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1.
Trop Med Infect Dis ; 8(8)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37624348

RESUMO

Dengue virus serotype 4 (DENV-4) has been the rarest circulating serotype in Malaysia, resulting in it being an understudied area. A recent observation from institutional surveillance data indicated a rapid increase in DENV-4-infected cases. The present study aimed to investigate the resurgence of DENV-4 in relation to the demographic, clinical and genomic profiles of 75 retrospective dengue samples. First, the demographic and clinical profiles obtained between 2017 and July 2022 were statistically assessed. Samples with good quality were subjected to full genome sequencing on the Illumina Next Seq 500 platform and the genome data were analysed for the presence of mutations. The effect of the mutations of interest was studied via an in silico computational approach using SWISS-MODEL and AlphaFold2 programs. The predominance of DENV-4 was discovered from 2021 to 2022, with a prevalence of 64.3% (n = 9/14) and 89.2% (n = 33/37), respectively. Two clades with a genetic divergence of 2.8% were observed within the dominant genotype IIa. The majority of DENV-4-infected patients presented with gastrointestinal symptoms, such as vomiting (46.7%), persistent diarrhoea (30.7%) and abdominal pain (13.3%). Two mutations, His50Tyr and Pro144Ser, located at the wing domain of the NS1 protein were discovered to be unique to the recently sequenced DENV-4.

2.
Biomedicines ; 11(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37371753

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been identified as the etiologic agent for the pneumonia outbreak that started in early December 2019 in Wuhan City, Hubei Province, China. To date, coronavirus disease (COVID-19) has caused almost 6 million deaths worldwide. The ability to propagate the virus into a customizable volume will enable better research on COVID-19 therapy, vaccine development, and many others. In the search for the most efficient replication host, we inoculated three (3) local SARS-CoV-2 isolates of different lineages (Clade L/Lineage B Wuhan, Clade GR/Lineage B.1.1.354, and Clade O/Lineage B.6.2) into various clinically important mammalian cell lines. The replication profile of these isolates was evaluated based on the formation of cytopathic effects (CPE), viral load (Ct value and plaque-forming unit (pfu)), as well as observation by electron microscopy (EM). Next-generation sequencing (NGS) was performed to examine the genomic stability of the propagated SARS-CoV-2 in these cell lines. Our study found that Vero E6 and Vero CCL-81 cell lines posed similar capacities in propagating the local isolates, with Vero CCL-81 demonstrating exceptional potency in conserving the genomic stability of the Lineage B Wuhan isolate. In addition, our study demonstrated the utility of Calu-3 cells as a replication host for SARS-CoV-2 without causing substantial cellular senescence. In conclusion, this study provides crucial information on the growth profile of Malaysian SARS-CoV-2 in various mammalian cell lines and thus will be a great source of reference for better isolation and propagation of the SARS-CoV-2 virus isolated in Malaysia.

3.
Emerg Microbes Infect ; 12(1): 2208678, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37101375

RESUMO

Prospective cohort study to investigate the potential exposure to the Middle East Respiratory Syndrome-Coronavirus (MERS-CoV) following Hajj pilgrims is still very limited. Here, we report the antibody seroconversion study results obtained from successive three years cohort studies (2016-2018) involving the Malaysian Hajj pilgrims returning from the Middle East. A cohort study of Hajj pilgrims from Malaysia enrolled 2,863 participants from 2016-2018, all of whom consented to provide paired blood samples for both pre- and post-Hajj travel to the Middle East. ELISAs and micro-neutralization assays were performed to detect the presence of MERS-CoV IgG antibodies. Sociodemographic data, symptoms experienced during Hajj, and history of exposure to camels or camel products were recorded using structured pre- and post-Hajj questionnaires. A 4-fold increase in anti-MERS-CoV IgG between paired pre-Hajj and post-Hajj serum samples in twelve participants was observed. None of the twelve ELISA-positive sera had detectable levels of virus-neutralizing antibodies. All reportedly had mild symptoms of respiratory symptoms at a certain point during the pilgrimage, implying mild or asymptomatic infections. No association between post-Hajj serum positivity and a history of exposure to camels or camel products was obtained. Findings from the study suggest that serologic conversion to MERS-CoV occurred in at least 0.6% of the Hajj pilgrims returning from the Middle East. Since all the seroconvertants had mild to no symptoms during the sampling period, it highlights the likelihood of occurrence of only low infectivity spillover infections among the Hajj pilgrims.


Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Animais , Camelus , Estudos Prospectivos , Estudos de Coortes , Soroconversão , Oriente Médio/epidemiologia , Viagem , Arábia Saudita/epidemiologia
4.
Int J Mol Sci ; 24(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37047115

RESUMO

The coronavirus disease 2019 (COVID-19) became a worldwide concern at the beginning of 2020 and has affected millions. Several previous studies revealed the impact of the imbalanced innate immune response on the progression of COVID-19 and its disease outcomes. High levels of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) and interleukins are produced readily by innate immune cells to fight Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) infections. Nonetheless, cytokine-mediated inflammatory events are also linked to detrimental lung injury and respiratory failure, which can result in deaths among COVID-19 patients. TNF-α is amongst the early cytokines produced to mediate proinflammatory responses and enhance immune cell infiltration in response to SARS-CoV-2 infections. In COVID-19, TNF-α-mediated inflammation can cause detrimental tissue damage and gradually promotes lung fibrosis, which later results in pneumonia, pulmonary edema, and acute respiratory distress syndrome. This review, therefore, aims to deliberate the immunomodulatory roles of TNF-α in promoting inflammation and its relation with COVID-19 morbidity and mortality. In addition, this review also proposes the potential of TNF-α as a biomarker for the prognosis of severe COVID-19 and its related complications and as a molecular target for anti-TNF-α therapy.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Fator de Necrose Tumoral alfa , Inibidores do Fator de Necrose Tumoral , Citocinas , Inflamação
5.
Arch Microbiol ; 205(2): 76, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36708390

RESUMO

Wastewater monitoring for SARS-CoV-2 has attracted considerable attention worldwide to complement the existing clinical-based surveillance system. In this study, we report our first successful attempt to prove the circulation of SARS-CoV-2 genes in Malaysian urban wastewater. A total of 18 wastewater samples were obtained from a regional sewage treatment plant that received municipal sewage between February 2021 and May 2021. Using the quantitative PCR assay targeting the E and RdRp genes of SARS-CoV-2, we confirmed that both genes were detected in the raw sewage, while no viral RNA was found in the treated sewage. We were also able to show that the trend of COVID-19 cases in Kuala Lumpur and Selangor was related to the changes in SARS-CoV-2 RNA levels in the wastewater samples. Overall, our study highlights that monitoring wastewater for SARS-CoV-2 should help local health professionals to obtain additional information on the rapid and silent circulation of infectious agents in communities at the regional level.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2/genética , Águas Residuárias , Esgotos , RNA Viral/genética , Malásia/epidemiologia , Monitoramento Ambiental
6.
BMJ Open ; 11(12): e055142, 2021 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-34952885

