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1.
Int J Mol Sci ; 25(3)2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38339222

RESUMEN

Hypervirulent Klebsiella pneumoniae (hvKp) is a variant that has been increasingly linked to severe, life-threatening infections including pyogenic liver abscess and bloodstream infections. HvKps belonging to the capsular serotypes K1 and K2 have been reported worldwide, however, very scarce studies are available on their genomics and virulence. In the current study, we report four hypermucoviscous extended-spectrum ß-lactamase-producing hvKp clinical strains of capsular serotype K1 and K2 isolated from pus and urine of critically ill patients in tertiary care hospitals in Oman. These strains belong to diverse sequence types (STs), namely ST-23(K1), ST-231(K2), ST-881(K2), and ST-14(K2). To study their virulence, a Galleria mellonella model and resistance to human serum killing were used. The G. mellonella model revealed that the K1/ST-23 isolate was the most virulent, as 50% of the larvae died in the first day, followed by isolate K2/ST-231 and K2/ST-14, for which 75% and 50% of the larvae died in the second day, respectively. Resistance to human serum killing showed there was complete inhibition of bacterial growth of all four isolates by the end of the first hour and up to the third hour. Whole genome sequencing (WGS) revealed that hvKp strains display a unique genetic arrangement of k-loci. Whole-genome single-nucleotide polymorphism-based phylogenetic analysis revealed that these hvKp isolates were phylogenetically distinct, belonging to diverse clades, and belonged to different STs in comparison to global isolates. For ST-23(K1), ST-231(K2), ST-881(K2), and ST-14(K2), there was a gradual decrease in the number of colonies up to the second to third hour, which indicates neutralization of bacterial cells by the serum components. However, this was followed by a sudden increase of bacterial growth, indicating possible resistance of bacteria against human serum bactericidal activity. This is the first report from Oman detailing the WGS of hvKp clinical isolates and assessing their resistance and virulence genomics, which reinforce our understanding of their epidemiology and dissemination in clinical settings.


Asunto(s)
Klebsiella pneumoniae , Factores de Virulencia , Humanos , Serogrupo , Filogenia , Virulencia/genética , Factores de Virulencia/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico
2.
Foodborne Pathog Dis ; 19(5): 332-340, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35325576

RESUMEN

PulseNet International (PNI) is a global network of 88 countries who work together through their regional and national public health laboratories to track foodborne disease around the world. The vision of PNI is to implement globally standardized surveillance using whole genome sequencing (WGS) for real-time identification and subtyping of foodborne pathogens to strengthen preparedness and response and lower the burden of disease. Several countries in North America and Europe have experienced significant benefits in disease mitigation after implementing WGS. To broaden the routine use of WGS around the world, challenges and barriers must be overcome. We conducted this study to determine the challenges and barriers countries are encountering in their attempts to implement WGS and to identify how PNI can provide support to improve and become a better integrated system overall. A survey was designed with a set of qualitative questions to capture the status, challenges, barriers, and successes of countries in the implementation of WGS and was administered to laboratories in Africa, Asia-Pacific, Latin America and the Caribbean, and Middle East. One-third of respondents do not use WGS, and only 8% reported using WGS for routine, real-time surveillance. The main barriers for implementation of WGS were lack of funding, gaps in expertise, and training, especially for data analysis and interpretation. Features of an ideal system to facilitate implementation and global surveillance were identified as an all-in-one software that is free, accessible, standardized and validated. This survey highlights the minimal use of WGS for foodborne disease surveillance outside the United States, Canada, and Europe to date. Although funding remains a major barrier to WGS-based surveillance, critical gaps in expertise and availability of tools must be overcome. Opportunities to seek sustainable funding, provide training, and identify solutions for a globally standardized surveillance platform will accelerate implementation of WGS worldwide.


