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1.
Int J Infect Dis ; 139: 109-117, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37984763

RESUMEN

OBJECTIVES: SARS-CoV-2 transmission and epidemic potential is related to the population's immunity levels. As such, assessing different regions' preexisting immune responses to SARS-CoV-2 is important to understand the transmission potential of emerging SARS-CoV-2 variants. DESIGN: In 975 serum samples from Vietnam (2014 to 2019), anti-SARS-CoV-2 Immunoglobulin G levels were determined by enzyme-linked immunosorbent assay. Plaque reduction neutralization test (PRNT) was performed using Wuhan strain and variants of concern (VOCs). Cross-reactivity was confirmed by analyzing B-cell receptor (BCR) repertoire sequences and identifying BCR repertoire sequences-derived T-cell epitopes. RESULTS: Overall, 20.9% (n = 76/364) and 9.2% (n = 7) demonstrated SARS-CoV-2 neutralizing activity (PRNT50) against the Wuhan and Alpha strain, respectively. Neutralizing activity against Beta, Gamma, and Delta strains was absent (PRNT50<5) in all samples. Cross-reactive epitopes against SARS-CoV-2 and other coronavirus spike proteins were detected in the N-terminal domain, S2, and receptor-binding domain regions. CONCLUSIONS: Following BCR and major histocompatibility complex analysis, T-cell receptor-recognized epitope motif (TREM) among pathogenic coronaviruses and coronaviruses spike proteins were the top TREM peptide, suggesting that pre-existing immunity against SARS-CoV-2 in Vietnam was due to exposure to common cold coronaviruses. With limited immunity against emerging VOCs, further monitoring, and control of the epidemic, along with COVID-19 vaccine programs against VOCs, are necessary.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Vacunas contra la COVID-19 , Vietnam/epidemiología , Pandemias , Estaciones del Año , Glicoproteína de la Espiga del Coronavirus/genética , Epítopos , Anticuerpos Neutralizantes , Anticuerpos Antivirales
2.
Viruses ; 15(10)2023 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-37896842

RESUMEN

Chikungunya fever is an acute febrile illness caused by the chikungunya virus (CHIKV), which is transmitted by Aedes mosquitoes. Since 1965, only a few studies with limited scope have been conducted on CHIKV in Vietnam. Thus, this study aimed to determine the seroprevalence and molecular epidemiology of CHIKV infection among febrile patients in Vietnam from 2017 to 2019. A total of 1063 serum samples from 31 provinces were collected and tested for anti-CHIKV IgM and IgG ELISA. The 50% focus reduction neutralization test (FRNT50) was used to confirm CHIKV-neutralizing antibodies. Quantitative real-time RT-PCR (RT-qPCR) was performed to confirm the presence of the CHIKV genome. The results showed that 15.9% (169/1063) of the patients had anti-CHIKV IgM antibodies, 20.1% (214/1063) had anti-CHIKV IgG antibodies, 10.4% (111/1063) had CHIKV-neutralizing antibodies, and 27.7% (130/469) of the samples were positive in RT-qPCR analysis. The E1 CHIKV genome sequences were detected among the positive RT-qPCR samples. Our identified sequences belonged to the East/Central/South/African (ECSA) genotype, which has been prevalent in Vietnam previously, suggesting CHIKV has been maintained and is endemic in Vietnam. This study demonstrates a high prevalence of CHIKV infection in Vietnam and calls for an annual surveillance program to understand its impact.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Animales , Humanos , Epidemiología Molecular , Estudios Seroepidemiológicos , Vietnam/epidemiología , Brotes de Enfermedades , Virus Chikungunya/genética , Anticuerpos Antivirales , Inmunoglobulina M , Inmunoglobulina G , Fiebre/epidemiología , Anticuerpos Neutralizantes/genética
3.
PLoS One ; 18(9): e0290235, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37656689

