the wealth distribution of the TB patients to non-TB patients to determine if TB is most common among the poor, and compares the wealth of all TB patients to SQH TB patients to assess whether the franchise achieves its goal of serving the poor. METHODS: The study uses data from two sources: 1) Myanmar's first nationally representative TB prevalence study conducted in 2009, and 2) client exit interviews from TB patients from SQH clinics. In total, 1,114 TB-positive individuals were included in the study, including 739 from the national sample and 375 from the SQH sample. RESULTS: TB patients at SQH clinics were poorer than TB-positive individuals in the overall population, though not at a statistically significant level (p > 0.05). After stratification we found that in urban areas, TB patients at SQH clinics were more likely to be in the poorest quartile compared to general TB positive population (16.8% vs. 8.6%, respectively; p < 0.05). In rural areas, there was no statistically significant difference between the wealth distribution of SQH clinic patients and general TB positive individuals (p > 0.05). CONCLUSION: Franchised clinics in Myanmar are reaching poor populations of TB patients in urban areas; more efforts are needed in order to reach the most vulnerable in rural areas.

The fourth national tuberculosis prevalence survey in Myanmar.

Tuberculosis (TB) remains a significant cause of morbidity and mortality in Myanmar. The fourth National TB Prevalence Survey was conducted in 2017-2018 to determine the actual burden of TB not only at the national level but also for three subnational strata (the states, regions other than Yangon, and the Yangon region) and develop a more efficacious country strategy on TB care and control. One hundred and thirty eight clusters were selected by population proportionate sampling. Adult (≥15 years of age) residents having lived for 2 weeks or more in the households of the selected clusters were invited to participate in the survey. The survey participants were screened for TB by a questionnaire and digital chest X-ray (CXR) after providing written informed consent. Individuals with a positive symptom screen and/or chest X-ray suggestive of TB were asked to provide sputum samples to test for Mycobacterium tuberculosis (Mtb) by Ziehl-Neelsen direct light microscopy, Xpert MTB/RIF Ultra (Xpert), and culture (Ogawa media). Bacteriologically confirmed TB cases were defined by an expert panel. Of 75 676 eligible residents, 66 480 (88%) participated, and 10 082 (15%) screened positive for TB. Among these, 322 participants were defined as bacteriologically confirmed TB cases. Cough lasting for two weeks or longer, one of the criteria used for screening for symptoms, could detect only 14% (45/322) of the study cases. The estimated prevalence of bacteriologically confirmed adult pulmonary TB was 468 (95% CI: 391-546) per 100,000. The prevalence was much higher among males, the older age group, urban Yangon and remote villages. In-depth interview with the participants on TB treatment showed that none of them was diagnosed in a TB health centre (primary care facilities). The prevalence of TB in Myanmar is still high due to challenges such as uncontrolled urbanization, an ageing population, migration, and poor access to health facilities in remote areas. New screening and diagnostic tools might help to detect more TB patients. There is a need to lay greater emphasis on multisectoral approaches, decentralization and the integration of basic TB services into primary care facilities.

Prevalence and seroprevalence of Plasmodium infection in Myanmar reveals highly heterogeneous transmission and a large hidden reservoir of infection.

Malaria incidence in Myanmar has significantly reduced over recent years, however, completeness and timeliness of incidence data remain a challenge. The first ever nationwide malaria infection and seroprevalence survey was conducted in Myanmar in 2015 to better understand malaria epidemiology and highlight gaps in Annual Parasite Index (API) data. The survey was a cross-sectional two-stage stratified cluster-randomised household survey conducted from July-October 2015. Blood samples were collected from household members for ultra-sensitive PCR and serology testing for P. falciparum and P. vivax. Data was gathered on demography and a priori risk factors of participants. Data was analysed nationally and within each of four domains defined by API data. Prevalence and seroprevalence of malaria were 0.74% and 16.01% nationwide, respectively. Prevalent infection was primarily asymptomatic P. vivax, while P. falciparum was predominant in serology. There was large heterogeneity between villages and by domain. At the township level, API showed moderate correlation with P. falciparum seroprevalence. Risk factors for infection included socioeconomic status, domain, and household ownership of nets. Three K13 P. falciparum mutants were found in highly prevalent villages. There results highlight high heterogeneity of both P. falciparum and P. vivax transmission between villages, accentuated by a large hidden reservoir of asymptomatic P. vivax infection not captured by incidence data, and representing challenges for malaria elimination. Village-level surveillance and stratification to guide interventions to suit local context and targeting of transmission foci with evidence of drug resistance would aid elimination efforts.