RESUMO

INTRODUCTION: To achieve the elimination of hepatitis C virus (HCV), substantial scale-up in access to testing and treatment is needed. This will require innovation and simplification of the care pathway, through decentralisation of testing and treatment to primary care settings and task-shifting to non-specialists. The objective of this study was to evaluate the feasibility and effectiveness of decentralisation of HCV testing and treatment using rapid diagnostic tests (RDTs) in primary healthcare clinics (PHCs) among high-risk populations, with referral of seropositive patients for confirmatory viral load testing and treatment. METHODS: This observational study was conducted between December 2018 and October 2019 at 25 PHCs in three regions in Malaysia. Each PHC was linked to one or more hospitals, for referral of seropositive participants for confirmatory testing and pretreatment evaluation. Treatment was provided in PHCs for non-cirrhotic patients and at hospitals for cirrhotic patients. RESULTS: During the study period, a total of 15 366 adults were screened at the 25 PHCs, using RDTs for HCV antibodies. Of the 2020 (13.2%) HCV antibody-positive participants, 1481/2020 (73.3%) had a confirmatory viral load test, 1241/1481 (83.8%) were HCV RNA-positive, 991/1241 (79.9%) completed pretreatment assessment, 632/991 (63.8%) initiated treatment, 518/632 (82.0%) completed treatment, 352/518 (68.0%) were eligible for a sustained virological response (SVR) cure assessment, 209/352 (59.4%) had an SVR cure assessment, and SVR was achieved in 202/209 (96.7%) patients. A significantly higher proportion of patients referred to PHCs initiated treatment compared with those who had treatment initiated at hospitals (71.0% vs 48.8%, p<0.001). CONCLUSIONS: This study demonstrated the effectiveness and feasibility of a simplified decentralised HCV testing and treatment model in primary healthcare settings, targeting high-risk groups in Malaysia. There were good outcomes across most steps of the cascade of care when treatment was provided at PHCs compared with hospitals.


Assuntos
Hepacivirus , Hepatite C , Adulto , Antivirais/uso terapêutico , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Humanos , Malásia , Atenção Primária à Saúde
7.
BMJ Open ; 11(8): e050901, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446498

RESUMO

INTRODUCTION: Middle East respiratory syndrome (MERS) is a viral respiratory infection caused by the MERS-CoV. MERS was first reported in the Kingdom of Saudi Arabia in 2012. Every year, the Hajj pilgrimage to Mecca attracts more than two million pilgrims from 184 countries, making it one of the largest annual religious mass gatherings (MGs) worldwide. MGs in confined areas with a high number of pilgrims' movements worldwide continues to elicit significant global public health concerns. MERCURIAL was designed by adopting a seroconversion surveillance approach to provide multiyear evidence of MG-associated MERS-CoV seroconversion among the Malaysian Hajj pilgrims. METHODS AND ANALYSIS: MERCURIAL is an ongoing multiyear prospective cohort study. Every year, for the next 5 years, a cohort of 1000 Hajj pilgrims was enrolled beginning in the 2016 Hajj pilgrimage season. Pre-Hajj and post-Hajj serum samples were obtained and serologically analysed for evidence of MERS-CoV seroconversion. Sociodemographic data, underlying medical conditions, symptoms experienced during Hajj pilgrimage, and exposure to camel and untreated camel products were recorded using structured pre-Hajj and post-Hajj questionnaires. The possible risk factors associated with the seroconversion data were analysed using univariate and multivariate logistic regression. The primary outcome of this study is to better enhance our understanding of the potential threat of MERS-CoV spreading through MG beyond the Middle East. ETHICS AND DISSEMINATION: This study has obtained ethical approval from the Medical Research and Ethics Committee (MREC), Ministry of Health Malaysia. Results from the study will be submitted for publication in peer-reviewed journals and presented in conferences and scientific meetings. TRIAL REGISTRATION NUMBER: NMRR-15-1640-25391.


Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Humanos , Islamismo , Oriente Médio/epidemiologia , Estudos Prospectivos , Arábia Saudita/epidemiologia , Viagem
8.
Viruses ; 13(5)2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925055

