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1.
J Med Virol ; 96(6): e29761, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38924137

RESUMO

Globally, Group A rotavirus (RVA) is the leading cause of acute gastroenteritis in children under 5 years old, with Pakistan having the highest rates of RVA-related morbidity and mortality. The current study aims to determine the genetic diversity of rotavirus and evaluate the impact of Rotarix-vaccine introduction on disease epidemiology in Pakistan. A total of 4749 children, hospitalized with acute gastroenteritis between 2018 and 2020, were tested at four hospitals in Lahore and Karachi. Of the total, 19.3% (918/4749) cases were tested positive for RVA antigen, with the positivity rate varying annually (2018 = 22.7%, 2019 = 14.4%, 2020 = 20.9%). Among RVA-positive children, 66.3% were under 1 year of age. Genotyping of 662 enzyme-linked immuno sorbent assay-positive samples revealed the predominant genotype as G9P[4] (21.4%), followed by G1P[8] (18.9%), G3P[8] (11.4%), G12P[6] (8.7%), G2P[4] (5.7%), G2P[6] (4.8%), and 10.8% had mixed genotypes. Among vaccinated children, genotypes G9P[4] and G12P[6] were more frequently detected, whereas a decline in G2P[4] was observed. Phylogenetic analysis confirmed the continued circulation of indigenous genotypes detected earlier in the country except G9 and P[6] strains. Our findings highlight the predominance of G9P[4] genotype after the vaccine introduction thus emphasizing continual surveillance to monitor the disease burden, viral diversity, and their impact on control of rotavirus gastroenteritis in children.


Assuntos
Gastroenterite , Genótipo , Filogenia , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Vacinas Atenuadas , Humanos , Rotavirus/genética , Rotavirus/isolamento & purificação , Rotavirus/classificação , Gastroenterite/virologia , Gastroenterite/epidemiologia , Infecções por Rotavirus/virologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Vacinas contra Rotavirus/imunologia , Lactente , Pré-Escolar , Paquistão/epidemiologia , Feminino , Masculino , Vacinas Atenuadas/imunologia , Variação Genética , Fezes/virologia , Doença Aguda/epidemiologia
2.
J Environ Manage ; 345: 118868, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37659375

RESUMO

Geopolitical risks and environmental policy have become increasingly important in the European Union (EU), which is committed to tackling climate change and protecting the environment. However, geopolitical risks can undermine its environmental policy objectives. Thus, the study evaluates the relationship between geopolitical risks and environmental policy in nineteen EU countries from 1994 to 2020 through panel bootstrap Granger causality. The results show that geopolitical risks significantly influence environmental policy in Denmark, Estonia, Finland, France, Germany, Luxembourg, and Romania. On the other hand, the findings reveal that environmental policy causes geopolitical risks only in Latvia, while there is no relationship in the remaining countries. Therefore, policymakers must develop resilience to geopolitical risks, promote renewable energy, strengthen environmental regulations, and address social and economic implications to reduce environmental policy vulnerability to geopolitical risks.


Assuntos
Política Ambiental , União Europeia , Finlândia , França , Alemanha
3.
J Infect Dis ; 226(5): 843-851, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34791319

RESUMO

BACKGROUND: Elimination of poliovirus in Pakistan and Afghanistan is challenged by notions against the role of oral poliovirus vaccine (OPV) in eradicating contemporary wild poliovirus (WPV) strains. METHODS: A total of 1055 WPV type 1 (WPV1) strains isolated between 2013 and 2018 were categorized into 68 antigenic groups and tested for neutralization by OPV-derived antibodies. Molecular docking was conducted to determine neutralization efficiency of antibodies against WPV. The clinical significance of WPV1 variants was assessed to ascertain their role in patient outcomes. RESULTS: We found that 88% of WPV1 strains isolated from paralytic children belonged to a single antigenic lineage identical to the WPV1 strain detected in 1993. WPV1 antigenic variants were effectively neutralized by OPV-derived antibodies, with geometric mean titers comparable to the neutralization titers found for 3 strains in OPV (OPV1-3, 7.96-9.149 [95% confidence interval, 6.864-10.171]; WPV1 strains, 7.542-8.786 [6.493-9.869]). Docking examination underscored a strong antigen-antibody interaction despite variations within the viral protein 1 epitopes. There was no significant association (P = .78) with clinical prognosis among patients infected with antigenically diverse WPV1 strains and patient outcomes, including death. CONCLUSIONS: Our findings substantiate the robustness of OPV for neutralizing the contemporary WPV1 strains endemic in Pakistan and Afghanistan. Vaccination coverage must be augmented to achieve early eradication.