RESUMEN

The impact of direct-acting antivirals (DAA) therapy on lipid and glucose metabolism and kidney function in patients with hepatitis C virus (HCV) infection, along with its side effects on blood cells, remains controversial. Therefore, we conducted a study that enrolled 280 patients with HCV infection who achieved sustained virologic response after treatment with DAA therapy without ribavirin to evaluate the metabolic changes, renal function, and anemia risk based on real-world data. This study was an observational prospective study with a follow-up period of 12 weeks after the initiation of DAA therapy. Data on biochemical tests, renal function, blood counts, viral load, and host genomics were recorded before treatment and after 12 weeks of treatment with DAAs. DAA therapy reduced fibrosis-4 scores and improved liver function, with significant reductions in aspartate transaminase, alanine aminotransferase, and total bilirubin levels. However, DAA therapy slightly increased uric acid, cholesterol, and low-density lipoprotein cholesterol levels. It significantly reduced fasting blood glucose levels and hemoglobin A1C index (HbA1C) in the study group, while hemoglobin (Hb) and hematocrit (HCT) concentrations decreased significantly (4.78 ± 21.79 g/L and 0.09% ± 0.11%, respectively). The estimated glomerular filtration rate (eGFR) decreased by 12.89 ± 39.04 mL/min/1.73m2. Most variations were not related to the genotype, except for Hb, HCT, and HbA1C. Anemia incidence increased from 23.58% before treatment to 30.72% after treatment. Patients with HCV-1 genotype had a higher rate of anemia than did patients with genotype 6 (36.23% vs. 24.62%). Multivariate analysis showed that the risk of anemia was related to female sex, cirrhosis status, fibrosis-4 score, pretreatment eGFR, and pretreatment Hb level. The results of our study can provide helpful information to clinicians for the prognosis and treatment of HCV infection.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Humanos , Femenino , Antivirales/uso terapéutico , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Estudios Prospectivos , Hemoglobina Glucada , Hepacivirus/genética
4.
Biomed Res Int ; 2022: 6054677, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572735

RESUMEN

Introduction: Direct-acting antivirals (DAAs) have significantly improved the efficacy and tolerability of the treatment of hepatitis C virus (HCV). However, studies conducted on actual patients with the aim of predicting the risk associated with treatment failure are lacking. Methods: Our study enrolled 334 new HCV patients and assessed the effectiveness of treatment and predicted the risk of failure to achieve sustained virological response (SVR) by developing a multiple logistic model. Our study compared the variables between the two groups, those who did (group 0, n = 239) and did not achieve SVR (group 1, n = 95). Results: The cure rate of HCV at 12th week in our study was 71.56%. We found that advanced cirrhosis, HCV genotype, HBV coinfection, rapid virological response (RVR), fibrosis index (FIB-4) score, serum levels of AST, ALP, hemoglobin, and viral load before treatment were prognostic factors associated with rate of failure to achieve SVR at week 12 of DAA therapy. In the multiple logistic model, eight significant predictors including advanced cirrhosis status, HCV genotype, RVR, AST/ALP levels, FIB-4 score, and viral load before treatment predicted the risk of failure with excellent model performance (area under the receiver operating characteristic curve (AUCROC) [95% CI] =0.986 (0.971-0.999)). RVR and advanced cirrhosis were the two strongest predictors with odd ratios (95% CI) =9.72 (2.8, 39.28) and 51.54 (6.39, 139.82), respectively. Conclusion: The multiple logistic regression model included significant factors to estimate the probability of failure to achieve SVR, which could improve HCV treatment strategy.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Antivirales , Genotipo , Hepacivirus/genética , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Humanos , Interferón-alfa/genética , Cirrosis Hepática/complicaciones , Polietilenglicoles/uso terapéutico , Estudios Prospectivos , Ribavirina/uso terapéutico , Factores de Riesgo , Resultado del Tratamiento
5.
Vector Borne Zoonotic Dis ; 22(2): 159-161, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35099293

