Insight into genetic diversity of Mycobacterium tuberculosis in Kandy, Sri Lanka reveals predominance of the Euro-American lineage

Hantavirus infection in central Sri Lanka - an unusual clinical presentation: a case report

Hantavirus infections are emerging zoonoses. In Asia, the hantavirus commonly manifests as haemorrhagic fever with renal syndrome (HFRS), apparent with fever, thrombocytopenia and acute kidney injury. There are a few cases with the atypical clinical course with cardiopulmonary symptoms in Asia including Sri Lanka. Here, we report a case of hantavirus infection with an atypical cardiopulmonary syndrome-like illness with serological evidence of the Puumala/Puumala-like virus.

The occurrence rate of Haarlem and Beijing genotypes among Middle Eastern isolates of multi drug resistant Mycobacterium tuberculosis: A systematic review and meta-analysis

Antibiotic resistance is a serious problem that poses a major challenge to tuberculosis control worldwide. Many developing countries still struggle with this infection in term of various aspects as it remains a major health concern. A number of developing countries are located in the Middle East, one of the world's most important regions. The control of this infection remains largely suboptimal despite intensive research in the field, and the mechanisms that lead to its progression have not yet been fully understood. Therefore, TB control must be amended through the identification of new strategies. For this reason, monitoring genetic characterizations of TB strains by molecular typing methods in different geographical regions can be important to setting local programs and global strategies to control TB infection. It is important to know the genotype of Mycobacterium tuberculosis strains to evaluate the occurrence of outbreaks and the transmission of this disease. Beijing and Haarlem genotypes are the most prevalent and, in these families, there is greater association with drug resistance, resulting in more severe forms of TB and higher levels of treatment failure than in other families. The current study is planned to systematically conduct a review using a meta-analysis to show the prevalence of Beijing and Haarlem genotypes in the Middle Eastern MDR-TB cases. M. tuberculosis strains pose particular epidemiological and clinical concerns as they can endanger tuberculosis control programs.

Molecular epidemiology of bovine tuberculosis in Northern Ghana identifies several uncharacterized bovine spoligotypes and suggests possible zoonotic transmission

Objective

We conducted an abattoir-based cross-sectional study in the five administrative regions of Northern Ghana to determine the distribution of bovine tuberculosis (BTB) among slaughtered carcasses and identify the possibility of zoonotic transmission.

Methods

Direct smear microscopy was done on 438 tuberculosis-like lesions from selected cattle organs and cultured on Lowenstein-Jensen media. Acid-fast bacilli (AFB) isolates were confirmed as members of the Mycobacterium tuberculosis complex (MTBC) by PCR amplification of IS6110 and rpoß. Characterization and assignment into MTBC lineage and sub-lineage were done by spoligotyping, with the aid of the SITVIT2, miruvntrplus and mbovis.org databases. Spoligotype data was compared to that of clinical M. bovis isolates from the same regions to identify similarities.

Results

A total of 319/438 (72.8%) lesion homogenates were smear positive out of which, 84.6% (270/319) had microscopic grade of at least 1+ for AFB. Two hundred and sixty-five samples (265/438; 60.5%) were culture positive, of which 212 (80.0%) were MTBC. Approximately 16.7% (34/203) of the isolates with correctly defined spoligotypes were negative for IS6110 PCR but were confirmed by rpoß. Spoligotyping characterized 203 isolates as M. bovis (198, 97.5%), M. caprae (3, 1.5%), M. tuberculosis (Mtbss) lineage (L) 4 Cameroon sub-lineage, (1, 0.5%), and M. africanum (Maf) L6 (1, 0.5%). A total of 53 unique spoligotype patterns were identified across the five administrative regions (33 and 28 were identified as orphan respectively by the SITVIT2 and mbovis.org databases), with the most dominant spoligotype being SIT1037/ SB0944 (77/203, 37.93%). Analysis of the bovine and human M. bovis isolates showed 75% (3/4) human M. bovis isolates sharing the same spoligotype pattern with the bovine isolates.