Predominance of Mycobacterium tuberculosis EAI and Beijing lineages in Yangon, Myanmar.

Isolates of the Mycobacterium tuberculosis Beijing lineage are associated with high rates of transmission, hypervirulence and drug resistance. The Beijing lineage has been shown to dominate the tuberculosis (TB) epidemic in East Asia; however, the diversity and frequency of M. tuberculosis genotypes from Myanmar are unknown. We present the first comprehensive study describing the M. tuberculosis isolates circulating in Yangon, Myanmar. Thus, 310 isolates from pulmonary TB patients from Yangon, Myanmar, were genotyped by spoligotyping and IS6110-based restriction fragment length polymorphism analysis (IS6110 RFLP). The most frequent lineages observed were the East African-Indian (EAI; 48.4%; n = 150) and Beijing (31.9%; n = 99) lineages. Isolates belonging to the most frequent shared types (STs), ST1 (n = 98; Beijing), ST292 (n = 28; EAI), and ST89 (n = 11; EAI), had >or=75% similarity in their IS6110 patterns. Five of 11 Beijing isolates comprising five clusters with identical IS6110 RFLP patterns could be discriminated by mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis. Of the 150 EAI isolates, 40 isolates (26.7%) had only one IS6110 copy, and 17 of these isolates could be discriminated by MIRU-VNTR analysis. The findings from this study suggest that although there is a predominance of the ancient EAI lineage in Yangon, the TB epidemic in Yangon is driven by clonal expansion of the ST1 genotype. The Beijing lineage isolates (21.4%) were more likely (P = 0.009) than EAI lineage isolates to be multidrug resistant (MDR) (1.3%; odds ratio, 3.2, adjusted for the patients' history of exposure to anti-TB drugs), suggesting that the spread of MDR Beijing isolates is a major problem in Yangon.

Whole-genome sequencing of multidrug-resistant Mycobacterium tuberculosis isolates from Myanmar.

Drug-resistant tuberculosis (TB) is a major health threat in Myanmar. An initial study was conducted to explore the potential utility of whole-genome sequencing (WGS) for the diagnosis and management of drug-resistant TB in Myanmar. Fourteen multidrug-resistant Mycobacterium tuberculosis isolates were sequenced. Known resistance genes for a total of nine antibiotics commonly used in the treatment of drug-susceptible and multidrug-resistant TB (MDR-TB) in Myanmar were interrogated through WGS. All 14 isolates were MDR-TB, consistent with the results of phenotypic drug susceptibility testing (DST), and the Beijing lineage predominated. Based on the results of WGS, 9 of the 14 isolates were potentially resistant to at least one of the drugs used in the standard MDR-TB regimen but for which phenotypic DST is not conducted in Myanmar. This study highlights a need for the introduction of second-line DST as part of routine TB diagnosis in Myanmar as well as new classes of TB drugs to construct effective regimens.

Phenotypic and genotypic analysis of anti-tuberculosis drug resistance in Mycobacterium tuberculosis isolates in Myanmar.

