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1.
J Infect Chemother ; 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34635449

RESUMO

INTRODUCTION: In response to global outbreaks of infectious diseases, the need for support from organizations such as the World Health Organization Global Outbreak Alert and Response Network (GOARN) is increasing. Identifying the obstacles and support needs for applicants could increase GOARN deployments from Japan. METHODS: This cross-sectional study involved a web-based, self-administered questionnaire survey targeting Japanese participants in the GOARN Tier 1.5 training workshop, held in Tokyo in December 2019. RESULTS: All 47 Japanese participants in the workshop responded to the survey. Most responders were male and in their 30s and 40s. Participants specialized in case management (42.6%), infection prevention and control (25.6%), epidemiology and surveillance (19.1%). Only two participants (4.6%) had experienced a GOARN deployment. Their motivations for joining the GOARN training workshop were "Desire to be part of an international emerging infectious disease response team" (44.6%), "Interest in making an international contribution" (19.1%), and "Interest in working for the Japanese government in the field of international infectious diseases" (14.9%). Obstacles to GOARN deployments were "Making time for deployments" (45.7%) and "Lack of required professional skills and knowledge" (40.4%). The support needs for GOARN deployments constituted "Periodic simulation training" (51.1%), "Financial support during deployments" (44.7%), and "Technical support for deployments" (40.4%). CONCLUSIONS: Our study revealed the obstacles and support needs of Japanese candidates for GOARN deployment. Making time and upskilling for GOARN deployment were the main obstacles. More practical training (like GOARN Tier 2.0) with other supports are needed. The national framework is desirable to realize these supports.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34574555

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19). Real-time RT-PCR is the most commonly used method for COVID-19 diagnosis. However, serological assays are urgently needed as complementary tools to RT-PCR. Hachim et al. 2020 and Burbelo et al. 2020 demonstrated that anti-nucleocapsid(N) SARS-CoV-2 antibodies are higher and appear earlier than the spike antibodies. Additionally, cross-reactive antibodies against N protein are more prevalent than those against spike protein. We developed a less cross-reactive immunoglobulin G (IgG) indirect ELISA by using a truncated recombinant SARS-CoV-2 N protein as assay antigen. A highly conserved region of coronaviruses N protein was deleted and the protein was prepared using an E. coli protein expression system. A total of 177 samples collected from COVID-19 suspected cases and 155 negative control sera collected during the pre-COVID-19 period were applied to evaluate the assay's performance, with the plaque reduction neutralization test and the commercial SARS-CoV-2 spike protein IgG ELISA as gold standards. The SARS-CoV-2 N truncated protein-based ELISA showed similar sensitivity (91.1% vs. 91.9%) and specificity (93.8% vs. 93.8%) between the PRNT and spike IgG ELISA, as well as also higher specificity compared to the full-length N protein (93.8% vs. 89.9%). Our ELISA can be used for the diagnosis and surveillance of COVID-19.


Assuntos
COVID-19 , Proteínas do Nucleocapsídeo , Anticorpos Antivirais , Teste para COVID-19 , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Humanos , Imunoglobulina G , Proteínas do Nucleocapsídeo/genética , SARS-CoV-2 , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus
3.
Artigo em Inglês | MEDLINE | ID: mdl-34574767

RESUMO

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.


Assuntos
COVID-19 , Flavivirus , Humanos , SARS-CoV-2 , Viremia , Eliminação de Partículas Virais
4.
PLoS One ; 16(9): e0257452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34582459