Asunto(s)
Países en Desarrollo , Enfermedades Transmitidas por los Alimentos , Brotes de Enfermedades , Enfermedades Transmitidas por los Alimentos/epidemiología , Genoma Bacteriano , Humanos , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Secuenciación Completa del Genoma
3.
Qatar Med J ; 2022(1): 13, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35309111

RESUMEN

Melioidosis is a severe disease that can affect humans and animals. It is caused by Burkholderia pseudomallei, which is an environmental aerobic gram negative bacteria. Despite being endemic in Southeast Asia and Northern Australia, many cases have been reported from different regions, including the Middle East. This is the third imported case of B. pseudomallei from Oman in a 46-year-old Indian male with left knee septic arthritis in less than three weeks after arrival in Oman. He underwent open arthrotomy, and his synovial fluid culture grew a bacteria with dry, pink colonies that were oxidase positive, susceptible to amoxicillin-clavulanic, identified by API NE as B. pseudomallei, and confirmed by molecular tests. This single case report highlights the urgent need to increase molecular diagnostic capacity and improve public health surveillance while maintaining a one health tripartite approach.

5.
J Clin Microbiol ; 53(3): 896-903, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25568439

RESUMEN

The molecular epidemiology and mechanisms of resistance of carbapenem-resistant Acinetobacter baumannii (CRAB) were determined in hospitals in the states of the Cooperation Council for the Arab States of the Gulf (Gulf Cooperation Council [GCC]), namely, Saudi Arabia, United Arab Emirates, Oman, Qatar, Bahrain, and Kuwait. Isolates were subjected to PCR-based detection of antibiotic resistance genes and repetitive sequence-based PCR (rep-PCR) assessments of clonality. Selected isolates were subjected to multilocus sequence typing (MLST). We investigated 117 isolates resistant to carbapenem antibiotics (either imipenem or meropenem). All isolates were positive for OXA-51. The most common carbapenemases were the OXA-23-type, found in 107 isolates, followed by OXA-40-type (OXA-24-type), found in 5 isolates; 3 isolates carried the ISAba1 element upstream of blaOXA-51-type. No OXA-58-type, NDM-type, VIM-type, or IMP-type producers were detected. Multiple clones were detected with 16 clusters of clonally related CRAB. Some clusters involved hospitals in different states. MLST analysis of 15 representative isolates from different clusters identified seven different sequence types (ST195, ST208, ST229, ST436, ST450, ST452, and ST499), as well as three novel STs. The vast majority (84%) of the isolates in this study were associated with health care exposure. Awareness of multidrug-resistant organisms in GCC states has important implications for optimizing infection control practices; establishing antimicrobial stewardship programs within hospital, community, and agricultural settings; and emphasizing the need for establishing regional active surveillance systems. This will help to control the spread of CRAB in the Middle East and in hospitals accommodating transferred patients from this region.


Asunto(s)
Infecciones por Acinetobacter/epidemiología , Acinetobacter baumannii/clasificación , Acinetobacter baumannii/enzimología , Antibacterianos/farmacología , Carbapenémicos/farmacología , Resistencia betalactámica , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/aislamiento & purificación , Preescolar , Análisis por Conglomerados , Femenino , Genotipo , Hospitales , Humanos , Lactante , Masculino , Medio Oriente/epidemiología , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Reacción en Cadena de la Polimerasa , beta-Lactamasas/genética
6.
Antimicrob Agents Chemother ; 58(6): 3085-90, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24637692

RESUMEN

The molecular epidemiology and mechanisms of resistance of carbapenem-resistant Enterobacteriaceae (CRE) were determined in hospitals in the countries of the Gulf Cooperation Council (GCC), namely, Saudi Arabia, United Arab Emirates, Oman, Qatar, Bahrain, and Kuwait. Isolates were subjected to PCR-based detection of antibiotic-resistant genes and repetitive sequence-based PCR (rep-PCR) assessments of clonality. Sixty-two isolates which screened positive for potential carbapenemase production were assessed, and 45 were found to produce carbapenemase. The most common carbapenemases were of the OXA-48 (35 isolates) and NDM (16 isolates) types; 6 isolates were found to coproduce the OXA-48 and NDM types. No KPC-type, VIM-type, or IMP-type producers were detected. Multiple clones were detected with seven clusters of clonally related Klebsiella pneumoniae. Awareness of CRE in GCC countries has important implications for controlling the spread of CRE in the Middle East and in hospitals accommodating patients transferred from the region.