RESUMEN

Trypanosoma lewisi is a worldwide nonpathogenic parasite that is exclusively found in rats. In general, T. lewisi infection in humans is an opportunistic infection from rats to humans through fleas. However, recently, infection with T. lewisi in humans, including a fatal case, has been reported. Notably, rats living close to a human settlement showed a higher prevalence of infection with T. lewisi than those living in other places. It is possible that the urbanization is associated with the prevalence of T. lewisi in rats and enhances the risk of T. lewisi transmission to humans through fleas. In this study, a total of 88 rats were captured from hospitals, markets, and a cargo station, of which 81 were identified as Rattus norvegicus and 7 as Rattus rattus in Hanoi, the urbanizing city of Vietnam. Of these, 55 rats (62.5%) harbored T. lewisi, of which 52 were R. norvegicus and 3 were R. rattus.


Asunto(s)
Ratas/parasitología , Trypanosoma lewisi , Tripanosomiasis , Animales , ADN Protozoario/genética , Humanos , Enfermedades de los Roedores/epidemiología , Enfermedades de los Roedores/parasitología , Enfermedades de los Roedores/transmisión , Siphonaptera/parasitología , Trypanosoma lewisi/genética , Tripanosomiasis/epidemiología , Tripanosomiasis/parasitología , Tripanosomiasis/transmisión , Tripanosomiasis/veterinaria , Vietnam/epidemiología , Zoonosis
6.
Trop Med Health ; 50(1): 3, 2022 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-34983690

RESUMEN

BACKGROUND: Dengue virus (DENV) is a member of insect vector-borne viruses, and it causes dengue fever. Southeast Asia is the epi-center of dengue fever in the world. The characterization of the virus is essential to identify the transmission and evolution of DENV. OBJECTIVES: In 2017, there was an outbreak of Dengue virus type 1 (DENV1) in northern Vietnam and the neighboring countries. To identify the genetic character of the outbreak virus in the area, we conducted whole-genome sequencing analysis on the samples positive for the DENV1 along with real-time PCR. STUDY DESIGN: In total, 1026 blood samples were collected from patients with suspected dengue fever in Ha Nam and Hai Duong province, nearby areas of the capital of Vietnam. After screening by real-time PCR, 40 of DENV1 positive samples were subjected to whole-genome sequencing, and 28 complete coding sequences were obtained. RESULTS: All 28 sequences were genotype I of DENV1, which is dominant in the southeast and East Asian countries. The phylogenetic analysis of the E region showed that they fell into a single cluster with the reported sequences from Vietnam between 2009 and 2016, in which the isolates from other countries are very rare. Our results suggested that the 2017 outbreak in the area was caused by locally circulating viruses.

7.
Pathogens ; 10(12)2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34959513

RESUMEN

The RT-qPCR method remains the gold standard and first-line diagnostic method for the detection of SARS-CoV-2 and flaviviruses, especially in the early stage of viral infection. Rapid and accurate viral detection is a starting point in the containment of the COVID-19 pandemic and flavivirus outbreaks. However, the shortage of diagnostic reagents and supplies, especially in resource-limited countries that experience co-circulation of SARS-CoV-2 and flaviviruses, are limitations that may result in lesser availability of RT-qPCR-based diagnostic tests. In this study, the utility of RNA-free extraction methods was assessed for the direct detection of SARS-CoV-2 and DENV-2 in heat-inactivated or chemical-inactivated samples. The findings demonstrate that direct real-time RT-qPCR is a feasible option in comparison to conventional real-time RT-qPCR based on viral genome extraction-based methods. The utility of heat-inactivation and direct real-time RT-qPCR for SARS-CoV-2, DENV-2 viral RNA detection was demonstrated by using clinical samples of SARS-CoV-2 and DENV-2 and spiked cell culture samples of SARS-CoV-2 and DENV-2. This study provides a simple alternative workflow for flavivirus and SARS-CoV-2 detection that includes heat inactivation and viral RNA extraction-free protocols, with aims to reduce the risk of exposure during processing of SARS-CoV-2 biological specimens and to overcome the supply-chain bottleneck, particularly in resource limited settings with flavivirus co-circulation.