RESUMO

The COVID-19 pandemic has affected all individuals across the globe in some way. Despite large numbers of reported seroprevalence studies, there remains a limited understanding of how the magnitude and epitope utilization of the humoral immune response to SARS-CoV-2 viral anti-gens varies within populations following natural infection. Here, we designed a quantitative, multi-epitope protein microarray comprising various nucleocapsid protein structural motifs, including two structural domains and three intrinsically disordered regions. Quantitative data from the microarray provided complete differentiation between cases and pre-pandemic controls (100% sensitivity and specificity) in a case-control cohort (n = 100). We then assessed the influence of disease severity, age, and ethnicity on the strength and breadth of the humoral response in a multi-ethnic cohort (n = 138). As expected, patients with severe disease showed significantly higher antibody titers and interestingly also had significantly broader epitope coverage. A significant increase in antibody titer and epitope coverage was observed with increasing age, in both mild and severe disease, which is promising for vaccine efficacy in older individuals. Additionally, we observed significant differences in the breadth and strength of the humoral immune response in relation to ethnicity, which may reflect differences in genetic and lifestyle factors. Furthermore, our data enabled localization of the immuno-dominant epitope to the C-terminal structural domain of the viral nucleocapsid protein in two independent cohorts. Overall, we have designed, validated, and tested an advanced serological assay that enables accurate quantitation of the humoral response post natural infection and that has revealed unexpected differences in the magnitude and epitope utilization within a population.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Antígenos Virais/imunologia , COVID-19/epidemiologia , COVID-19/virologia , Teste Sorológico para COVID-19 , Estudos de Casos e Controles , Estudos de Coortes , Epitopos , Etnicidade , Feminino , Humanos , Imunidade Humoral , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas do Nucleocapsídeo/genética , Proteínas do Nucleocapsídeo/imunologia , Pandemias , SARS-CoV-2/genética , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Índice de Gravidade de Doença , Adulto Jovem
9.
J Med Virol ; 93(4): 2461-2466, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33393672

RESUMO

An optimal clinical specimen for accurate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by minimizing the usage of consumables and reduce hazard exposure to healthcare workers is an urgent priority. The diagnostic performance of SARS-CoV-2 detection between healthcare worker-collected nasopharyngeal and oropharyngeal (NP + OP) swabs and patient performed self-collected random saliva was assessed. Paired NP + OP swabs and random saliva were collected and processed within 48 h of specimen collection from two cohort studies which recruited 562 asymptomatic adult candidates. Real-time reverse-transcription polymerase chain reaction targeting Open reading frame 1a (ORF1a) and nucleocapsid (N) genes was performed and the results were compared. Overall, 65 of 562 (28.1%) candidates tested positive for COVID-19 based on random saliva, NP + OP swabs, or both testing techniques. The detection rate of SARS-CoV-2 was higher in random saliva compared to NP + OP testing (92.3%; 60/65 vs. 73.8%; 48/65; p < .05). The estimated sensitivity and specificity of random saliva were higher than NP + OP swabs (95.0; 99.9 vs. 72.2; 99.4). The Ct  values of ORF1a and N genes were significantly lower in random saliva compared to NP + OP swabs specimens. Our findings demonstrate that random saliva is an alternative diagnostic specimen for the detection of SARS-CoV-2. Self-collected random oropharyngeal saliva is a valuable specimen that provides accurate SARS-CoV-2 surveillance testing of a community.


Assuntos
Teste para COVID-19/métodos , COVID-19/diagnóstico , Orofaringe/virologia , SARS-CoV-2/isolamento & purificação , Saliva/virologia , Adulto , COVID-19/virologia , Técnicas de Laboratório Clínico/métodos , Estudos de Coortes , Estudos Transversais , Feminino , Pessoal de Saúde , Humanos , Masculino , Nasofaringe/virologia , Reação em Cadeia da Polimerase em Tempo Real , Manejo de Espécimes/métodos
10.
Clin Infect Dis ; 72(9): e352-e356, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32761244