Asunto(s)
Proteínas Bacterianas/genética , Infecciones por Escherichia coli/epidemiología , Proteínas de Escherichia coli/genética , Escherichia coli/enzimología , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/enzimología , beta-Lactamasas/genética , Antibacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Carbapenémicos/metabolismo , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/metabolismo , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Medio Oriente/epidemiología , Oxitocina/análogos & derivados , Oxitocina/metabolismo , beta-Lactamasas/metabolismo
7.
Int J Infect Dis ; 141S: 107002, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38479577

RESUMEN

OBJECTIVES: To review the evidence that migrants from tuberculosis (TB) high-incidence countries migrating to TB low-incidence countries significantly contribute to active TB cases in the counties of destination, primarily through reactivation of latent TB. METHODS: This is a narrative review. The different screening programs in the countries of destination are reviewed either based on screening and preventive treatment of latent TB pre or more commonly - post arrival. RESULTS: Screening can be performed using interferon-gamma release assays (IGRA) or tuberculin skin tests (TST). Preventive treatment of latent TB is using either monotherapy with isoniazid, or in combination with rifampicin or rifapentine. We discuss the ethical issues of preventive treatment in asymptomatic individuals and how these are addressed in different screening programs. CONCLUSION: Screening migrants from TB high endemic countries to TB low endemic countries is beneficial. There is a lack of standardization and agreement on screening protocols, follow up and treatment.


Asunto(s)
Tuberculosis Latente , Migrantes , Tuberculosis , Humanos , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/epidemiología , Ensayos de Liberación de Interferón gamma/métodos , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Prueba de Tuberculina/métodos , Tamizaje Masivo/métodos
9.
Int J Infect Dis ; 130 Suppl 1: S4-S11, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37075829

RESUMEN

OBJECTIVES: Mycobacterium tuberculosis (MTB) is a global public health issue. Although Oman reduced the burden of tuberculosis (TB) by 85% in under 25 years, the annual incidence rate remains stagnant. Whole genome sequencing (WGS) is used to investigate the transmission dynamics of MTB complex. This study aimed to resolve traditional genotype clusters and exploring the geospatial distribution to understand the epidemiology of TB in Oman. METHODS: Confirmed cases with spoligotyping clusters were randomly selected. WGS of 70 isolates were selected for final analysis. Correlation of epidemiological and geospatial data was conducted. RESULTS: A total of 233 cases were registered in 2021; 169 had confirmed growth, with an incidence rate of 5.2/100,000 population for 2021. A total of 70 genomes were analyzed, and five large clusters and three medium clusters were identified. The lineages L1, L2, L3, and L4 and several sublineages belonging to the Indo-Oceanic family and East African Indian family were identified as predominant in Oman. There were no multidrug-resistant cases identified. CONCLUSION: There is a considerable genetic variation among the strains in Oman. This predominance could be linked with the high percentage of non-national population, which represents different countries and frequent traveling to high TB burden countries. WGS combined with geospatial investigations of MTB are required to better understand the disease transmission in Oman, which will support TB elimination efforts.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Mycobacterium tuberculosis/genética , Omán/epidemiología , Tuberculosis/microbiología , Genotipo , Genómica , Secuenciación Completa del Genoma , Epidemiología Molecular , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Antituberculosos/uso terapéutico
10.
Influenza Other Respir Viruses ; 17(12): e13233, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38098648