8.
Ann Vasc Dis ; 14(3): 231-235, 2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34707744

RESUMEN

Objective: This study aims to describe the angiographic imaging characteristics of superficial venous malformations and evaluate the treatment effectiveness of digital subtraction angiography (DSA)-guided foam sclerotherapy with polidocanol. Materials and Methods: This prospective study was conducted in 18 patients with venous malformation treated by DSA-guided sclerotherapy. Treatment outcomes were evaluated based on pain improvement and reduction in lesion size on magnetic resonance imaging (MRI) 6-months posttreatment. Results: A total 21 lesions and 46 sclerotherapy sessions were analyzed. MRI findings presented 8/21 lesions (38.1%) with excellent response, 9/21 (42.9%) with good response, and 3/21 (14.3%) with average response, while one patient (4.8%) showed no response. All patients experienced pain. A significant reduction (p<0.01) was observed in the pre- to posttreatment pain score (5.45 and 0.64, respectively). Over a follow-up period of 1-4 years, three out of four patients (75%) in the retrospective cohort experienced recurrence; one patient had an increased lesion size and pain score, while the other two patients only showed an increased lesion size. No severe complications were seen. Conclusion: DSA-guided sclerotherapy with polidocanol is a safe and effective procedure for reducing lesion size and pain in symptomatic patients with superficial venous malformations.

9.
Artículo en Inglés | MEDLINE | ID: mdl-34574767

RESUMEN

Infectivity and neutralizing antibody titers of flavivirus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are frequently measured using the conventional plaque assay. While the assay is useful in the determination of infectivity, conventional plaque assays generally possess lower sensitivity and are time-consuming compared to nucleic acid amplification tests. In this study, a microcrystalline cellulose (MCC), Avicel, was evaluated as an alternative to the conventional virus overlay medium, methylcellulose, for a plaque assay. The plaque assay was performed using dengue and COVID-19 clinical samples and laboratory-established flavivirus and SARS-CoV-2 strains. In virus titration of clinical samples, the plaques were significantly larger, and the virus titers were higher when Avicel MCC-containing overlay medium was used than with conventional methylcellulose overlay medium. In addition, for some clinical samples and laboratory virus strains, infectious particles were detected as plaques in the Avicel MCC-containing medium, but not in the conventional methylcellulose medium. The results suggest that the viremia titer determined using the new overlay medium containing Avicel MCC may better reflect the innate infectious and plaque-forming capabilities of clinical samples and better reflect virus infectivity.


Asunto(s)
COVID-19 , Flavivirus , Humanos , SARS-CoV-2 , Viremia , Esparcimiento de Virus
10.
Elife ; 102021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34342576

RESUMEN

The evolution of influenza viruses is fundamentally shaped by within-host processes. However, the within-host evolutionary dynamics of influenza viruses remain incompletely understood, in part because most studies have focused on infections in healthy adults based on single timepoint data. Here, we analyzed the within-host evolution of 82 longitudinally sampled individuals, mostly young children, infected with A/H1N1pdm09 or A/H3N2 viruses between 2007 and 2009. For A/H1N1pdm09 infections during the 2009 pandemic, nonsynonymous minority variants were more prevalent than synonymous ones. For A/H3N2 viruses in young children, early infection was dominated by purifying selection. As these infections progressed, nonsynonymous variants typically increased in frequency even when within-host virus titers decreased. Unlike the short-lived infections of adults where de novo within-host variants are rare, longer infections in young children allow for the maintenance of virus diversity via mutation-selection balance creating potentially important opportunities for within-host virus evolution.