RESUMO

BACKGROUND: The ideal severe acute respiratory syndrome coronavirus 2 (SARs-CoV-2) testing method would be accurate and also be patient-performed to reduce exposure to healthcare workers. The aim of this study was to compare patient-performed testing based on a morning saliva sample with the current standard testing method, healthcare worker-collected sampling via a nasopharyngeal swab (NPS). METHODS: This was a prospective single center study which recruited 217 asymptomatic adult male participants in a coronavirus disease 2019 (COVID-19) quarantine center who had tested positive for SARS-CoV-2 8-10 days prior to isolation. Paired NPS and saliva specimens were collected and processed within 5 hours of sample collection. Real time reverse transcription polymerase chain reaction (RT-PCR) targeting Envelope (E) and RNA-dependent RNA polymerase (RdRp) genes was performed and the results were compared. RESULTS: Overall, 160 of the 217 (74%) participants tested positive for COVID-19 based on saliva, NPS, or both testing methods. The detection rate for SARS-CoV-2 was higher in saliva compared to NPS testing (93.1%, 149/160 vs 52.5%, 84/160, P < .001). The concordance between the 2 tests was 45.6% (virus was detected in both saliva and NPS in 73/160), whereas 47.5% were discordant (87/160 tested positive for 1 whereas negative for the other). The cycle threshold (Ct) values for E and RdRp genes were significantly lower in saliva specimens compared to NP swab specimens. CONCLUSIONS: Our findings demonstrate that saliva is a better alternative specimen for detection of SARS-CoV-2. Taking into consideration, the simplicity of specimen collection, shortage of PPE and the transmissibility of the virus, saliva could enable self-collection for an accurate SARS-CoV-2 surveillance testing.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Humanos , Masculino , Nasofaringe , Estudos Prospectivos , Saliva , Manejo de Espécimes
11.
Sci Rep ; 10(1): 21009, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33273475

RESUMO

Malaysia is a country with an intermediate endemicity for hepatitis B. As the country moves toward hepatitis B and C elimination, population-based estimates are necessary to understand the burden of hepatitis B and C for evidence-based policy-making. Hence, this study aims to estimate the prevalence of hepatitis B and C in Malaysia. A total of 1458 participants were randomly selected from The Malaysian Cohort (TMC) aged 35 to 70 years between 2006 and 2012. All blood samples were tested for hepatitis B and C markers including hepatitis B surface antigen (HBsAg), anti-hepatitis B core antibody (anti-HBc), antibodies against hepatitis C virus (anti-HCV). Those reactive for hepatitis C were further tested for HCV RNA genotyping. The sociodemographic characteristics and comorbidities were used to evaluate their associated risk factors. Descriptive analysis and multivariable analysis were done using Stata 14. From the samples tested, 4% were positive for HBsAg (95% CI 2.7-4.7), 20% were positive for anti-HBc (95% CI 17.6-21.9) and 0.3% were positive for anti-HCV (95% CI 0.1-0.7). Two of the five participants who were reactive for anti-HCV had the HCV genotype 1a and 3a. The seroprevalence of HBV and HCV infection in Malaysia is low and intermediate, respectively. This population-based study could facilitate the planning and evaluation of the hepatitis B and C control program in Malaysia.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Adulto , Idoso , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Testes Sorológicos/estatística & dados numéricos , Fatores Socioeconômicos
12.
J Viral Hepat ; 27(6): 638-643, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31997563

RESUMO

Approximately 2.5% of the Malaysian population is currently living with hepatitis C virus (HCV) infection. Yet, the public awareness of the disease is limited and under-screening remains a major challenge. With the support of international non-for-profit organizations, the Ministry of Health in Malaysia recently launched a one-week nationwide hepatitis C screening campaign in conjunction with the World Hepatitis Day. For the first time, the rapid diagnostic test (RDT) for HCV screening was introduced in public health institutions. This campaign involved 49 hospitals and 38 health clinics across the country, targeting the adult general population with unknown HCV infection status. Of the 11 382 participants undergoing the RDT, 1.9% were found to be positive for hepatitis C antibody (anti-HCV) and were referred to on-site medical departments or nearby hospitals for confirmatory testing and treatment. Men, the Malay ethnic group, intranasal and injection drug users and ex-prisoners were shown to have higher odds of being positive for anti-HCV. In addition to serving as a model to educate the general population about the disease, this campaign demonstrates the feasibility of decentralizing HCV screening, particularly by promoting the use of RDT, and linking the HCV-infected patients to care in Malaysia.