RESUMEN

Introduction: Severe acute respiratory illness (SARI) is a potentially lethal condition, necessitating thorough medical care. COVID-19 underscored the SARI threat, but other high-risk pathogens require monitoring alongside SARS-CoV-2. Oman instituted a comprehensive testing system to gauge the prevalence of these pathogens between 2017 and 2021, aiding resource allocation and public health responses to potential respiratory pathogen outbreaks. Methods: Samples from SARI cases admitted to ICU were tested for pathogens using the Fast-Track Diagnostic (FTD) molecular assay, a respiratory virus panel (RVP) that tests for 21 pathogens, including 20 viruses, by qPCR. Results: Between 2017 and 2022, ~30 000 samples were analysed using the RVP panel. Among SARI patients, 8%-42% tested positive for respiratory pathogens, with 4% showing multiple infectious agents, especially in children under 10. A drop in positivity during 2020-2021 can be attributed to SARS-CoV-2 control measures, followed by a rebound in infections in early 2022. Discussion: The COVID-19 pandemic heightened awareness of respiratory pathogens' spread without adequate control measures. Influenza A/B, human rhinoviruses and respiratory syncytial virus constituted over 50% of severe acute respiratory illness cases in Oman over the past 5 years. During the pandemic, the incidence of these infections significantly declined, demonstrating the efficacy of COVID-19 prevention measures in reducing spread of other pathogens.


Asunto(s)
COVID-19 , Gripe Humana , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Virus , Niño , Humanos , COVID-19/epidemiología , Pandemias , Omán/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , SARS-CoV-2 , Virus/genética , Gripe Humana/epidemiología
11.
Microbiol Spectr ; : e0242023, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37768070

RESUMEN

Tuberculosis (TB) originating from expatriates that hail from high TB-burden countries is hypothesized to play a role in continued TB transmission in Oman. Here, we used whole-genome sequencing (WGS) to assess national TB transmission dynamics. The annual incidence per 100,000 population per year was calculated for nationals and expatriates. A convenience sample of Mycobacterium tuberculosis (MTB) isolates from 2018 to 2019 was sequenced and analyzed with publicly available TB sequences from Bangladesh, Tanzania, the Philippines, India, and Pakistan. Relatedness was assessed by generating core-genome single nucleotide polymorphism (SNP) distances. The incidence of TB was five cases per 100,000 persons in 2018 and seven cases per 100,000 persons in 2020 (R2 = 0.34, P = 0.60). Incidence among nationals was 3.9 per 100,000 persons in 2018 and 3.5 per 100,000 persons in 2020 (R2 = 0.20, P = 0.70), and incidence among expatriates was 7.2 per 100,000 persons in 2018 and 12.7 per 100,000 persons in 2020 (R2 = 0.74, P = 0.34). Sixty-eight local MTB isolates were sequenced and analyzed with 393 global isolates. Isolates belonged to nine distinct spoligotypes. Two isolates, originating from an expatriate and an Omani national, were grouped into a WGS-based cluster (SNP distance < 12), which was corroborated by an epidemiological investigation. Relatedness of local and global isolates (SNP distance < 100) was also seen. The relatedness between MTB strains in Oman and those in expatriate countries of origin can aid inform TB control policy. Our results provide evidence that WGS can complement epidemiological analysis to achieve the End TB strategy goal in Oman. IMPORTANCE Tuberculosis (TB) incidence in Oman remains above national program control targets. TB transmission originating from expatriates from high TB-burden countries has been hypothesized to play a role. We used whole-genome sequencing (WGS) to assess TB transmission dynamics between expatriates and Omani nationals to inform TB control efforts. Available Mycobacterium tuberculosis isolates from 2018 to 2019 underwent WGS and analysis with publicly available TB sequences from Bangladesh, the Philippines, India, and Pakistan to assess for genetic relatedness. Our analysis revealed evidence of previously unrecognized transmission between an expatriate and an Omani national, which was corroborated by epidemiological investigation. Analysis of local and global isolates revealed evidence of distant relatedness between local and global isolates. Our results provide evidence that WGS can complement classic public health surveillance to inform targeted interventions to achieve the End TB strategy goal in Oman.