RESUMO

OBJECTIVES: A few studies on antibody testing have focused on asymptomatic or mild coronavirus disease 2019 (COVID-19) patients with low initial anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses. Anti-SARS-CoV-2 antibody-testing performance was evaluated using blood samples from asymptomatic or mild COVID-19 patients. METHODS: Blood samples were collected from 143 COVID-19 patients during an outbreak on a cruise ship 3 weeks after diagnosis. Simultaneously, a follow-up SARS-CoV-2 genetic test was performed. Samples stored before the COVID-19 pandemic were also used to evaluate the lateral flow immunochromatographic assay (LFA) and electrochemiluminescence immunoassay (ECLIA). Titers of anti-SARS-CoV-2 IgM and IgG antibodies against the nucleocapsid and spike proteins were measured using the enzyme-linked immunosorbent assay to confirm which antibodies were influenced on LFA- and ECLIA- false-negative result in crew-member samples. RESULTS: Sensitivity, specificity, positive-predictive, and negative-predictive values of LFA-detected IgM antibodies were 0.231, 1.000, 1.000, and 0.613, respectively; those of LFA-detected IgG antibodies were 0.483, 0.989, 0.972, and 0.601, respectively; and those of ECLIA-detected total antibodies were 0.783, 1.000, 1.000, and 0.848, respectively. All antibody titers measured using ELISA were significantly lower in blood samples with negative results than in those with positive results in both LFA and ECLIA. In the patients with negative results from the follow-up genetic testing, IgM-, IgG-, and total-antibody positivity rates were 22.9%, 47.6%, and 72.4%, respectively. CONCLUSIONS: These findings suggest that anti-SARS-CoV-2 antibody testing has lower performance in asymptomatic or mild COVID-19 patients than required in the guidelines.

5.
Jpn J Infect Dis ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34470963

RESUMO

Human coronaviruses (HCoVs) are globally distributed and cause a range of respiratory symptoms. Reports of the clinical features of HCoV infection are limited, especially in adults because of mild upper respiratory tract disease and no specific therapy available. Here we aim to evaluate the features of HCoV infection in clinical settings. Adult patients with respiratory symptoms from October 2014 to September 2019 at Nagasaki Genbaku Isahaya Hospital were enrolled. The multiplex reverse-transcription polymerase chain reaction (RT-PCR) was performed for 15 viruses including HCoVs and 8 bacterial species on their respiratory specimens. A total of 121 cases were recruited with HKU1, OC43, 229E and NL63 strains in 80, 21, 12 and 11 cases, respectively. The percent of HCoV-infected patients peaked (47.5%) in winter. Symptoms of fever (69.4%) and cough (47.9%), and comorbidities of asthma/cough variant asthma (34.7%) were frequently observed. Lymphocytopenia and increased C-reactive protein were observed on the laboratory test. Co-infection with other viruses was identified in 38.8% of cases. In the repeat-positive cases, 42% cases were repeat positive within 100 days. HCoV-infected patients showed winter seasonality with a high frequency of comorbidity with asthma, and co-infection. Re-infection within an early period was suspected but required further consideration.

6.
Viruses ; 13(8)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34452310

RESUMO

Dengue virus (DENV) is one of the most prevalent neglected tropical diseases, with half of the world's population at risk of infection. In Nepal, DENV was first reported in 2004, and its prevalence is increasing every year. The present study aimed to obtain and characterize the full-length genome sequence of DENV from the 2017 outbreak. Hospital-based surveillance was conducted in two provinces of Nepal during the outbreak. Acute-phase serum samples were collected from 141 clinically suspected dengue patients after the rainy season. By serological and molecular techniques, 37 (26.9%) and 49 (34.8%), respectively, were confirmed as dengue patients. The cosmopolitan genotype of DENV-2 was isolated from 27 laboratory-confirmed dengue patients. Genomic analysis showed many amino acid substitutions distributed mainly among the E, NS3, and NS5 genes. Phylogenetic analyses of the whole genome sequence revealed two clades (Asian and Indian) among DENV-2 isolates from Nepal. The DENV isolates from hilly and Terai areas were similar to Asian and Indian strains, respectively. Further genomic study on different DENV serotypes is warranted to understand DENV epidemics in Nepal, where there are limited scientific resources and infrastructure.