Assuntos
Poliomielite , Poliovirus , Criança , Erradicação de Doenças , Humanos , Programas de Imunização , Simulação de Acoplamento Molecular , Paquistão/epidemiologia , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Vacina Antipólio Oral , Vigilância da População
4.
Energy (Oxf) ; 256: 124607, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35774292

RESUMO

This article assesses the asymmetric multifractality of the energy prices in the different periods during the coronavirus pandemic (COVID-19) through asymmetric multifractality detrended fluctuation analysis. The higher (lower) multifractality shows a rapid rise (fall), which has different consequences for the energy prices. The findings explore strong multifractality in the downward movements for crude oil, heating oil, diesel, gasoline, propane and kerosene oil returns. The upside multifractality for coal and natural gas returns are bigger than the downside in both periods. Furthermore, the access asymmetry is more pronounced during the COVID-19, implying increased market inefficiency. The outcomes explore if energy prices are inefficient during the pandemic. A special attention is required in order to observe such unexpected fluctuations in the price dynamic and guidelines are vital. The level of efficiency can be improved by a greater transference in information while the government must play its role in regulations. Such aspects can increase stability and decrease the expected risks and price movements.

5.
Clin Infect Dis ; 71(7): e58-e67, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31665247

RESUMO

BACKGROUND: Pakistan is among 3 countries endemic for wild poliovirus type 1 (WPV1) circulation that are still struggling for eradication of poliomyelitis. Active clinical and environmental surveillance with meticulous laboratory investigations provide insights into poliovirus transmission patterns and genomic diversity to inform decisions for strategic operations required to achieve eradication. METHODS: We analyzed epidemiological and virological data to comprehend the current epidemiological status of WPV1 in Pakistan during 2015-2017. Stool specimens of patients with acute flaccid paralysis (AFP) and sewage samples collected from 60 environmental sites were tested. Viral culturing, intratypic differentiation by real-time polymerase chain reaction, and nucleic acid sequencing of the VP1 region of the poliovirus genome to determine genetic relatedness among WPV1 strains were applied. RESULTS: Poliovirus isolates were grouped into 11 distinct clusters, which had ≥95% nucleotide homology in the VP1 coding region. Most of the poliovirus burden was shared by 3 major reservoirs: Karachi, Peshawar, and Quetta block (64.2% in 2015, 75.4% in 2016, and 76.7% in 2017). CONCLUSIONS: Environmental surveillance reveals importations and pockets of unimmunized children that dictate intensive target mop-up campaigns to contain poliovirus transmission. A decrease in the number of orphan isolates reflects effective combination of AFP and environmental surveillance in Pakistan. The genetic data reflect sustained transmission within reservoir areas, further expanded by periodic importations to areas of high immunity reflected by immediate termination of imported viruses. Improved immunization coverage with high-quality surveillance is vital for global certification of polio eradication.


Assuntos
Poliomielite , Poliovirus , Criança , Erradicação de Doenças , Humanos , Epidemiologia Molecular , Paquistão/epidemiologia , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Poliovirus/genética , Vacina Antipólio Oral , Vigilância da População
6.
J Clin Microbiol ; 58(9)2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32611795