Assuntos
Hepatite C , Programas de Rastreamento , Adulto , Usuários de Drogas , Etnicidade , Feminino , Hepacivirus , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C , Humanos , Malásia/epidemiologia , Masculino , Prisioneiros
13.
Asian Pac J Trop Med ; 10(1): 75-78, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28107870

RESUMO

OBJECTIVE: To determine drug resistance mutations and the HIV-1 subtypes among antiretroviral treatment naive HIV-1 patients in Peninsular Malaysia. METHODS: A total of 45 samples from four hospitals that provide HIV viral load services were subjected to the amplification of the protease and two third of reverse transcriptase regions of the pol gene by RT-PCR and Sanger sequencing. Drug resistance mutation (DRM) interpretation reports the presence of mutations related to protease inhibitors (PIs), Nucleoside reverse-transcriptase inhibitors (NRTI) and Non-nucleoside reverse-transcriptase inhibitors (NNRTI) based on analysis using Stanford HIV database program. RESULTS: DRMs were identified in 35% of patients, among which 46.7% of them showed minor resistance to protease inhibitor with A71V and L10l were the commonest DRMs detected. About 21.4% and 50.0% of patients had mutations to NRTIs and NNRTIs, respectively. CRF01_AE was found to be the predominant HIV-1 subtype. CONCLUSIONS: These findings have served as an initial crucial data in determining the prevalence of transmitted HIV-1 drug resistance for the country. However, more samples from various parts of the country need to be accumulated and analyzed to provide overall HIV-1 drug resistance in the country.

14.
Asian Pac J Trop Med ; 9(2): 201-3, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26919957

RESUMO

An efficient public health preparedness and response plan for infectious disease management is important in recent times when emerging and exotic diseases that hitherto were not common have surfaced in countries with potential to spread outside borders. Stewardship from a reference laboratory is important to take the lead for the laboratory network, to proactively set up disease surveillance, provide referral diagnostic services, on-going training and mentorship and to ensure coordination of an effective laboratory response. In Malaysia, the Institute for Medical Research has provided the stewardship for the Ministry of Health's laboratory network that comprises of hospital pathology, public health and university laboratories. In this paper we share our experiences in recent infectious disease outbreak investigations as a reference laboratory within the Ministry of Health infectious disease surveillance network.

15.
Hepat Mon ; 15(10): e31490, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26587040

RESUMO

BACKGROUND: Precore stop codon (G1896A) mutation is one of the commonest mutations found in patients with chronic hepatitis B. However, over the years, this mutation was not reported much in Malaysia. OBJECTIVES: We therefore investigated the presence of G1896A mutation in Malaysian population and its association with HBeAg status, clinical stage, hepatitis B virus (HBV) genotype and e-seroconversion rate. PATIENTS AND METHODS: Serum samples from 93 patients confirmed as hepatitis B carriers were collected for molecular assay. The whole genome of HBV was amplified by polymerase chain reaction and directly sequenced. The precore and basal core promoter regions were analyzed for presence of mutations. RESULTS: The most commonly observed mutation in the precore region was C1858T with 64.5% prevalence. The precore mutation of interest (G1896A) was identified in 25.8% of isolates. The basal core promoter mutations detected were A1762T-G1764A (26.9%), C1653T (8.6%), A1752G (10.8%) and C1766T (2.2%). No significant association was observed between G1896A mutation and HBeAg-negativity. Nonetheless, G1896A was highly prevalent among HBV genotype B. Clinical association revealed that subjects with G1896A mutations were mainly detected in asymptomatic chronic hepatitis B (58.3%) and liver cirrhosis (41.7%). One subject was diagnosed with fulminant hepatitis (4.2%) and 8.3% had hepatocellular carcinoma (HCC). CONCLUSIONS: Our data suggested an intermediate prevalence of G1896A mutation among Malaysian hepatitis B carriers. The stop codon mutation has a significant association with genotype B and patients with chronic hepatitis B and liver cirrhosis.