7.
Viruses ; 13(7)2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202565

RESUMO

Arenaviruses and coronaviruses include several human pathogenic viruses, such as Lassa virus, Lymphocytic choriomeningitis virus (LCMV), SARS-CoV, MERS-CoV, and SARS-CoV-2. Although these viruses belong to different virus families, they possess a common motif, the DED/EDh motif, known as an exonuclease (ExoN) motif. In this study, proof-of-concept studies, in which the DED/EDh motif in these viral proteins, NP for arenaviruses, and nsp14 for coronaviruses, could be a drug target, were performed. Docking simulation studies between two structurally different chemical compounds, ATA and PV6R, and the DED/EDh motifs in these viral proteins indicated that these compounds target DED/EDh motifs. The concentration which exhibited modest cell toxicity was used with these compounds to treat LCMV and SARS-CoV-2 infections in two different cell lines, A549 and Vero 76 cells. Both ATA and PV6R inhibited the post-entry step of LCMV and SARS-CoV-2 infection. These studies strongly suggest that DED/EDh motifs in these viral proteins could be a drug target to combat two distinct viral families, arenaviruses and coronaviruses.


Assuntos
Antivirais/farmacologia , Exorribonucleases/antagonistas & inibidores , Vírus da Coriomeningite Linfocítica/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Células A549 , Motivos de Aminoácidos , Animais , Chlorocebus aethiops , Descoberta de Drogas , Humanos , Simulação de Acoplamento Molecular , Células Vero
8.
Viruses ; 13(6)2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208667

RESUMO

Dengue fever, caused by the mosquito-borne dengue virus (DENV), has been endemic in Myanmar since 1970 and it has become a significant public health burden. It is crucial that circulating DENV strains are identified and monitored, and that their transmission efficiency and association with disease severity is understood. In this study, we analyzed DENV-1, DENV-2, DENV-3, and DENV-4 serotypes in 1235 serum samples collected in Myanmar between 2017 and 2019. Whole-genome sequencing of DENV-1-4 demonstrated that most DENV-1-4 strains had been circulating in Myanmar for several years. We also identified the emergence of DENV-3 genotype-I in 2017 samples, which persisted through 2018 and 2019. The emergence of the strain coincided with a period of increased DENV-3 cases and marked changes in the serotype dynamics. Nevertheless, we detected no significant differences between serum viral loads, disease severity, and infection status of individuals infected with different DENV serotypes during the 3-year study. Our results not only identify the spread of a new DENV-3 genotype into Yangon, Myanmar, but also support the importance of DENV evolution in changing the epidemic dynamics in endemic regions.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Vírus da Dengue/classificação , Vírus da Dengue/genética , Dengue/epidemiologia , Dengue/virologia , Genótipo , Adolescente , Substituição de Aminoácidos , Criança , Pré-Escolar , Dengue/diagnóstico , Dengue/história , Vírus da Dengue/isolamento & purificação , Surtos de Doenças , Variação Genética , Genoma Viral , História do Século XXI , Humanos , Mianmar , Filogenia , Estudos Soroepidemiológicos , Sorogrupo , Sequenciamento Completo do Genoma
9.
Viruses ; 13(6)2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198717

RESUMO

In this study, we investigated severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) infection in cats in Nagasaki, Japan. In total, 44 of 133 (33.1%) cats with suspected SFTS were confirmed to be infected with SFTSV. Phylogenetic analyses of SFTSV isolates from cats indicated that the main genotype in Nagasaki was J1 and that unique reassortant strains with J2 (S segment) and unclassified genotypes (M and L segments) were also present. There were no significant differences in virus growth in cell cultures or fatality in SFTSV-infected mice between the SFTSV strains that were isolated from recovered and fatal cat cases. Remarkably, SFTSV RNAs were detected in the swabs from cats, indicating that the body fluids contain SFTSV. To evaluate the risk of SFTSV infection when providing animal care, we further examined the seroprevalence of SFTSV infection in veterinarian staff members; 3 of 71 (4.2%) were seropositive for SFTSV-specific antibodies. Our results provide useful information on the possibility of using cats as sentinel animals and raised concerns of the zoonotic risk of catching SFTSV from animals.