RESUMO

Global poliovirus surveillance involves virus isolation from stool and environmental samples, intratypic differential (ITD) by PCR, and sequencing of the VP1 region to distinguish vaccine (Sabin), vaccine-derived, and wild-type polioviruses and to ensure an appropriate response. This cell culture algorithm takes 2 to 3 weeks on average between sample receipt and sequencing. Direct detection of viral RNA using PCR allows faster detection but has traditionally faced challenges related to poor sensitivity and difficulties in sequencing common samples containing poliovirus and enterovirus mixtures. We present a nested PCR and nanopore sequencing protocol that allows rapid (<3 days) and sensitive direct detection and sequencing of polioviruses in stool and environmental samples. We developed barcoded primers and a real-time analysis platform that generate accurate VP1 consensus sequences from multiplexed samples. The sensitivity and specificity of our protocol compared with those of cell culture were 90.9% (95% confidence interval, 75.7% to 98.1%) and 99.2% (95.5% to 100.0%) for wild-type 1 poliovirus, 92.5% (79.6% to 98.4%) and 98.7% (95.4% to 99.8%) for vaccine and vaccine-derived serotype 2 poliovirus, and 88.3% (81.2% to 93.5%) and 93.2% (88.6% to 96.3%) for Sabin 1 and 3 poliovirus alone or in mixtures when tested on 155 stool samples in Pakistan. Variant analysis of sequencing reads also allowed the identification of polioviruses and enteroviruses in artificial mixtures and was able to distinguish complex mixtures of polioviruses in environmental samples. The median identity of consensus nanopore sequences with Sanger or Illumina sequences from the same samples was >99.9%. This novel method shows promise as a faster and safer alternative to cell culture for the detection and real-time sequencing of polioviruses in stool and environmental samples.


Assuntos
Sequenciamento por Nanoporos , Poliomielite , Poliovirus , Monitoramento Ambiental , Fezes , Humanos , Poliomielite/diagnóstico , Poliovirus/genética , Vacina Antipólio Oral
7.
Sensors (Basel) ; 19(24)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31835385

RESUMO

Ultrawideband (UWB) antennas are widely used as core devices in high-speed wireless communication. A novel compact UWB monopole antenna with an additional narrow band for Wi-Fi applications comprising a metamaterial (MTM) is proposed in this paper. The antenna has a compact size of 27 × 33 mm2 and consists of a V-shaped slot with two rectangular slots in the radiation patch. The inductance and capacitance develop due to the V-shaped slot in the radiation patch. The proposed antenna has -10 dB bandwidths of 3.2 GHz to 14 GHz for UWB and 2.38 GHz to 2.57 GHz for narrowband, corresponding to 144% and 7.66% fractional bandwidths, respectively. The measured gain and efficiency meet the desired values for UWB and Wi-Fi applications. To verify the performance of the antenna, the proposed antenna is fabricated and tested. The simulated and measured results agree well at UWB frequencies and Wi-Fi frequencies, and the antenna can be used as a smart device for portable IoT applications.

8.
J Med Virol ; 90(8): 1297-1303, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29704426

RESUMO

Despite the availability of an effective vaccine, the measles virus continues to cause significant morbidity and mortality in children worldwide. Molecular characterization of wild-type measles strains is an invaluable component of epidemiological studies or surveillance systems that provides important information pertinent to outbreak linkages and transmission pathways. Serum samples and throat swabs were collected from suspected measles cases from the Punjab province of Pakistan (2013-2015) and further tested for measles immunoglobulin M (IgM) through enzyme-linked immunosorbent assay and reverse-transcriptase polymerase chain reaction for molecular characterization. Among the total of 5415 blood samples, 59% tested positive for measles IgM. Males had a higher infection rate (55%) than females (45%), and the highest frequency of positive cases (63%) was found in the age group of 0 to 5 years. Partial sequencing of the nucleoprotein gene showed that 27 strains belonged to the B3 genotype, whereas 2 viruses were identified as D4. On phylogenetic analysis, Pakistani B3 strains were found to be closely related to previously reported indigenous strains and those from neighboring countries of Iran and Qatar. This is the first report on the detection of the measles B3 genotype from Punjab, Pakistan. The current study shows a high burden of measles infections in Punjab province owing to poor routine immunization coverage in major cities. It is imperative that national health authorities adopt strategic steps on an urgent basis for improvement of routine immunization coverage. Molecular epidemiology of the measles viruses circulating in different parts of the country can provide useful data to manage future outbreaks.