16.
Hepat Mon ; 14(1): e13173, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24497877

RESUMO

BACKGROUND: Mutations in the polymerase (P) gene of hepatitis B virus are often associated with drug resistance. The pattern of mutations varies geographically, thus giving rise to genotypes diversity. OBJECTIVES: This study was carried out to detect mutations in P gene of hepatitis B virus isolated from Malaysian HBV carriers. MATERIALS AND METHODS: A total of 58 sera samples were analyzed by PCR and sequencing, of which the P gene of isolated HBV was successfully amplified and sequenced from 40 samples. RESULTS: Genotyping of these samples revealed that the predominant genotype was genotype C (22/40, 55.0%), followed by genotype B (17/40, 42.5%), and only 1 sample showed genotype D (2.5%). A number of significant drug resistant mutations were found in five patients including S202I, N236T, M250L, L180M/V, M204I, A181T, T184G, M250V, and V173L. Of these, L180M/V and M204I were most frequently detected (80%) and associated with lamivudine in combination with emtricitabine and telbivudine drug resistance. Association with age, sex, and clinical symptoms revealed that these patients were all male, mid to elderly age and almost all hadcirrhotic liver disease. CONCLUSIONS: Detection and surveillance of the significant sites of mutations in HBV is crucial for clinicians to decide on the choice of antiviral treatment and further management of hepatitis B carriers.

17.
Hepat Mon ; 14(12): e22565, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25737728

RESUMO

BACKGROUND: The S gene region of the hepatitis B virus (HBV) codes for surface antigen (HBs Ag) and is responsible for classification of HBV strains. OBJECTIVES: The current study aimed to identify important mutations in the S gene in Hepatitis B virus (HBV) isolated from Malaysian HBV carriers. MATERIALS AND METHODS: Isolated HBV DNAs were subjected for PCR amplification and sequencing of HBV full genome. RESULTS: A total of 76 HBV full genome and 17 partial genome sequences were obtained from the 93 sequenced sera samples Genotyping of the full genome sequences by HEPSEQ software revealed a distribution of 49.46%, 48.39% and 2.15% of genotypes C, B, and D, respectively; whereas phylogenetic and jumping profile Hidden Markov Model (jpHMM) analysis identified six (7.89%) recombinant B/C strains. The distribution of sub-genotypes were B2 (78.79%) and B3 (21.21%) for genotype B, sub genotype D2 (100%) for genotype D and sub genotype C1 (75.76%), C2 (15.15%), C3 (6.06%) and C5 (3.13%) for genotype C. Mutation analysis in the S gene demonstrated two significant mutations which were W182 stop codon and deletion at open reading frame (ORF) of pre-S1 with the frequency occurrence of 2.2% (2/93) and 5.4% (5/93), respectively. The two patients with W182 stop codon were both male, infected with HBV genotype C and one showed progression of liver disease to hepatocellular carcinoma (HCC). CONCLUSIONS: Association with sex, genotype and clinical symptoms revealed that the pre-S1 ORF deletion occurred in 40% , 40%,and 20% of genotypes B,C, and D respectively, and 80% of the female population, of which all but one were diagnosed with chronic hepatitis B. Additionally, several mutations were found in the BCP region with the following incidence rate; C1653 T (8.6%), A1752 G (10.8%),1762 AGG--TGA 1764 (26.9%), C1766T(2.2%),T1768 A (10.8%), C1858 T (64.5%), G1896 A (25.8%).

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