Assuntos
Doenças do Gato/epidemiologia , Phlebovirus , Febre Grave com Síndrome de Trombocitopenia/epidemiologia , Médicos Veterinários , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Doenças do Gato/virologia , Gatos , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Japão/epidemiologia , Phlebovirus/classificação , Phlebovirus/genética , Filogenia , RNA Viral , Febre Grave com Síndrome de Trombocitopenia/veterinária , Febre Grave com Síndrome de Trombocitopenia/virologia
10.
J Infect Chemother ; 27(10): 1525-1528, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34294531

RESUMO

Polymerase chain reaction (PCR) testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is necessary for confirming a diagnosis of Coronavirus disease 2019 (COVID-19). Here we present a COVID-19 case of an elderly woman whose SARS-CoV-2 PCR tests showed false negative repeatedly by evaluating with different sampling sites and procedures. Nasopharyngeal swabs, suctioned sputum, and tongue swabs were collected for SARS-CoV-2-PCR. As for tongue swabs, we compared between two different sample conditions; one obtained with dry condition and the other obtained with moistened condition inside the oral cavity. SARS-CoV-2-PCR showed positive for an extended period with suctioned sputum samples compared with nasopharyngeal swabs and tongue swabs. No SARS-CoV-2 from a nasopharyngeal swab sample obtained on day 46 after symptoms onset was isolated despite high viral load (183740.5 copies/5µL). An adequate production of neutralizing antibody in a serum sample on day 46 was also confirmed. The number of RNA copies of the tongue swab samples was higher with moistened condition than with dry condition. The present case suggests that the difference of sampling site or sample condition can affect PCR results. High loads viral RNA detection does not always correlate with infectivity.


Assuntos
COVID-19 , SARS-CoV-2 , Idoso , Feminino , Humanos , Nasofaringe , Reação em Cadeia da Polimerase , RNA Viral , Manejo de Espécimes
11.
PLoS One ; 16(6): e0251314, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086703

RESUMO

BACKGROUND: Dengue (DEN) is a neglected tropical disease, and surveillance of dengue virus (DENV) serotypes and genotypes is critical for the early detection of outbreaks. Risk factors for outbreaks include the emergence of new genotypes and serotype shifting. METHODOLOGY AND PRINCIPAL FINDINGS: To understand the genomic and viral characteristics of DENV-infected patients, we conducted a cross-sectional descriptive study among pediatric patients admitted at the 550-bedded Mandalay Children Hospital during the 2018 DEN endemic season. We conducted virus isolation, serological tests, viremia level measurement, and whole-genome sequencing. Among the 202 serum samples, we detected 85 samples with DENV (46 DENV-1, 10 DENV-3, 26 DENV-4 and three multiple serotype co-infections) via reverse transcription quantitative/real-time PCR (RT-qPCR), and we obtained 49 DENV isolates (31 DENV-1, 10 DENV-3 and 8 DEN-4). We did not detect DENV-2 in this study. The viral genome levels in serum did not differ significantly among virus serotypes, infection status (primary versus secondary) and disease severity. Based on the phylogenetic analysis, we identified DENV-1 genotype-1, DENV-4 genotype-1 and DENV-3 genotype-3 and genotype-1 which was detected for the first time. Next-generation sequencing analysis revealed greater frequencies of nonsynonymous and synonymous mutations per gene in the nonstructural genes. Moreover, mutation rates were also higher among DENV-1. CONCLUSION/SIGNIFICANCE: In conclusion, there was an increasing trend of DENV-3 cases during DENV endemic season in 2018 with the first detection of the genotype 1. However, DENV-1 has remained the predominant serotype in this study area since 2013, and we identified stop codon mutations in the DENV-1 genome. This report is the first to feature a complete genome analysis of the strains of DENV-3 and DENV-4 circulating among pediatric patients in Myanmar. This study highlighted the importance of annual surveillance for a better understanding of the molecular epidemiology of DENVs.