Assuntos
Surtos de Doenças , Genótipo , Vírus do Sarampo/classificação , Vírus do Sarampo/genética , Sarampo/epidemiologia , Adolescente , Fatores Etários , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Transmissão de Doença Infecciosa , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina M/sangue , Lactente , Recém-Nascido , Masculino , Vírus do Sarampo/isolamento & purificação , Epidemiologia Molecular , Proteínas do Nucleocapsídeo , Nucleoproteínas/genética , Paquistão/epidemiologia , Faringe/virologia , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Soro/virologia , Fatores Sexuais , Proteínas Virais/genética , Adulto Jovem
9.
Arch Virol ; 162(12): 3603-3610, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28803415

RESUMO

Measles continues to be a major public health issue causing substantial outbreaks worldwide, mostly affecting young children. Molecular analysis of measles viruses provides important information on outbreak linkages and transmission pathways that can be helpful towards implementation of appropriate control programs. In Pakistan, the control of measles is still tenuous, and progress towards elimination has been irregular and challenging. In the 2013 measles outbreak we received 4,682 sera collected from suspected patients in 23 districts across Sindh. A total of 3,283 samples were confirmed measles positive using IgM ELISA with the highest infection rate in children aged 1-12 months. Males were more affected than females and a visible peak was observed from January to April. Among the 3,283 cases, 59.1% were unvaccinated, 29.6% had received 1 dose and 10.3% had received 2 doses of measles vaccine while 0.85% had an unknown vaccination status. For genotype detection and phylogenetic analysis, 60 throat swab samples were collected from suspected patients below 15 years of age in eight districts of Sindh province. Forty four (73%; 44/60) throat swab samples were successfully genotyped using RT-PCR. Phylogenetic analyses based on partial sequences of the nucleocapsid protein gene revealed that all Pakistani measles virus strains belonged to genotype B3 and were closely related to those isolated from neighboring countries such as Iran, Afghanistan (99.1-100%) and India with 98.6 - 99.6% nucleotide homology. This is the first report on the phylogenetic analysis of measles B3 genotype strains from Pakistan and highlights the need for strengthening the surveillance systems and improving immunization coverage across the country.


Assuntos
Surtos de Doenças , Genótipo , Vírus do Sarampo/classificação , Vírus do Sarampo/isolamento & purificação , Sarampo/epidemiologia , Sarampo/virologia , Adolescente , Adulto , Distribuição por Idade , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Técnicas de Genotipagem , Humanos , Imunoglobulina M/sangue , Lactente , Masculino , Vacina contra Sarampo/administração & dosagem , Vírus do Sarampo/genética , Pessoa de Meia-Idade , Paquistão/epidemiologia , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Fatores Sexuais , Vacinação/estatística & dados numéricos , Adulto Jovem
10.
Clin Infect Dis ; 62(2): 190-198, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26417032

RESUMO

BACKGROUND: Despite tremendous efforts in the fight against polio, Pakistan bears the highest proportion of poliomyelitis cases among the 3 endemic countries including Afghanistan and Nigeria. Apart from insecurity and inaccessibility challenges, the substantial shift of unimmunized children from North Waziristan due to recent military operations was presumed to favor the widespread poliovirus infection in Pakistan. METHODS: To better understand the current epidemiological situation, we analyzed the virologic data of wild poliovirus type 1 (WPV1) strains detected in Pakistan during 2013-2015. RESULTS: Five genetic clusters (A-E) were identified with at least 5% nucleotide divergence in the viral protein 1 (VP1) coding region. Peshawar, Quetta, and Karachi were found to be the major endemic foci where multiple discrete genetic lineages of WPV1 were detected. Phylogenetic analysis suggests that wild poliovirus strains from endemic regions were genetically distant (with 5%-15% VP1 nucleotide divergence) from those detected in North Waziristan cases, excluding the possibility of a recent progenitor of WPV1 instigating single-source transmission across the country. Orphan lineages detected in Rawalpindi, Lahore, Hyderabad, Sukkur, and Jacobabad revealed silent transmission and the need for vigilant surveillance. Sustenance of analogous genetic lineages over a period of 3 years highlights multiple unimmunized foci present to maintain viral genetic diversity. CONCLUSIONS: Our findings are inconsistent with the hypothesis that impoverished populations from North Waziristan serve as a possible determinant of widespread poliomyelitis infection in Pakistan and further emphasize the need to scale-up clinical and environmental surveillance as well as immunization activities.