12.
Oman Med J ; 38(5): e559, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37916129

RESUMEN

Streptococcus agalactiae is known to cause invasive infections in risk groups such as pregnant women, newborns, and immunosuppressed patients but it is uncommon in older children. We describe a case of recurrent infective endocarditis due to S. agalactiae in an 11-year-old boy with Loeys-Dietz syndrome who was successfully treated with long-term antimicrobial therapy for one year.

13.
J Epidemiol Glob Health ; 13(4): 774-781, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37698781

RESUMEN

BACKGROUND: HCV infection in hemodialysis units is a significant cause of morbidity and mortality. The risk of HCV infection among dialysis patients is higher compared to the general population due to high potential blood exposures in hemodialysis settings. This study aims to assess the national HCV seroprevalence in selected dialysis units and to determine the risk factors for acquiring HCV infection. METHODS: This cross-sectional study was conducted from 1 January to 31 March 2021. A total of 734 patients from 11 hemodialysis centers in Oman were included. Samples were tested simultaneously for HCV antibodies and HCV RNA. HCV genotyping was determined in all viremic patients. Demographic and hemodialysis center related data were gathered and their association with the positive HCV serology were explored using univariate and multivariate logistic regression analysis. RESULTS: Out of 800 patients selected from 11 dialysis units for the study, 734 patients (91.8%) were included. The overall seroprevalence of HCV infection among hemodialysis patients was 5.6%. (41/734). HCV RNA was detected in 31.7% (13/41) of seropositive hemodialysis patients. The most common genotype was subtype 1a, followed by subtype 3. Variables associated with high HCV prevalence were family history of HCV and duration of dialysis. CONCLUSION: The prevalence of infection within hemodialysis patients in Oman has significantly decreased but remained higher than the general population. Continuous monitoring and follow-up, including periodic serosurvey and linkage to care and treatment are recommended. Additionally, practice audits are recommended for identifying gaps and ensuring sustainability of best practices and further improvement.


Asunto(s)
Hepacivirus , Hepatitis C , Humanos , Hepacivirus/genética , Estudios Transversales , Estudios Seroepidemiológicos , Omán/epidemiología , Hepatitis C/epidemiología , Diálisis Renal , Factores de Riesgo , Prevalencia , ARN
14.
J Epidemiol Glob Health ; 12(3): 311-315, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35643822

RESUMEN

OBJECTIVE: The primary objective of our study was to estimate the prevalence of hepatitis B infection among pregnant women in Oman. The secondary objectives were to test for other hepatitis B virus (HBV) serological markers and to determine hepatitis B viral load. METHODS: In this cross-sectional study conducted from June 2019 to December 2020, we randomly selected 2210 Omani women who attended antenatal clinics across the country. Pregnant women were tested for HBV surface antigen (HBsAg) using a commercial enzyme immunoassay; those who tested positive were further analyzed for other HBV serological markers: HBV core total antibody (anti-HBc), HBV core antibody IgM (immunoglobulin M) (anti-HBc IgM), hepatitis B virus e antigen (HBeAg) and hepatitis B virus e antibody (anti-HBe). They were also tested for hepatitis B viral load. RESULTS: This study included 2210 women with a mean age of 39 years. Ninety-five percent of the women who were invited to participate consented and were included in the study. Thirty-three (1.49%) tested positive for HBsAg. All participants tested negative for HBeAg and anti-HBc IgM and positive for anti-HBc and anti-HBe, and 30 (90.9%) women had their hepatitis B viral load measured. Three (10.0%) had undetectable viral loads, 23 (76.7%) had low viral loads of < 2000 (IU/ml), 2 had moderate viral loads between 2000 and 200,000 (IU/ml) and one had a high viral load of 486,000 (IU/ml). CONCLUSION: Our study shows that the HBV prevalence in pregnant women is 1.49%, which is lower than what was reported earlier. Nevertheless, antenatal screening is still warranted, as there are vital interventions for the newborn and the mother.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Hepatitis B , Adulto , Estudios Transversales , ADN Viral , Femenino , Hepatitis B/diagnóstico , Hepatitis B/epidemiología , Anticuerpos contra la Hepatitis B , Antígenos e de la Hepatitis B , Virus de la Hepatitis B , Humanos , Inmunoglobulina M , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Masculino , Omán/epidemiología , Embarazo , Mujeres Embarazadas , Prevalencia
15.
J Infect Public Health ; 15(10): 1089-1096, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36116408