Asunto(s)
Evolución Molecular , Virus de la Influenza A/genética , Gripe Humana/epidemiología , Pandemias , Adolescente , Niño , Preescolar , Humanos , Gripe Humana/virología , Estaciones del Año , Vietnam/epidemiología , Adulto Joven
11.
Nat Commun ; 12(1): 2654, 2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33976181

RESUMEN

Most anti-influenza drugs currently used, such as oseltamivir and zanamivir, inhibit the enzymatic activity of neuraminidase. However, neuraminidase inhibitor-resistant viruses have already been identified from various influenza virus isolates. Here, we report the development of a class of macrocyclic peptides that bind the influenza viral envelope protein hemagglutinin, named iHA. Of 28 iHAs examined, iHA-24 and iHA-100 have inhibitory effects on the in vitro replication of a wide range of Group 1 influenza viruses. In particular, iHA-100 bifunctionally inhibits hemagglutinin-mediated adsorption and membrane fusion through binding to the stalk domain of hemagglutinin. Moreover, iHA-100 shows powerful efficacy in inhibiting the growth of highly pathogenic influenza viruses and preventing severe pneumonia at later stages of infection in mouse and non-human primate cynomolgus macaque models. This study shows the potential for developing cyclic peptides that can be produced more efficiently than antibodies and have multiple functions as next-generation, mid-sized biomolecules.


Asunto(s)
Antivirales/farmacología , Modelos Animales de Enfermedad , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Péptidos/farmacología , Neumonía/prevención & control , Animales , Antivirales/química , Perros , Femenino , Células HEK293 , Humanos , Subtipo H1N1 del Virus de la Influenza A/metabolismo , Macaca fascicularis , Células de Riñón Canino Madin Darby , Ratones Endogámicos BALB C , Estructura Molecular , Péptidos/química , Replicación Viral/efectos de los fármacos
12.
Langmuir ; 36(43): 13001-13011, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33090796

RESUMEN

The present study aims to investigate the adsorption of synthesized poly(2-acrylamide-2-methylpropane sulfonic acid) (PAMPs) onto alumina nanoparticles and their application in the removal of ciprofloxacin (CFX) antibiotic from a water environment. The PAMPs were successfully synthesized and characterized by nuclear magnetic resonance and gel-permeation chromatography methods. The number- and weight-average molecular weights of PAMPs were 6.76 × 105 and 7.28 × 106 g/mol, respectively. The charge reversal of nanoalumina after PAMPs modification from positive to -37.5 mV was determined by ζ-potential measurement, while the appearance of C ═ O and N-H functional groups in PAMPs observed by Fourier-transform infrared spectroscopy confirmed them as the main indicators for adsorption of PAMPs onto a nanoalumina surface. The maximum adsorption capacity of PAMPs onto nanoalumina in 100 mg/L KCl was about 10 mg/g. The adsorption isotherms were fitted well by a two-step adsorption model. Application of PAMPs-modified nanoalumina (PAMNA) in CFX removal was also thoroughly studied. The optimum conditions for CFX removal using PAMNA were found to be pH 6, 10 mM NaCl, contact time 90 min, and adsorption dosage 5 mg/mL. The CFX adsorption isotherms and kinetics were in accordance with the two-step and pseudo-second-order models, respectively. The application for CFX removal in actual hospital wastewater was greater than 80%. The results of this study demonstrate that PAMNA is a new and promising material for antibiotic removal from wastewater.