Assuntos
Transmissão de Doença Infecciosa , Genótipo , Poliomielite/epidemiologia , Poliomielite/virologia , Poliovirus/classificação , Poliovirus/genética , Pré-Escolar , Monitoramento Epidemiológico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Paquistão/epidemiologia , Filogenia , Poliomielite/transmissão , Poliovirus/isolamento & purificação
13.
J Med Virol ; 87(4): 656-63, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25611467

RESUMO

Human Bocaviruses (HBoV) have been detected in human respiratory and gastrointestinal infections worldwide. Four genotypes of HBoV (HBoV1-4) have been described; HBoV-1 is associated with respiratory tract infections while HBoV-2, -3, and -4 genotypes are considered as entero-pathogenic although the exact role largely remains unclear. The global prevalence of HBoV has been reported, but the epidemiological data from Pakistan is largely unavailable to date. This study was conducted to understand the genetic diversity and disease prevalence of HBoV in hospitalized Pakistani children with acute diarrhea. During 2009, a total of 365 stool samples were collected from children hospitalized with gastrointestinal symptoms (as per WHO case definitions) at Rawalpindi General Hospital, Pakistan. Demographic and clinical data were recorded using a standardized questionnaire. The samples were tested for HBoV and rotavirus using real-time RT-PCR and ELISA, respectively. There were 47 (13%) samples positive for HBoV with 98% (n = 46) showing co-infection with rotavirus. HBoV-1 was the most frequently detected and was found in 94% samples followed by HBoV-2 and HBoV-3 genotypes. The mean age of infected children was 7.57 ± 5.4 months while detection was more frequent in males (n = 32, 68%). All cases recovered after 2.43 ± 1.0 mean days of treatment. On phylogenetic analysis, HBoV strains from Pakistan clustered closely with viruses from neighboring Bangladesh and China. These findings represent the first known epidemiological study in Pakistan to investigate the role of HBoV in acute gastroenteritis. The clinical data demonstrates that HBoV is not significantly associated with gastroenteritis alone and predominantly co-infections with rotavirus are found.


Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Bocavirus Humano/isolamento & purificação , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Distribuição por Idade , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , Ensaio de Imunoadsorção Enzimática , Fezes/virologia , Feminino , Variação Genética , Genótipo , Bocavirus Humano/classificação , Bocavirus Humano/genética , Humanos , Lactente , Masculino , Epidemiologia Molecular , Filogenia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/genética , Rotavirus/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência , Distribuição por Sexo
15.
J Infect Dis ; 210 Suppl 1: S324-32, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25316851

RESUMO

BACKGROUND: The environmental surveillance has proven to be a useful tool to identify poliovirus circulation in different countries and was started in Pakistan during July 2009 to support the acute flaccid paralysis (AFP) surveillance system. METHODS: Sewage samples were collected from 27 environmental sampling (ENV) sites and processed for poliovirus isolation through 2-phase separation method. Poliovirus isolates were identified as Sabin-like or wild type through real-time polymerase chain reaction (PCR). Wild-type strains were subjected to VP1 gene sequencing and phylogenetic analysis performed using MEGA 5.0. RESULTS: During 2011-2013, a total of 668 samples were collected from 4 provinces that resulted in 40% of samples positive for wild poliovirus type-1 (WPV-1). None of the samples were positive for WPV-3. The areas with high frequency of WPV-1 detection were Karachi-Gadap (69%), Peshawar (82%), and Rawalpindi (65%), whereas the samples from Quetta and Sukkur remained negative for WPV during 2013. Phylogenetic analysis revealed 3 major clusters with multiple poliovirus lineages circulating across different country areas as well as in bordering areas of Afghanistan. CONCLUSIONS: Environmental surveillance in Pakistan has been proven to be a powerful tool to detect WPV circulation in the absence of poliomyelitis cases in many communities. Our findings emphasize the need to continue and expand such surveillance activities to other high-risk areas in the country.


