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MDR-MTB strains of the Beijing genotype might be spreading in Myanmar and present a major challenge to TB control in this country.

Background Plasmodium falciparum merozoite surface protein-1 (PfMSP-1) and -2 (PfMSP-2) are major blood-stage vaccine candidate antigens. Understanding the genetic diversity of the genes, pfmsp - 1 and pfmsp - 2 , is important for recognizing the genetic structure of P. falciparum , and the development of an effective vaccine based on the antigens. In this study, the genetic diversities of pfmsp - 1 and pfmsp - 2 in the Myanmar P. falciparum were analysed. Methods The pfmsp - 1 block 2 and pfmsp - 2 block 3 regions were amplified by polymerase chain reaction from blood samples collected from Myanmar patients who were infected with P. falciparum in 2013–2015. The amplified gene fragments were cloned into a T&A vector, and sequenced. Sequence analysis of Myanmar pfmsp - 1 block 2 and pfmsp - 2 block 3 was performed to identify the genetic diversity of the regions. The temporal genetic changes of both pfmsp - 1 and pfmsp - 2 in the Myanmar P. falciparum population, as well as the polymorphic diversity in the publicly available global pfmsp - 1 and pfmsp - 2 , were also comparatively analysed. Results High levels of genetic diversity of pfmsp - 1 and pfmsp - 2 were observed in the Myanmar P. falciparum isolates. Twenty-eight different alleles of pfmsp - 1 (8 for K1 type, 14 for MAD20 type, and 6 for RO33 type) and 59 distinct alleles of pfmsp - 2 (18 for FC27, and 41 for 3D7 type) were identified in the Myanmar P. falciparum population in amino acid level. Comparative analyses of the genetic diversity of the Myanmar pfmsp - 1 and pfmsp - 2 alleles in the recent (2013–2015) and past (2004–2006) Myanmar P. falciparum populations indicated the dynamic genetic expansion of the pfmsp - 1 and pfmsp - ...

The Beijing genotype of Mycobacterium tuberculosis is known to be a worldwide epidemic clade. It is suggested to be a possibly resistant clone against BCG vaccination and is also suggested to be highly pathogenic and prone to becoming drug resistant. Thus, monitoring the prevalence of this lineage seems to be important for the proper control of tuberculosis. The Rv0679c protein of M. tuberculosis has been predicted to be one of the outer membrane proteins and is suggested to contribute to host cell invasion. Here, we conducted a sequence analysis of the Rv0679c gene using clinical isolates and found that a single nucleotide polymorphism, C to G at position 426, can be observed only in the isolates that are identified as members of the Beijing genotype family. Here, we developed a simple multiplex PCR assay to detect this point mutation and applied it to 619 clinical isolates. The method successfully distinguished Beijing lineage clones from non-Beijing strains with 100% accuracy. This simple, quick, and cost-effective multiplex PCR assay can be used for a survey or for monitoring the prevalence of Beijing genotype M. tuberculosis strains.

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Diagnostic testing of blood samples for parasite antigen Og4C3 is used to assess Wuchereria bancrofti in endemic populations. However, the Tropbio ELISA recommends that plasma and dried blood spots (DBS) prepared using filter paper be used at different dilutions, making it uncertain whether these two methods and dilutions give similar results, especially at low levels of residual infection or resurgence during the post-program phase. We compared results obtained using samples of plasma and DBS taken simultaneously from 104 young adults in Myanmar in 2014, of whom 50 (48.1%) were positive for filariasis antigen by rapid antigen test. Results from DBS tests at recommended dilution were significantly lower than results from plasma tested at recommended dilution, with comparisons between plasma and DBS at unmatched dilutions yielding low sensitivity and negative predictive values of 60.0% and 70.6% respectively. While collection of capillary blood on DBS is cheaper and easier to perform than collecting plasma or serum, and does not need to be stored frozen, dilutions between different versions of the test must be reconciled or an adjustment factor applied.

25The number of multi-drug-resistant tuberculosis (MDR-TB) cases is rising worldwide. As a 26 countermeasure against this situation, the implementation of rapid molecular tests to identify MDR-27 TB would be effective. To develop such tests, information on the frequency and distribution of

Recent advances in electron microscopy and tomography have revealed distinct virus-induced endoplasmic reticulum (ER) structures unique for dengue virus (DV) and other flaviviruses in cell culture models, including hepatocytes. These altered ultrastructures serve as sites for viral replication. In this study, we used transmission electron microscopy to investigate whether such structures were present in the liver of fatal dengue hemorrhagic fever (DHF) autopsy cases. In parallel, electron microscopic examination of suckling mouse brains experimentally infected with DV was performed as an in vivo model of acute DV infection. Typical features of ER changes containing abundance of replicative virions were observed in neurons and microglia of DV-infected suckling mouse brains (SMB). This indicated that the in vivo DV infection could induce similar viral replication structures as previously described in the in vitro DV-infected cell model. Nevertheless, liver tissues from autopsy of patients who died of DHF showed scant changes of ER membrane structures and rare particles of virions in hepatocytes, despite overwhelming evidence for the presence of viral antigens and RNA–indicating active virus replication. Instead hepatocytes contained an abundance of steatotic vesicles and structural damages. This lack of structural changes indicative of virus replication in human hepatocytes is discussed.