13.
Int J Mol Sci ; 21(15)2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-32718089

RESUMEN

Olean-12-en-27-oic acids possess a variety of pharmacological effects. However, their effects and underlying mechanisms on osteoclastogenesis remain unclear. This study aimed to investigate the anti-osteoclastogenic effects of five olean-12-en-27-oic acid derivatives including 3α,23-isopropylidenedioxyolean-12-en-27-oic acid (AR-1), 3-oxoolean-12-en-27-oic acid (AR-2), 3α-hydroxyolean-12-en-27-oic acid (AR-3), 23-hydroxy-3-oxoolean-12-en-27-oic acid (AR-4), and aceriphyllic acid A (AR-5). Among the five olean-12-en-27-oic acid derivatives, 3-hydroxyolean-12-en-27-oic acid derivatives, AR-3 and AR-5, significantly inhibited receptor activator of nuclear factor-κB ligand (RANKL)-induced mature osteoclast formation by reducing the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts, F-actin ring formation, and mineral resorption activity. AR-3 and AR-5 decreased RANKL-induced expression levels of osteoclast-specific marker genes such as c-Src, TRAP, and cathepsin K (CtsK) as well as c-Fos and nuclear factor of activated T cells cytoplasmic 1 (NFATc1). Mice treated with either AR-3 or AR-5 showed significant protection of the mice from lipopolysaccharide (LPS)-induced bone destruction and osteoclast formation. In particular, AR-5 suppressed RANKL-induced phosphorylation of JNK and ERK mitogen-activated protein kinases (MAPKs). The results suggest that AR-3 and AR-5 attenuate osteoclast formation in vitro and in vivo by suppressing RANKL-mediated MAPKs and NFATc1 signaling pathways and could potentially be lead compounds for the prevention or treatment of osteolytic bone diseases.


Asunto(s)
Resorción Ósea , Lipopolisacáridos/toxicidad , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ácido Oleanólico/análogos & derivados , Osteoclastos , Ligando RANK/metabolismo , Animales , Resorción Ósea/inducido químicamente , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/metabolismo , Resorción Ósea/patología , Ratones , Ratones Endogámicos ICR , Ácido Oleanólico/farmacología , Osteoclastos/metabolismo , Osteoclastos/patología , Células RAW 264.7
14.
BMC Infect Dis ; 20(1): 332, 2020 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-32393198

RESUMEN

BACKGROUND: Between 2016 and 2019, 265 cases of Zika virus (ZIKV) infection were reported in Vietnam, predominantly in southern Vietnam. In 2016, a case of ZIKV-associated microcephaly was confirmed in the Central Highlands, and several members of the infant's family were confirmed to be infected with ZIKV. The study aims to determine the level of immunity to ZIKV in the general population of the ZIKV epidemic region. METHODS: A total of 879 serum samples were collected from 801 participants between January 2017 and July 2018, during and after the ZIKV epidemic in Vietnam. The samples were tested for anti-ZIKV immunoglobulin M (IgM) and immunoglobulin G (IgG), and anti-dengue virus (DENV) IgG antibodies using enzyme-linked immunosorbent assays (ELISA). Plaque-reduction neutralization test (PRNT) for ZIKV was performed on all samples, and for DENV on the samples that ZIKV neutralizing antibody positive. RESULTS: A total of 83 (10.3%) participants had anti-ZIKV IgM. Of the 83, 6 were confirmed to be ZIKV antibodies positive using PRNT and anti-ZIKV IgG ELISA. Of the 718 participants who were anti-ZIKV IgM negative, a further 3 cases were confirmed as positive for antibodies against ZIKV. Of the 9 participants with ZIKV infection, 5 lived in the same village as the infant with ZIKV-associated microcephaly and the other 4 lived in 2 neighboring communes. Repeat samples were collected from the 83 ZIKV IgM positive participants 1.5 years after the first collection. No new cases of ZIKV infection were detected. In addition, 2 of 3 participants with anti-ZIKV NS1 IgG demonstrated a 4- to 8-fold increase in ZIKV neutralizing antibody titer. CONCLUSIONS: ZIKV was present in the area around Krong Buk, with the rate of ZIKV-specific antibodies was 1.1% in the community since at least 2016. While the low levels of circulation together with low seroprevalence suggests a limited outbreak in the region, the results also reflect on low levels of protective immunity to Zika within the population. These results provide a better understanding of the current ZIKV epidemic status in the region and demonstrate a need for implementation of more effective ZIKV infection control measures.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Epidemias , Infección por el Virus Zika/epidemiología , Virus Zika/inmunología , Adolescente , Adulto , Niño , Preescolar , Virus del Dengue/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Microcefalia/virología , Persona de Mediana Edad , Pruebas de Neutralización , Prevalencia , Estudios Seroepidemiológicos , Vietnam/epidemiología , Adulto Joven , Infección por el Virus Zika/virología
15.
Emerg Infect Dis ; 26(7): 1624-1626, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32240079

