Clinical Relevance of Nontuberculous Mycobacteria, Oman

Little is known about the clinical relevance of nontuberculous mycobacteria (NTM) in the Arabian Peninsula. We assessed the prevalence and studied a random sample of isolates at a reference laboratory in Muscat, Oman. NTM cause disease in this region, and their prevalence has increased

Clinical Relevance of Nontuberculous Mycobacteria, Oman

Little is known about the clinical relevance of nontuberculous mycobacteria (NTM) in the Arabian Peninsula. We assessed the prevalence and studied a random sample of isolates at a reference laboratory in Muscat, Oman. NTM cause disease in this region, and their prevalence has increased

Molecular identification and characterization of two proposed new enterovirus serotypes, EV74 and EV75

Fil: Oberste, M. Steven. Centers for Disease Control and Prevention. Respiratory and Enteric Viruses Branch; Estados Unidos.Fil: Michele, Suzanne M. Centers for Disease Control and Prevention. Respiratory and Enteric Viruses Branch; Estados Unidos.Fil: Maher, Kaija. Centers for Disease Control and Prevention. Respiratory and Enteric Viruses Branch; Estados Unidos.Fil: Schnurr, David. California Department of Health Services. Viral and Rickettsial Disease Laboratory; Estados Unidos.Fil: Cisterna, Daniel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Junttila, Nina. Swedish Institute for Disease Control. Department of Virology; Suecia.Fil: Uddin, Moyez. Institute of Public Health; Bangladesh.Fil: Chomel, Jean-Jacques. Centre National de Référence des Entérovirus; Francia.Fil: Lau, Chi-Shan. Queen Mary Hospital. Department of Health; China.Fil: Ridha, Walid. National Polio Laboratory; Irak.Fil: Al-Busaidy, Suleiman. Ministry of Health. Department of Laboratories; Oman.Fil: Norder, Helene. Swedish Institute for Disease Control. Department of Virology; Suecia.Fil: Magnius, Lars O. Swedish Institute for Disease Control. Department of Virology; Suecia.Fil: Pallansch, Mark A. Centers for Disease Control and Prevention. Respiratory and Enteric Viruses Branch; Estados Unidos.Sequencing of the gene that encodes the capsid protein VP1 has been used as a surrogate for antigenic typing in order to distinguish enterovirus serotypes; three new serotypes were identified recently by this method. In this study, 14 enterovirus isolates from six countries were characterized as members of two new types within the species Human enterovirus B, based on sequencing of the complete capsid-encoding (P1) region. Isolates within each of these two types differed significantly from one another and from all other known enterovirus serotypes on the basis of sequences that encode either VP1 alone or the entire P1 region. Members of each type were greater than or equal to 77(.)2% identical to one another (89(.)5% amino acid identity) in VP1, but members of the two different types differed from one another and from other enteroviruses by greater than or equal to 31% in nucleotide sequence (25% amino acid sequence difference), indicating that the two groups represent separate new candidate enterovirus types. The complete P1 sequences differed from those of all other enterovirus serotypes by greater than or equal to 31% (26% amino acid sequence difference), but were highly conserved within a serotype (< 8% amino acid sequence difference). Phylogenetic analyses demonstrated that isolates of the same serotype were monophyletic in both VP1 and the capsid as a whole, as shown previously for other enterovirus serotypes. This paper proposes that these 14 isolates should be classified as members of two new human enterovirus types, enteroviruses 74 and 75 (EV74 and EV75)

Standardization and international multicenter validation of a PulseNet pulsed-field gel electrophoresis protocol for subtyping Shigella flexneri isolates