Conclusion

Our study identified that approximately 29% of M. bovis strains causing BTB in Northern Ghana are caused by uncharacterized spoligotypes. Our findings suggest possible zoonotic transmission and highlight the need for BTB disease control in Northern Ghana.

Molecular epidemiology and drug susceptibility profiles of Mycobacterium tuberculosis complex isolates from Northern Ghana

OBJECTIVE

We conducted a cross-sectional study in the five administrative regions of Northern Ghana to determine the diversity of Mycobacterium tuberculosis complex (MTBC) sub/lineages and their susceptibility to isoniazid (INH) and rifampicin (RIF).

METHODS

Sputum specimens were collected and cultured from 566 pulmonary tuberculosis patients reporting to 17 health facilities from 2015 to 2019. Mycobacterial isolates obtained from solid cultures were confirmed as members of the MTBC by PCR amplification of IS6110 and rpoß and assigned lineages and sub-lineages using spoligotyping.

RESULTS

Of 294 mycobacterial isolates recovered, MTBC species identified were: M. tuberculosis sensu stricto (Mtbss) 241 (82.0%), M. africanum 41 (13.9%) and M. bovis four (1.4%) with eight (2.7%) unidentified. The human-adapted lineages (L) identified (N=279) were L1 (8/279, 2.9%), L2 (15/279, 5.4%), L3 (7/279, 2.5%), L4 (208/279, 74.5%), L5 (13/279, 4.7%) and L6 (28/279, 10.0%) with three unidentified lineages. Among the 208 L4, the dominant sub-lineages in the region were the Cameroon 120/208 (57.7%) and Ghana 50/208 (24.0%). We found 4.4% (13/294) and 0.7% (2/294) of the patients infected with MTBC isolates resistant to INH only and RIF only, respectively, with 2.4% (7/294) being infected with MDR strains. Whereas L6 was associated with the elderly, we identified that the Ghana sub-lineage of L4 was associated with both INH and MDR (p<0.05), making them important TB pathogens in Northern Ghana and a growing public health concern.

Insight into population structure of Mycobacterium tuberculosis isolates in the multiethnic province of Alborz, Iran

Background and Objectives:

Genetic diversity of Mycobacterium tuberculosis clinical isolates from tuberculosis patients in the multiethnic province of Alborz, Iran was assessed.

Materials and Methods:

A total of 17 isolates in the period of 2012–2013 were collected and subjected to a Multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) consisted of 6 variable numbers of tandem repeats (VNTRs) including ETR-A, ETR-B, ETR-C, ElTR-D, ETR-E, ETR-F, 5 Mycobacterial Interspersed Repetitive Units including MIRU10, MIRU16, MIRU26, MIRU39, MIRU40, and 1 Queen University of Belfast locus, QUB11.

Results:

This classified all isolates into 17 distinct MIRU-VNTR types, a reflection of a highly heterogenic population. Within the 12 used VNTR loci, ten proved highly or moderately discriminant according to the calculated HGDI scores. No cluster of isolates was identified in the study panel, giving a clustering rate of 0%, several events of SVL (N=5) and DVL (N=4) and TVL (N=3) were detected.

Conclusion:

The greater heterogeneity observed here by MLVA-VNTR analysis is most likely due to limited background data in the study region rather than a genuine more heterogeneous population compared to other provinces of the country.

A pilot study on the genetic diversity of Mycobacterium tuberculosis complex strains from tuberculosis patients in the Littoral region of Cameroon

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The Xpert MTB/RIF provides a rapid MDR detection and management of TB patients.

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The Cameroon family is the predominant genotype in the Littoral region of Cameroon.

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The UgandaI sublineage is likely associated with RIF resistance in the study area.

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The mapping of the UgandaI sublineage is essential for MDR control in the country.