Assuntos
Monitoramento Ambiental , Poliovirus/classificação , Poliovirus/isolamento & purificação , Esgotos/virologia , Proteínas do Capsídeo/genética , Análise por Conglomerados , Humanos , Paquistão , Filogenia , Poliovirus/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
16.
Virol J ; 11: 146, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25112200

RESUMO

BACKGROUND: The use of sequence independent methods combined with next generation sequencing for identification purposes in clinical samples appears promising and exciting results have been achieved to understand unexplained infections. One sequence independent method, Virus Discovery based on cDNA Amplified Fragment Length Polymorphism (VIDISCA) is capable of identifying viruses that would have remained unidentified in standard diagnostics or cell cultures. METHODS: VIDISCA is normally combined with next generation sequencing, however, we set up a simplified VIDISCA which can be used in case next generation sequencing is not possible. Stool samples of 10 patients with unexplained acute flaccid paralysis showing cytopathic effect in rhabdomyosarcoma cells and/or mouse cells were used to test the efficiency of this method. To further characterize the viruses, VIDISCA-positive samples were amplified and sequenced with gene specific primers. RESULTS: Simplified VIDISCA detected seven viruses (70%) and the proportion of eukaryotic viral sequences from each sample ranged from 8.3 to 45.8%. Human enterovirus EV-B97, EV-B100, echovirus-9 and echovirus-21, human parechovirus type-3, human astrovirus probably a type-3/5 recombinant, and tetnovirus-1 were identified. Phylogenetic analysis based on the VP1 region demonstrated that the human enteroviruses are more divergent isolates circulating in the community. CONCLUSION: Our data support that a simplified VIDISCA protocol can efficiently identify unrecognized viruses grown in cell culture with low cost, limited time without need of advanced technical expertise. Also complex data interpretation is avoided thus the method can be used as a powerful diagnostic tool in limited resources. Redesigning the routine diagnostics might lead to additional detection of previously undiagnosed viruses in clinical samples of patients.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Doenças Transmissíveis Emergentes/virologia , Fezes/virologia , Paraplegia/virologia , Viroses/virologia , Vírus/genética , Vírus/isolamento & purificação , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes/diagnóstico , Feminino , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Viroses/diagnóstico , Vírus/classificação
17.
Virus Evol ; 10(1): veae023, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38544854

RESUMO

Widespread surveillance, rapid detection, and appropriate intervention will be critical for successful eradication of poliovirus. Using deployable next-generation sequencing (NGS) approaches, such as Oxford Nanopore Technologies' MinION, the time from sample to result can be significantly reduced compared to cell culture and Sanger sequencing. We developed piranha (poliovirus investigation resource automating nanopore haplotype analysis), a 'sequencing reads-to-report' solution to aid routine poliovirus testing of both stool and environmental samples and alleviate the bioinformatic bottleneck that often exists for laboratories adopting novel NGS approaches. Piranha can be used for efficient intratypic differentiation of poliovirus serotypes, for classification of Sabin-like polioviruses, and for detection of wild-type and vaccine-derived polioviruses. It produces interactive, distributable reports, as well as summary comma-separated values files and consensus poliovirus FASTA sequences. Piranha optionally provides phylogenetic analysis, with the ability to incorporate a local database, processing from raw sequencing reads to an interactive, annotated phylogeny in a single step. The reports describe each nanopore sequencing run with interpretable plots, enabling researchers to easily detect the presence of poliovirus in samples and quickly disseminate their results. Poliovirus eradication efforts are hindered by the lack of real-time detection and reporting, and piranha can be used to complement direct detection sequencing approaches.

18.
BMC Infect Dis ; 13: 201, 2013 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-23641865

RESUMO

BACKGROUND: Pakistan is considered as an endemic country for Crimean-Congo Hemorrhagic fever with numerous outbreaks and sporadic cases reported during the past two decades. Majority of cases are reported from Baluchistan province with subsequent transmissions to non-endemic regions mainly through infected animals directly or via infested ticks. We hereby describe the molecular investigations of CCHF cases reported during 2008 in Quetta city of Baluchistan province. METHODS: Serum Samples from 44 patients, with clinical signs of hemorrhagic fever attending a tertiary care hospital in Quetta city, were collected and tested for CCHF virus antigen and genomic RNA, using capture IgM EIA kit and standard RT-PCR assay, respectively. The partial S-gene fragments were directly sequenced to get information related to the prevailing CCHFV genotypes and their molecular epidemiology in Pakistan. RESULTS: Out of the total forty four, sixteen (36%) samples were found positive for CCHF IgM. Similarly, viral RNA was detected in six (16%) samples. Phylogenetic analysis revealed that all study viruses belong to genotype Asia-1 with closest similarity (99-100%) to the previously reported strains from Pakistan, Afghanistan and Iran. CONCLUSION: We conclude that CCHF virus remains endemic within Baluchistan and its neighboring regions of Afghanistan warranting a need of incessant surveillance activities.