Fil: Pichel, Mariana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Brengi, Silvina P. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Cooper, Kara L. F. Centers for Disease Control and Prevention; Estados Unidos.Fil: Ribot, Efrain M. Centers for Disease Control and Prevention; Georgia.Fil: Al-Busaidy, Suleiman. Central Public Health Laboratory; Omán.Fil: Araya, Pamela. Instituto de Salud Pública de Chile; Chile.Fil: Fernández, Jorge. Instituto de Salud Pública de Chile; Chile.Fil: Vaz, Tania Ibelli. Instituto Adolfo Lutz; Brazil.Fil: Kam, Kai Man. Public Health Laboratory Centre; Japón.Fil: Morcos, Myriam. Regional Center at the U.S. Naval Medical Research Unit #3 (NAMRU-3). Global Disease Detection (GDD); Egipto.Fil: Nielsen, Eva M. Statens Serum Institut; Dinamarca.Fil: Nadon, Celine. National Microbiology Laboratory; Canadá.Fil: Pimentel, Guillermo. Regional Center at the U.S. Naval Medical Research Unit #3 (NAMRU-3). Global Disease Detection (GDD); Egipto.Fil: Pérez-Gutiérrez, Enrique. PAHO/WHO. Health Surveillance; Panamá.Fil: Gerner-Smidt, Peter. Centers for Disease Control and Prevention; Georgia.Fil: Binsztein, Norma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Shigella flexneri is one of the agents most frequently linked to diarrheal illness in developing countries and often causes outbreaks in settings with poor hygiene or sanitary conditions. Travel is one of the means by which S. flexneri can be imported into developed countries, where this pathogen is not commonly seen. A robust and discriminatory subtyping method is needed for the surveillance of S. flexneri locally and regionally, and to aid in the detection and investigation of outbreaks. The PulseNet International network utilizes standardized pulsedfield gel electrophoresis (PFGE) protocols to carry out laboratory-based surveillance of foodborne pathogens in combination with epidemiologic data. A multicenter validation was carried out in nine PulseNet laboratories located in North and South America, Europe, and Asia, and it demonstrated that a new protocol is highly robust and reproducible for subtyping of S. flexneri. This protocol, already approved for PulseNet laboratories, applies NotI and XbaI as primary and secondary restriction enzymes, respectively, under electrophoresis conditions of initial switch time of 5 s to final switch time of 35 s, at 6 volts/cm

Molecular Epidemiology and Genotyping of Hepatitis B Virus of HBsAg-Positive Patients in Oman

Background: Hepatitis B virus (HBV) infection is a major global health burden with distinct geographic public health significance. Oman is a country with intermediate HBV carrier prevalence; however, little is known about the incidence of HBV variants in circulation. We investigated the HBV genotype distribution, the occurrence of antiviral resistance, and HBV surface antigen (HBsAg) escape mutations in HBsAg-positive patients in Oman. Methods: Serum samples were collected from 179 chronically HBV-infected patients enrolled in various gastroenterology clinics in Oman. HBV genotypes were determined by sequencing and phylogenetic analysis. Mutations in the HBV polymerase and the HBsAg gene were characterized by mutational analysis. Results: HBV genotypes D (130/170; 76.47%) and A (32/170; 18.28%) are predominant in Oman. The HBV genotypes C and E were less frequent (each 1.18%), while the HBV genotypes B, G, F, and H were not detected. Four patients revealed HBV genotype mixtures (HBV-A/D and D/C). The analyses of vaccine escape mutations yield that 148/170 (87.06%) HBV sequences were wild type. 22/170 (12.94%) HBV sequences showed mutations in the “a” determinant of the HBsAg domain. Two patients showed the described HBV vaccine escape mutation sP120T. 8/146 (5.48%) HBV isolates harbored mutations in the HBV polymerase known to confer resistance against antiviral therapy. Especially the lamivudine resistance mutations rtL180M/rtM204V and rtM204I were detected. Conclusion: This study shows the distribution of HBV genotypes, therapy resistance, and vaccine escape mutations in HBV-infected patients in Oman. Our findings will have a major impact on therapy management and diagnostics of chronic HBV infections in Oman to control HBV infection in this intermediate HBV-endemic country

Analysis of antiviral therapy resistant mutations of Omani HBV isolates.

<p>The amino acid sequences of the HBV polymerase (reverse transcriptase region; aa rtM1 to rtL275) of the Omani resistant mutation isolates were aligned with the corresponding region of the reference sequences (HBV-genotypes A to H; GenBank accession numbers are denoted) by ClustalW with Neighbor Joining method and 1000 bootstrap replicates. Described antiviral resistant mutations were highlighted and denoted at the top (e.g., L80V).</p

Clinical profiles of HBsAg-positive patients of Oman.

<p>Clinical profiles of HBsAg-positive patients of Oman.</p

Analysis of antiviral therapy resistant mutations of Omani HBV isolates.

<p>The amino acid sequences of the HBV polymerase (reverse transcriptase region; aa rtM1 to rtL275) of the Omani resistant mutation isolates were aligned with the corresponding region of the reference sequences (HBV-genotypes A to H; GenBank accession numbers are denoted) by ClustalW with Neighbor Joining method and 1000 bootstrap replicates. Described antiviral resistant mutations were highlighted and denoted at the top (e.g., L80V).</p