BACKGROUND: Tuberculosis (TB) is one of the most serious health problems in Myanmar. Because TB drug resistance is associated with genetic mutation(s) relevant to responses to each drug, genotypic methods for detecting these mutations have been proposed to overcome the limitations of classic phenotypic drug susceptibility testing (DST). We explored the current estimates of drug-resistant TB and evaluated the usefulness of genotypic DST in Myanmar. METHODS: We determined the drug susceptibility of Mycobacterium tuberculosis isolated from sputum smear-positive patients with newly diagnosed pulmonary TB at two main TB centers in Myanmar during 2013 by using conventional phenotypic DST and the GenoType MTBDRplus assay (Hain Lifescience, Germany). Discrepant results were confirmed by sequencing the genes relevant to each type of resistance (rpoB for rifampicin; katG and inhA for isoniazid). RESULTS: Of 191 isolates, phenotypic DST showed that 27.7% (n=53) were resistant to at least one first-line drug and 20.9% (n=40) were resistant to two or more, including 18.3% (n=35) multidrug-resistant TB (MDR-TB) strains. Monoresistant strains accounted for 6.8% (n=13) of the samples. Genotypic assay of 189 isolates showed 17.5% (n=33) MDR-TB and 5.3% (n=10) isoniazid-monoresistant strains. Genotypic susceptibility results were 99.5% (n=188) concordant and agreed almost perfectly with phenotypic DST (kappa=0.99; 95% confidence interval 0.96-1.01). CONCLUSIONS: The results highlight the burden of TB drug resistance and prove the usefulness of the genotypic DST in Myanmar.

Hospital-based surveillance for rotavirus diarrhea in children in Yangon, Myanmar.

Diarrhea is a common childhood illness in Myanmar, and rotavirus is the single most important etiological agent of diarrhea. Surveillance for rotavirus diarrhea in children <5 years of age was conducted in a tertiary pediatric hospital in Yangon, Myanmar, from January 2002 through December 2003. Stool specimens obtained from children admitted to the hospital for acute diarrhea were tested for the presence of rotavirus by use of an enzyme-linked immunosorbent assay. Diarrhea was the cause of 5671 (18%) of all hospitalizations of children <5 years of age during the 2-year study period (n = 30,869). Rotavirus was identified in 923 (53%) of the 1736 stool specimens tested, and rotavirus infection was associated with approximately 10% of all hospitalizations of children. Rotavirus diarrhea most frequently occurred in children 6-17 months of age, and it was more commonly identified in boys (62% of children with rotavirus diarrhea were boys). The seasonal pattern of rotavirus disease mimicked that of diarrheal illness due to all causes, with the peak season for rotavirus disease occurring from November through February (i.e., during the cool, dry season). During the study period, 53 of the children who were hospitalized for diarrhea died. The present study confirms the importance of the etiological role that rotavirus plays in childhood diarrhea.

Drug-resistant tuberculosis in Yangon, Myanmar.

The extent of drug resistant tuberculosis (TB) in the capital city of Myanmar, Yangon has not yet been reported. This study aimed to determine the proportion and pattern of drug resistance to first-line anti-TB drugs, among Mycobacterium tuberculosis complex isolates from sputum smear positive TB patients who attended National TB Programme Yangon centres in April-August and October-December 2002. Drug susceptibility was determined by the Mycobacteria Growth Indicator Tube manual system (Becton Dickinson, MD, USA). Of the 567 patients, sputum specimens from 447 (79%) had a positive culture. Of these, 357 isolates (80%) had a susceptibility test result. Isolates from 76 of 259 (29.3%) new patients and from 45 of 98 (45.9%) previously treated patients were resistant to at least 1 of the anti-TB drugs. Resistance to isoniazid (INH) (22.0% vs 40.8%: new vs previously treated patients) and to > or =2 drugs (17.8% vs 29.6%: new vs previously treated patients) was common. Multidrug- resistant TB (MDR-TB) among new and previously treated patients was 4.2% and 18.4%, respectively. INH-resistant (adjusted OR: 2.0, 95% CI 1.1-3.6) and MDR-TB (adjusted OR: 3.4, 95% CI 1.4-8.3) cases were more likely to have taken anti-TB drugs > or =1 month previously. Collectively, prevalence of MDR-TB and TB resistance to > or =2 drugs are not rare in Yangon.