12.
PLoS One ; 16(6): e0252964, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34111203

RESUMO

OBJECTIVES: The accurate detection of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is essential for the diagnosis of coronavirus disease 2019 (COVID-19). We compared the quantitative RT-PCR results between nasopharyngeal swabs and saliva specimens. METHODS: A COVID-19 outbreak occurred on a cruise ship at Nagasaki port, Japan. We obtained 123 nasopharyngeal swabs and saliva each from asymptomatic or mild patients in the late phase of infection. RESULTS: The intervals from the diagnosis to the sampling were 25.5 days for nasopharyngeal swabs and 28.9 days for saliva. The positive rate was 19.5% (24/123) for nasopharyngeal swabs and 38.2% (47/123) for saliva (P = 0.48). The quantified viral copies (mean ± SEM copies/5 µl) were 9.3±2.6 in nasopharyngeal swabs and 920±850 in saliva (P = 0.0006). CONCLUSIONS: The advantages of saliva specimens include positive rate improvement and accurate viral load detection. Saliva may be used as a reliable sample for SARS-CoV-2 detection.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , Nasofaringe/virologia , SARS-CoV-2/isolamento & purificação , Saliva/virologia , Humanos , Manejo de Espécimes
13.
Antiviral Res ; 192: 105121, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34175321

RESUMO

Zika virus (ZIKV) is a re-emerging mosquito-borne flavivirus of African origin that is transmitted by Aedes mosquitoes. ZIKV was historically limited to Africa and Asia, where mild cases were reported. However, ZIKV has recently been responsible for major global outbreaks associated with a wide range of neurological complications. Since no antiviral therapy exists for ZIKV, drug discovery research for ZIKV is crucial. Intracellular lipids regulated by sterol regulatory element-binding proteins (SREBPs) are important in flavivirus pathogenesis. PF-429242 has been reported to inhibit the activity of site-1 protease (S1P), which regulates the expression of SREBP target genes. Our primary objective in this study is to elucidate the mechanism of the antiviral activity of PF-429242 against the African genotype (ZIKVMR-766) and Asian genotypes (ZIKV H/PF 2013 and ZIKV PRVABC59) using several primate-derived cell lines. The virus titer was determined via a focus-forming assay; we used flow cytometry to quantify intracellular lipids in ZIKV-infected and mock-treated cells. The PF-429242 molecule effectively suppressed ZIKV infection in neuronal cell lines; T98G, U-87MG, SK-N-SH and primary monocytes cell, indicating that PF-429242 molecule can be used therapeutically. A strong reduction in ZIKV replication was observed at 12 µM and 30 µM in in neuronal cell lines and primary monocytes, respectively. Interestingly, the inhibitory effects of the PF-429242 molecule were observed when it was tested on various ZIKV-lineage infections. Lipid quantification reveals that ZIKV increases lipogenesis in infected cells, while the exogenous addition of cholesterol effectively blocks ZIKV replication. Furthermore, the supplementation of oleic acid increases the ZIKV titer. Fenofibrate, an inhibitor of lipid droplet formation, reduces the ZIKV titer. Collectively, our results demonstrate that the development of antiviral drugs against ZIKV could be based on key regulators of lipid metabolism. In addition, this study reveals that the mechanism of the PF-429242-mediated suppression among flavivirus infections is not entirely identical. Our results warrant further evaluation of PF-429242 as a prospective antiviral drug, given the multiple advantageous properties of this compound, such as its limited toxicity, neuroprotective properties, and broad spectrum of capabilities.

14.
Jpn J Infect Dis ; 74(5): 443-449, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-33642435

RESUMO

During the 2017 outbreak of severe dengue in Sri Lanka, dengue virus (DENV) serotypes 2, 3, and 4 were found to be co-circulating. Our previous study of 295 patients from the National Hospital Kandy in Sri Lanka between March 2017 and January 2018 determined that the dominant infecting serotype was DENV-2. In this study, we aimed to characterize the DENV-3 strains from non-severe and severe dengue patients from our previous study population. Patients' clinical records and previous laboratory tests, including dengue-specific nonstructural protein 1 antigen rapid test and IgM-capture and IgG enzyme-linked immunosorbent assays, were analyzed together with the present results of real-time reverse transcription polymerase chain reaction and next-generation sequencing of DENV-3. Complete genome analysis determined that DENV-3 isolates belonged to 2 different clades of genotype I and were genetically close to strains from Indonesia, China, Singapore, Malaysia, and Australia. There were 16 amino acid changes among DENV-3 isolates, and a greater number of changes were found in nonstructural proteins than in structural proteins. The emergence of DENV-3 genotype I was noted for the first time in Sri Lanka. Continuous monitoring of this newly emerged genotype and other DENV serotypes and genotypes is needed to determine their effects on future outbreaks and understand the molecular epidemiology of dengue.