RESUMEN

BACKGROUND AND OBJECTIVE: The presence of carbapenemase enzymes among Enterobacterales is the main mechanism to reduce susceptibility to a wide range of antibiotics. Carbapenemase enzymes such as the Klebsiella pneumoniae carbapenemase (KPC) hydrolyse beta-lactam antibiotics group, which includes carbapenem, leads to fewer treatment options. We aim to describe the first report of carbapenem-resistant K. pneumoniae (CRKP) sequence type (ST) 11 harbouring KPC in Oman. MATERIAL AND METHODS: Five confirmed CRKP isolates were isolated from clinical samples during the period of January 2019 till December 2019. Strains were genotyped by pulse field gel electrophoresis (PFGE) for genetic relatedness. Whole genome sequencing (WGS) was performed to observe relationships with global strains using multilocus sequence typing (MLST). Antimicrobial genes, capsular loci-K-types, plasmids types and virulence genes were also identified using whole genome sequence data. RESULTS: All five CRKP were determined to have blaKPC-2 with or without blaOX-A48 and blaNDM-2. The molecular genotyping by PFGE showed 100% similarity among the five isolates. The MLST allelic profile analysis clonally clustered our strains with SL-258, CG-11 and ST11 mainly reported from South Asia. Further molecular characterization of the capsular K-locus and O-locus genes, revealed the strains to belong to KL-47 type and OL101 type respectively. The core genome typing suggests that our strains were clonally related to Chinese strains with less than five chromosomal nucleotides differences. CONCLUSION: Epidemiological and molecular analyses confirmed that these KPC-producing K. pneumoniae strains are from a single clone that caused multiple nosocomial infections in one health institution. This finding highlights the importance to sustain the surveillance and infection prevention efforts and to step up active screening to prevent the spread of nosocomial infection.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella , Humanos , Klebsiella pneumoniae , Tipificación de Secuencias Multilocus , Omán/epidemiología , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/tratamiento farmacológico , beta-Lactamasas/genética , beta-Lactamasas/uso terapéutico , Proteínas Bacterianas/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Genómica , Pruebas de Sensibilidad Microbiana
16.
PeerJ ; 10: e13645, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35919400