RESUMEN

We analyzed 2 clusters of 12 patients in Vietnam with severe acute respiratory syndrome coronavirus 2 infection during January-February 2020. Analysis indicated virus transmission from a traveler from China. One asymptomatic patient demonstrated virus shedding, indicating potential virus transmission in the absence of clinical signs and symptoms.


Asunto(s)
Enfermedades Asintomáticas , Betacoronavirus , Infecciones por Coronavirus/transmisión , Neumonía Viral/transmisión , Esparcimiento de Virus , Adolescente , Adulto , Anciano , COVID-19 , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Pandemias , SARS-CoV-2 , Viaje , Vietnam , Adulto Joven
16.
Am J Trop Med Hyg ; 102(6): 1217-1225, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32189614

RESUMEN

Dengue virus (DENV) infection is a major cause of morbidity and mortality in Vietnam, and the incidence is higher and more consistent in the southern part of the country. This study investigated the circulation of DENV serotypes, viremia levels, immunological status, and cytokine levels, with disease severities among children infected in 2017 in Ho Chi Minh City, Southern Vietnam. Acute and convalescent serum samples were collected from clinically diagnosed dengue children. They were confirmed to have DENV infection by NS1 antigen, IgM and IgG ELISAs, virus isolation, and conventional and real-time RT-PCR. Measurement of 10 cytokine levels was performed in the serum samples. All the children were dengue IgM positive; 28% and 72% of them had primary and secondary DENV infections, respectively, whereas 54% of those with secondary infection were children with dengue with warning signs and with severe dengue. Any or mixed infection of the four serotypes of DENV RNA was detected in 58 children. Twenty DENV strains (DENV-1 = 16 and DENV-4 = 4) were isolated. Levels of IFN-γ, TNF-α, MCP-1, IL-10, and IL-6 were significantly higher in severe dengue cases. We report the predominance of DENV-1 over other serotypes in the 2017 dengue outbreak in Southern Vietnam. Our data showed that cytokine expressions were correlated with dengue pathogenesis and may help in identifying an effective therapeutic strategy.


Asunto(s)
Citocinas/sangre , Dengue/sangre , Dengue/epidemiología , Adolescente , Anticuerpos Antivirales/sangre , Niño , Preescolar , Dengue/metabolismo , Dengue/patología , Brotes de Enfermedades , Femenino , Regulación de la Expresión Génica , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lactante , Masculino , Estudios Retrospectivos , Vietnam/epidemiología
18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-951217

RESUMEN

Objective: To determine the concentration and rate of decay of maternal IgG antibodies against measles prevalence in infants of vaccinated or naturally infected mothers and study initial measles immunization occurs in nine-month-old children. Methods: In total, 401 pregnant women and the same number of their subsequent newborns were recruited in the Bavi district of Hanoi in 2016-2017; they were divided into two groups: Older women (born before 1985, n=201) and younger women (born after 1990, n=200). Samples were collected at five time-points; week 36 of pregnancy, birth (cord), and 3, 6, and 9 months after birth. Measles-specific IgG antibody levels were recorded. Results: In total, 77.06% of the 401 pregnant women were seropositive for measles-specific IgG antibodies. A significantly greater proportion of mothers aged 30 and older (88.06%) and their newborn (93.53%) were seropositive compared to the mothers aged 25 and younger (66.00%), and their newborn (72.00%) (P<0.001). The infants of older mothers had significantly higher geometric mean titres (GMT) of measles IgG antibodies than the infants of younger mothers (P<0.001) at all time-points of the study period. The proportion of measles IgG antibodies together with GMT decreased from 82.97% (506.96) at the age of three months to 23.19% (45.22) at the age of nine months. Conclusions: This study provides a profile of maternal antibodies against measles in Vietnamese infants and investigates the early susceptibility to measles in both the infants of vaccinated mothers and mothers with naturally acquired immunity. These data suggest that determining the appropriate age for measles vaccination is paramount for the elimination of measles in Vietnam.