Assuntos
Doenças Endêmicas , Vírus da Febre Hemorrágica da Crimeia-Congo/classificação , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Febre Hemorrágica da Crimeia/epidemiologia , Febre Hemorrágica da Crimeia/virologia , Adolescente , Adulto , Idoso , Animais , Criança , Análise por Conglomerados , Feminino , Genótipo , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Paquistão/epidemiologia , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Análise de Sequência de DNA , Soro/virologia , Adulto Jovem
19.
Artigo em Inglês | MEDLINE | ID: mdl-36673826

RESUMO

Green technology innovation is one of the driving forces of industrial structure upgrading. This innovation is thought to be related to environmental regulation. The study uses panel data for 30 Chinese provinces and cities from 2009 to 2020 and presents a comprehensive research-based explanation of how environmental regulations impact green innovation. This study employs the spatial Durbin model to analyze the spillover effect of the region. The results show that the total impact of environmental regulations is 0.223%, of which the direct effect is 0.099%. This impact includes the effects of both formal and informal environmental regulation. It indicates that ecological regulations significantly enhance green technology innovation. Furthermore, the spatial spillover effect is significantly positive at the 1% level with a coefficient of 0.124. Such spillover effects represent a learning effect of regional environmental regulation. Based on the results, the study suggests a few policy measures based on the detailed outcomes.


Assuntos
Desenvolvimento Econômico , Invenções , Meio Ambiente , Indústrias , Cidades , China
20.
Microbiol Spectr ; : e0425222, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36939356

RESUMO

Direct detection by PCR of poliovirus RNA in stool samples provides a rapid diagnostic and surveillance tool that can replace virus isolation by cell culture in global polio surveillance. The sensitivity of direct detection methods is likely to depend on the choice of RNA extraction method and sample volume. We report a comparative analysis of 11 nucleic acid extraction methods (7 manual and 4 semiautomated) for poliovirus molecular detection using stool samples (n = 59) that had been previously identified as poliovirus positive by cell culture. To assess the effect of RNA recovery methods, extracted RNA using each of the 11 methods was tested with a poliovirus-specific reverse transcription-quantitative PCR (RT-qPCR), a pan-poliovirus RT-PCR (near-whole-genome amplification), a pan-enterovirus RT-PCR (entire capsid region), and a nested VP1 PCR that is the basis of a direct detection method based on nanopore sequencing. We also assessed extracted RNA integrity and quantity. The overall effect of extraction method on poliovirus PCR amplification assays tested in this study was found to be statistically significant (P < 0.001), thus indicating that the choice of RNA extraction method is an important component that needs to be carefully considered for any diagnostic based on nucleic acid amplification. Performance of the methods was generally consistent across the different assays used. Of the 11 extraction methods tested, the MagMAX viral RNA isolation kit used manually or automatically was found to be the preferable method for poliovirus molecular direct detection considering performance, cost, and processing time. IMPORTANCE Poliovirus, the causative agent of poliomyelitis, is a target of global eradication led by the World Health Organization since 1988. Direct molecular detection and genomic sequencing without virus propagation in cell culture is arguably a critical tool in the final stages of polio eradication. Efficient recovery of good-quality viral RNA from stool samples is a prerequisite for direct detection by nucleic acid amplification. We tested 11 nucleic acid extraction methods to identify those facilitating sensitive, fast, simple, and cost-effective extraction, with flexibility for manual and automated protocols considered. Several different PCR assays were used to compare the recovered viral RNA to test suitability for poliovirus direct molecular detection. Our findings highlight the importance of choosing a suitable RNA extraction protocol and provide useful information to diagnostic laboratories and researchers facing the choice of RNA extraction method for direct molecular virus detection from stool.

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