Background

The re-emergence of tuberculosis (TB) worldwide, compounded by multi-drug resistance (MDR) of the causative agents constitutes a major challenge to the management of the disease. Rapid diagnosis and accurate strain identification are pivotal to the control of the disease. This pilot study investigated the genetic diversity of Mycobacterium tuberculosis complex (MTBC) strains from TB patients in the Littoral region of Cameroon as well as their resistance to rifampicin (RIF).

Patients and methods

This was a cross sectional hospital-based study carried out between January and December 2017 and including 158 isolates from sputum smear positive individuals [105 (66.5%) males and 53 (33.5%) females]. Sputum samples were tested using Xpert MTB/RIF, followed by culture on Lowenstein–Jensen medium. Isolates were further subjected to molecular characterization using IS6110 typing, deletion analysis and spoligotyping.

Results

Thirteen (8.8%) of the 147 isolates with susceptibility results available were resistant to RIF. Drug resistance occurred in 5/50 (10%) female compared to 8/97 (8.2%) male (OR, 0.81; 0.25–2.62; p = 0.764), and there was no significant difference across the age ranges (p = 0.448). On the other hand, RIF resistance was associated (OR, 0.18, 95%CI, 0.05–0.69; p = 0.023) with previously treated patients [(4/14 (28.6%)] compared to new ones [9/133 (6.8%)]. The 150 identified lineages included among others 54 (36%) Cameroon, 18 (12%) UgandaI, 32 (21.3%) Haarlem, 17 (11.3%) Ghana, 9(6%) West African 1, 7(4.7%) Delhi/CAS, 4 (2.7%) LAM and 3 (2%) UgandaII. Of the 150 isolates, the major cluster was the Cameroon SIT 61, with 43(28.7%) isolates. Six (35.3%) of the 17 UgandaI sub-lineage were RIF resistant (OR, 9.58; 95%CI, 2.74–33.55, p = 0.001).

Conclusion

The cosmopolitan Littoral region presents with a wide Mycobacterium tuberculosis (MTB) strains diversity and the UgandaI sub-lineage likely associated with RIF resistance. Understanding the spread of this clade through surveillance will enhance TB control in the region.

Is International Travel an Emerging Issue on Transmission of Beijing Lineage Mycobacterium tuberculosis?

Mycobacterium tuberculosis belonging to Beijing sublineage (BL) is associated with high tuberculosis (TB) transmission, multidrug resistance, and adverse treatment outcomes. Sri Lanka experiences an increase in the number of travellers/workers to and from high TB-burden countries, and there is risk of getting BL strains imported into the country. In this context, a cohort study was conducted to assess the prevalence of BL strains among pulmonary tuberculosis (PTB) patients in the Kandy district of Sri Lanka (a popular tourist destination) and its association with patients' sociodemographic and clinical characteristics. The study population included sputum smear-positive PTB patients diagnosed from February 2018-July 2019. Fresh sputum samples were collected for culturing and conducted polymerase chain reaction using BL-specific primers. Among the 101 patients recruited, presence of BL strains could be ascertained in 94 patients of which 24 (26%; 95% CI: 18%-35%) had BL strains. Prevalence of BL strains was higher among those with high sputum smear grades (2+ and 3+) (P < 0.05) and those who had travelled abroad (P < 0.05). The prevalence was also higher among young people (aged <35 years). Treatment success rates were similar in patients with (83%) and without BL strains (83% vs. 81%; P value = 0.8375). The prevalence of BL strains in Kandy, Sri Lanka, was high compared to previously reported figures in Sri Lanka, and the percentage drives closer to the countries in South East Asia. International travel raises itself as an emerging issue in BL transmission urging the need of policies and practices in immigration/emigration strategies. The study findings have the potential to alter the TB epidemiology in the country and might represent the situation in other underexplored countries as well. Therefore, it is important to monitor the trends and factors related to the prevalence of Beijing strains globally and make decisions as a whole.