RESUMEN

Background: The Sultanate of Oman is country a low TB-incidence, with less than seven cases per 105 population detected in 2020. Recent years have witnessed a persistence in TB cases, with sustained incidence rate among expatriates and limited reduction among Omanis. This pattern suggests transmission from the migrant population. The present study examined the genetic profile and drug resistance-conferring mutations in Mycobacterium tuberculosis collected from Omanis and expatriates to recognise possible causes of disease transmission. Methods: We examined M. tuberculosis cultured positive samples, collected from Omanis (n = 1,344) and expatriates (n = 1,203) between 2009 and 2018. These isolates had a known in vitro susceptibility profile to first line anti-TB, Streptomycin (SM), Isoniazid (INH), Rifampicin (RIF), Ethambutol (EMB) and Pyrazinamide (PZA). The diversity of the isolates was assessed by spacer oligo-typing (spoligotyping). Drug resistance-conferring mutations resulted from full-length sequence of nine genes (katG, inhA, ahpc, rpoB, rpsL, rrs, embB, embC, pncA) and their phenotypic relationship were analysed. Results: In total, 341/2192 (13.4%), M. tuberculosis strains showed resistance to any drug, comprising mono-resistance (MR) (242, 71%), poly-resistance (PR) (40, 11.7%) and multi-drug resistance (MDR) (59, 17.3%). The overall rate of resistance among Omanis and expatriates was similar; however, MDR and PZAR were significantly higher among Omanis, while INHR was greater among expatriates. Mutations rpsL K43R and rpoB S450L were linked to Streptomycin (SMR) and Rifampicin resistance (RIFR) respectively. Whereas, katG S315T and inhA -C15T/G-17T were associated with Isoniazid resistance (INHR). The resistance patterns (mono-resistant, poly-resistant and MDR) and drug resistance-conferring mutations were found in different spoligo-lineages. rpsL K43R, katG S315T and rpoB S450L mutations were significantly higher in Beijing strains. Conclusions: Diverse drug resistant M. tuberculosis strains exist in Oman, with drug resistance-conferring mutations widespread in multiple spoligo-lineages, indicative of a large resistance reservoir. Beijing's M. tuberculosis lineage was associated with MDR, and multiple drug resistance-conferring mutations, favouring the hypothesis of migration as a possible source of resistant lineages in Oman.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Antituberculosos/farmacología , Mycobacterium tuberculosis/genética , Isoniazida/farmacología , Omán/epidemiología , Rifampin/farmacología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Estreptomicina/farmacología , Mutación/genética
17.
Pathogens ; 11(5)2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35631062

RESUMEN

Study aim. Effective Tuberculosis (TB) control measures in Oman have reduced the annual incidence of tuberculosis cases by 92% between 1981 and 2016. However, the current incidence remains above the program control target of <1 TB case per 100,000 population. This has been partly attributed to a high influx of migrants from countries with high TB burdens. The present study aimed to elucidate Mycobacterium tuberculosis infection dynamics among nationals and foreigners over a period of 10 years. Methods. The study examined TB cases reported between 2009 and 2018 and examined the spatial heterogeneity of TB cases and the distribution of M. tuberculosis genotypes defined by spoligotypes and MIRU-VNTR among Omanis and foreigners. Results. A total of 484 spoligoprofiles were detected among the examined isolates (n = 1295). These include 943 (72.8%) clustered and 352 (27.2%) unique isolates. Diverse M. tuberculosis lineages exist in all provinces in Oman, with most lineages shared between Omanis and foreigners. The most frequent spoligotypes were found to belong to EAI (318, 30.9%), CAS (310, 30.1%), T (154, 14.9%), and Beijing (88, 8.5%) lineages. However, the frequencies of these lineages differed between Omanis and foreigners. Of the clustered strains, 192 MTB isolates were further analysed via MIRU-VNTR. Each isolate exhibited a unique MIRU-VNTR profile, indicative of absence of ongoing transmission. Conclusions. TB incidence exhibits spatial heterogeneity across Oman, with high levels of diversity of M. tuberculosis lineages among Omanis and foreigners and sub-lineages shared between the two groups. However, MIRU-VNTR analysis ruled out ongoing transmission.

18.
East Mediterr Health J ; 28(12): 856-862, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36573565

RESUMEN

Background: Since 2007, national public health laboratories in the WHO Eastern Mediterranean Region (EMR) have participated in a regional external quality assessment scheme in bacteriology to improve testing proficiency. Aims: To assess laboratory performance in bacteriology in the EMR between 2011 and 2019 using the regional external quality assessment scheme. Methods: We analysed the accuracy of participant-reported data in bacterial identification, Gram stain microscopy, and antimicrobial susceptibility testing. For each category, we assessed the performance over time, the performance on multiple organisms, and whether a laboratory repeatedly failed to attain satisfactory results. Results: Between 2011 and 2019, 70% of laboratories achieved satisfactory performance for bacterial identification and antimicrobial susceptibility testing, and 85% performed satisfactory Gram stain microscopy. Testing did not improve on multiple organisms and results were consistently low for some pathogens and test categories. Twenty-nine percent of laboratories underperformed throughout the study period. Conclusion: The unchanged performance over time and underperformance of laboratories highlight the need for improvements in the regional external quality assessment scheme. Participating laboratories and WHO need to work more actively to strengthen the problem areas.