19.
BMC Infect Dis ; 18(1): 31, 2018 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-29321001

RESUMEN

BACKGROUND: Antibodies are critical responses to protect the host from dengue virus(DENV) infection. Antibodies target DENV by two pathologic mechanisms: virus neutralization and infection enhancement. In dengue patients, the absence of neutralizing activity in the presence of FcγR implies that infection-enhancing activity hampers the neutralizing activity of antibodies, which could potentially lead to symptomatic presentations and severe clinical outcomes. METHODS: A total of 100 pair serum samples from adult healthy volunteers were obtained during the dengue season in Ha Noi in 2015 for evaluation of neutralizing and infection-enhancing activity. Additionally, 20 serum samples from acute secondary DENV infection patients were also used as the patient group in this study. PRNT was performed on BHK cells and FcγR-expressing BHK cell lines for all serum samples. RESULTS: Out of 100 residents, positive neutralizing antibodies (N.A) were found in 44.23 and 76.92% for DENV-1; 38.46 and 75% for DENV-2; 19.23 and 15.38% for DENV-3; and 1.92 and 9.62% for DENV-4 for pre and post-dengue season respectively. The percentage of post-exposure residents having positive responses against single, two, or more than three DENV serotypes were 38.46, 44.23 and 15.38%, respectively. A total of 34 residents were DENV seropositive before the dengue season and these individuals demonstrated further elevation of IgG antibodies after the dengue season. At the end of the season, 18 residents were confirmed to be new asymptomatic DENV infection cases. In both groups, N.A titers determined on BHK cells were higher than that on FcγR-expressing BHK cells. In heterotypic N.A responses, N.A titers to the infecting serotype from the samples obtained from pre-exposure group were significantly higher than those of the patient group. However, fold enhancement to the infecting serotypes from the samples in the pre-exposure group was substantially lower as compared to that of the patient group. CONCLUSION: Before and after the dengue season, serum samples from healthy volunteers demonstrated high levels of neutralizing antibodies and low or absence of infection-enhancement activity. The results suggest that while infection-enhancement activity hampers neutralizing activity of antibodies, high levels of DENV neutralizing antibodies set a critical threshold in facilitating the prevention of disease progression.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Virus del Dengue/inmunología , Dengue/epidemiología , Dengue/inmunología , Receptores de IgG/metabolismo , Adulto , Animales , Anticuerpos Neutralizantes/inmunología , Línea Celular , Coinfección/virología , Cricetinae , Dengue/virología , Virus del Dengue/patogenicidad , Femenino , Voluntarios Sanos , Humanos , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Estaciones del Año , Serogrupo
20.
BMC Proc ; 12(Suppl 13): 62, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30807619

RESUMEN

Cholera remains a major public health problem in many countries. Poor sanitation and inappropriate clean water supply, insufficient health literacy and community mobilization, absence of national plans and cross-border collaborations are major factors impeding optimal control of cholera in endemic countries. In March 2017, a group of experts from 10 Asian cholera-prone countries that belong to the Initiative against Diarrheal and Enteric Diseases in Africa and Asia (IDEA), together with representatives from the World Health Organization, the US National Institutes of Health, International Vaccine Institute, Agence de médecine préventive, NGOs (Save the Children) and UNICEF, met in Hanoi (Vietnam) to share progress in terms of prevention and control interventions on water, sanitation and hygiene (WASH), surveillance and oral cholera vaccine use. This paper reports on the country situation, gaps identified in terms of cholera prevention and control and strategic interventions to bridge these gaps.

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