15.
J Psychiatr Res ; 136: 296-305, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33631655

RESUMO

BACKGROUND: This study explored the behavioural responses and anxiety symptoms of the general adult population in Japan during the ongoing coronavirus disease 2019 (COVID-19) outbreak. METHODS: A web-based cross-sectional survey was conducted between 12th and May 13, 2020. Quota sampling was used to attain equal gender and age distributions representative of the Japanese population. RESULTS: A total of 4127 complete responses were analysed. Higher educational level (B = 0.045, p = 0.002) and household income (B = 0.04, p = 0.009) were associated with a higher increase in preventive measures when comparing before and after the state of emergency was declared. The highest reported social anxiety was a feeling of fear (65.6%), followed by embarrassment (43.8%), keeping infection a secret (41.3%), avoidance (41.3%), and stigma (25.5%). A total of 86.1% of the respondents reported moderate to severe anxiety. The partial least square-based structural equation modelling (PLS-SEM) revealed that being female has the greatest effect (B = 0.246, p < 0.0001) on higher current preventive measures, followed by social anxiety (B = 0.119; p = 0.001) and State-Trait Anxiety Inventory scores (B = 0.153; p < 0.001). Perceived susceptibility (B = 0.033, p = 0.020), knowing someone who have been diagnosed with COVID-19 (B = 0.097, p < 0.001), higher income (B = 0.079, p < 0.001) and educational level (B = 0.045; p = 0.004) all had a small but significant effect on influencing levels of preventive measures. CONCLUSIONS: A moderate level of preventive practices found in this study indicates the need to encourage behavioural change to limit the spread of the coronavirus. The provision of mental health services is warranted as anxiety symptoms are prevalent.


Assuntos
Ansiedade/epidemiologia , COVID-19/epidemiologia , Pandemias , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Fobia Social/epidemiologia , Prevalência , Adulto Jovem
16.
Biochem Biophys Res Commun ; 545: 203-207, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33571909

RESUMO

The current COVID-19 pandemic requires urgent development of effective therapeutics. 5-amino levulinic acid (5-ALA) is a naturally synthesized amino acid and has been used for multiple purposes including as an anticancer therapy and as a dietary supplement due to its high bioavailability. In this study, we demonstrated that 5-ALA treatment potently inhibited infection of SARS-CoV-2, a causative agent of COVID-19, in cell culture. The antiviral effects could be detected in both human and non-human cells, without significant cytotoxicity. Therefore, 5-ALA is worth to be further investigated as an antiviral drug candidate for COVID-19.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , Ácidos Levulínicos/farmacologia , Animais , Antivirais/administração & dosagem , COVID-19/prevenção & controle , COVID-19/virologia , Células CACO-2 , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Compostos Ferrosos/farmacologia , Humanos , Ácidos Levulínicos/administração & dosagem , Células Vero
17.
Int J Mol Sci ; 21(21)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167379