Asunto(s)
Antiinfecciosos , Bacteriología , Humanos , Laboratorios , Control de Calidad , Región Mediterránea , Garantía de la Calidad de Atención de Salud
19.
IJID Reg ; 1: 135-141, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35757821

RESUMEN

Objectives: To highlight the importance of molecular testing in characterizing extensively drug-resistant (XDR) Salmonella Typhi (S. Typhi), and linking it to the current outbreak in Sindh, Pakistan. Methods: Our study reports three travel-related typhoid fever cases caused by XDR S. Typhi that presented between January 2019 and August 2019. Antimicrobial susceptibility and genotyping with pulse-field gel electrophoresis (PFGE) were carried out. Whole-genome sequencing (WGS) was performed to characterize the genomic clonality in relation to the emerging outbreak of S. Typhi in Sindh, Pakistan, and to study the molecular resistance profiles. Results: Laboratory testing revealed resistance to all first-line antibiotics (i.e ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole), as well as to quinolones and third-generation cephalosporins, leading to a change in the patients' therapy to the use of carbapenems. Classical MLST (cMLST) revealed that the strains were of sequence type 1 (ST1) and the core genome sequence (cgWGS) analysis closely clustered our strains with internationally reported strains from Pakistan, India, and the UK. The strains were found to carry a bla CTX-15 gene-harbouring IncY plasmid, which encodes resistance to ceftriaxone. Conclusions: Our report alerts clinicians to the use of appropriate empirical treatments in such scenarios, and highlights the significance of the global spread of XDR S. Typhi.

20.
Saudi J Kidney Dis Transpl ; 32(2): 532-542, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35017349

RESUMEN

West Nile virus (WNV) infections are a mosquito-borne virus of the Flaviviridae family. The clinical feature of the virus varies between individuals from being asymptomatic in most of the cases to severe central nervous system disease manifested as meningitis, encephalitis, and paralysis. Diabetic nephropathy patient with microvascular and macrovascular complications, who received a kidney transplant a year ago on immunosuppressive therapy, presented with a three-day history of upper respiratory tract infection and fever. He lived in an endemic area of brucella infection. He underwent a thorough and full evaluation with various laboratory and radiological evaluations. The patient was started empirically on ceftriaxone and acyclovir for a presumptive diagnosis of herpes encephalitis and covering also Listeria with ampicillin. The patient did not improve with the initial management, so a T2-weighted magnetic resonance imaging of the brain executed that showed nonspecific hyper-intensity in the left frontal area suggestive of microangiopathic changes. WNV-neutralizing antibodies were positive with a high titer >1:640, whereas WNV RNA was not detected in the plasma sample. In the serum sample, WNV IgM and IgG were both positive. WNV IgM antibodies were detected with 6.55 and 5.97 antibody index and were done by a semiquantitative ELISA. Furthermore, WNV-neutralizing antibodies were positive as well as with a titer of 1:80. As there is no specific antiviral treatment available, the patient management was supportive; reduction in immunosuppressive agents and the use of IV IgG. This is the first reported case of one-year post renal transplant who developed WNV encephalitis and neuropathy with significant response to immunoglobulin after 18 days of infections.


Asunto(s)
Trasplante de Riñón , Fiebre del Nilo Occidental/diagnóstico , Virus del Nilo Occidental/aislamiento & purificación , Adulto , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales/sangre , Humanos , Huésped Inmunocomprometido , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Trasplante de Riñón/efectos adversos , Masculino , Fiebre del Nilo Occidental/sangre , Virus del Nilo Occidental/inmunología
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