RESUMO

The goal of the study was to develop a specific, sensitive, and cost-effective molecular RT-PCR diagnostic assay for the rapid and simultaneous detection of the serotypes of dengue virus (DENV) and Chikungunya virus (CHIKV) from sera of suspected febrile patients. A single-tube, single-step multiplex RT-PCR (mRT-PCR) assay was designed for the detection of viral genomes from clinical and field samples. Specificity and sensitivity of the mRT-PCR assay were evaluated against six different combinations using two reverse transcriptases (AMV-RT and RT-Ace) and three DNA polymerases (LA-Taq, rTaq, and Tth). Among the six combinations, the AMV-RT and LA-Taq combination was more specific and sensitive than other enzyme combinations for detecting viral genomes of DENV-1, DENV-2, DENV-3, and DENV-4 (p < 0.01), and for detecting viral genomes of CHIKV (p < 0.05). The detection limits of the mRT-PCR were 10 focus forming units (FFU) for CHIKV and 1 FFU, 20 FFU, 0.1 FFU, and 10 FFU for DENV-1, DENV-2, DENV-3, and DENV-4, respectively. The primers used for the mRT-PCR did not show any cross-reactivity among the serotypes of DENV or CHIKV. Specificity and sensitivity of the newly developed mRT-PCR were validated using serum samples collected from febrile patients during dengue outbreaks in Bangladesh. The sensitivity for serotype detection of DENV and CHIKV was superior to the virus isolation method and the antigen detection method using the Dengue NS1-Ag assay. This novel mRT-PCR method can be used for molecular epidemiological surveillance of DENV and CHIKV in epidemic and endemic countries.


Assuntos
Febre de Chikungunya/diagnóstico , Vírus Chikungunya/genética , Vírus da Dengue/genética , Dengue/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Aedes/virologia , Animais , Bangladesh , Células Cultivadas , Febre de Chikungunya/sangue , Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Cricetinae , Dengue/sangue , Dengue/virologia , Vírus da Dengue/isolamento & purificação , Humanos , Técnicas de Diagnóstico Molecular/métodos , RNA Viral/genética , RNA Viral/isolamento & purificação , Sensibilidade e Especificidade , Sorogrupo , Virologia/métodos
18.
Emerg Infect Dis ; 26(11): 2741-2745, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079056

RESUMO

In 2019, an outbreak of chikungunya virus infection occurred in Mandalay, Myanmar, and 3.2% of blood donors and 20.5% of patients who were children were confirmed as being infected. The prevalence rate was up to 6.3% among blood donors. The East Central/South African genotype was predominantly circulating during this outbreak.


Assuntos
Doadores de Sangue , Febre de Chikungunya , Vírus Chikungunya/isolamento & purificação , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/genética , Criança , Surtos de Doenças , Genótipo , Humanos , Mianmar/epidemiologia , Filogenia
20.
Am J Trop Med Hyg ; 103(5): 2059-2064, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32815502

RESUMO

To detect congenital ZIKV infection (CZI) in a birth cohort and among high-risk neonates in Vietnam, we collected umbilical cord blood plasma samples of newly delivered babies and peripheral plasma samples of high-risk neonates in Nha Trang, central Vietnam, between July 2017 and September 2018. Samples were subjected to serological and molecular tests. Of the 2013 newly delivered babies, 21 (1%) were positive for Zika virus (ZIKV) IgM and 1,599 (79%) for Flavivirus IgG. Among the 21 ZIKV IgM-positives, 11 were confirmed to have CZI because their plasma samples had anti-ZIKV neutralization titers ≥ 4 times higher than those against dengue virus (DENV)-1 to 4 and Japanese encephalitis virus (JEV) and were tested for the ZIKV RNA positive by real-time reverse transcription-PCR. Therefore, the incidence of CZI in our birth cohort was approximately 0.5%. Of the 150 high-risk neonates, three (2%) and 95 (63%) were positive for ZIKV IgM and Flavivirus IgG antibodies, respectively. None of the three ZIKV IgM-positives had ≥ 4 times higher anti-ZIKV neutralization titers than those against DENV-1 to 4 and JEV, and were therefore considered as probable CZI. Our results indicate that CZI is not rare in Vietnam. Although those with confirmed CZI did not show apparent symptoms suspected of congenital Zika syndrome at birth, detailed examinations and follow-up studies are needed to clarify the CZI impact in Vietnam. This is the first report of CZI cases in a birth cohort in Asia.


Assuntos
Infecção por Zika virus/congênito , Infecção por Zika virus/epidemiologia , Animais , Chlorocebus aethiops , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Masculino , Células Vero , Vietnã/epidemiologia
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