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1.
J Med Virol ; 94(7): 3404-3409, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35211985

RESUMEN

International travel has been the major source for the rapid spread of new SARS-CoV-2 variants across the globe. During SARS-CoV-2 genomic surveillance, a total of 212 SARS-CoV-2 positive clinical specimens were sequenced using next-generation sequencing. A complete SARS-CoV-2 genome could be retrieved from 90 clinical specimens. Of them, 14 sequences belonged to the Eta variant from clinical specimens of international travelers (n = 12) and local residents (n = 2) of India, and 76 belonged to other SARS-CoV-2 variants. Of all the Eta-positive specimens, the virus isolates were obtained from the clinical specimens of six international travelers. Many variants of interest have been found to cause substantial community transmission or cluster infections. The detection of this variant with lethal E484K mutation across the globe and India necessitates persistent genomic surveillance of the SARS-CoV-2 variants, which would aid in taking preventive action.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/epidemiología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación , SARS-CoV-2/genética
2.
BMC Infect Dis ; 21(1): 162, 2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33563231

RESUMEN

BACKGROUND: In June 2019, Nipah virus (NiV) infection was detected in a 21-year-old male (index case) of Ernakulum, Kerala, India. This study was undertaken to determine if NiV was in circulation in Pteropus species (spp) in those areas where the index case had visit history in 1 month. METHODS: Specialized techniques were used to trap the Pteropus medius bats (random sampling) in the vicinity of the index case area. Throat and rectal swabs samples of 141 bats along with visceral organs of 92 bats were collected to detect the presence of NiV by real-time reverse transcriptase-polymerase chain reaction (qRTPCR). Serum samples of 52 bats were tested for anti-NiV Immunoglobulin (Ig) G antibodies by Enzyme-Linked Immunosorbent Assay (ELISA). The complete genome of NiV was sequenced by next-generation sequencing (NGS) from the tissues and swab samples of bats. RESULTS: One rectal swab sample and three bats visceral organs were found positive for the NiV. Interestingly, 20.68% (12/58) of Pteropus were positive for anti-NiV IgG antibodies. NiV sequences of 18,172; 17,200 and 15,100 nucleotide bps could be retrieved from three Pteropus bats. CONCLUSION: A distinct cluster of NiV sequences, with significant net-evolutionary nucleotide divergence, was obtained, suggesting the circulation of new genotype (I-India) in South India. NiV Positivity in Pteropus spp. of bats revealed that NiV is circulating in many districts of Kerala state, and active surveillance of NiV should be immediately set up to know the hotspot area for NiV infection.


Asunto(s)
Quirópteros/virología , Infecciones por Henipavirus/diagnóstico , Virus Nipah/genética , Animales , Anticuerpos Antivirales/sangre , Brotes de Enfermedades , Infecciones por Henipavirus/epidemiología , Infecciones por Henipavirus/veterinaria , Infecciones por Henipavirus/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Inmunoglobulina G/sangre , India/epidemiología , Virus Nipah/clasificación , Virus Nipah/inmunología , Filogenia , ARN Viral/química , ARN Viral/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Recto/virología
3.
Indian J Med Res ; 154(4): 592-597, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-35435344

RESUMEN

Background & objectives: Varicella zoster virus (VZV) strains are classified into six different clades based on the sequencing of its genome. Clades 4 and 5 are reported from India based on the single-nucleotide polymorphism (SNP). Till now, multiple clade circulations using partial sequences have been reported from India due to the lack of availability of the full VZV genome sequence. This study conducted a genome sequencing of VZV in India to identify circulating clade. Methods: Four clinical samples obtained from symptomatic patients tested positive for VZV by real-time PCR were used. These four samples were preferred to retrieve the genomic VZV sequence using the next-generation sequencing method. A reference-based assembly method was used to retrieve the genome of VZV, which was further analyzed. Results: At the least, 98 per cent of the whole-genome sequences were recovered from the four samples. The VZV sequences obtained in this study formed a separate monophyletic branch with clade 5, indicating it to be evolved from a distinct ancestor. The nucleotide-based analysis revealed 13 different SNP mutations and one multiple nucleotide variation in the VZV sequences when compared to one of the clade 5 genomes having accession number: DQ457052.1. Interpretation & conclusions: The present study described approximately 98 per cent of the genome sequence of VZV from India. The availability of these genomic sequences will lead to enrichment in the clinical genomic data set from India. The available data would help in the development of diagnostic methods along with evolutionary analysis. We hypothesize the existence of a new sub-clade that belongs to clade 5 and propose further experiments to confirm these results.


Asunto(s)
Herpes Zóster , Herpesvirus Humano 3 , Humanos , Genoma Viral/genética , Genotipo , Herpes Zóster/epidemiología , Herpes Zóster/genética , Herpesvirus Humano 3/genética , Filogenia , Polimorfismo de Nucleótido Simple
4.
J Virol ; 93(13)2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30971476

RESUMEN

In 2011, ticks were collected from livestock following an outbreak of Crimean Congo hemorrhagic fever (CCHF) in Gujarat state, India. CCHF-negative Hyalomma anatolicum tick pools were passaged for virus isolation, and two virus isolates were obtained, designated Karyana virus (KARYV) and Kundal virus (KUNDV), respectively. Traditional reverse transcription-PCR (RT-PCR) identification of known viruses was unsuccessful, but a next-generation sequencing (NGS) approach identified KARYV and KUNDV as viruses in the Reoviridae family, Orbivirus and Coltivirus genera, respectively. Viral genomes were de novo assembled, yielding 10 complete segments of KARYV and 12 nearly complete segments of KUNDV. The VP1 gene of KARYV shared a most recent common ancestor with Wad Medani virus (WMV), strain Ar495, and based on nucleotide identity we demonstrate that it is a novel WMV strain. The VP1 segment of KUNDV shares a common ancestor with Colorado tick fever virus, Eyach virus, Tai Forest reovirus, and Tarumizu tick virus from the Coltivirus genus. Based on VP1, VP6, VP7, and VP12 nucleotide and amino acid identities, KUNDV is proposed to be a new species of Coltivirus Electron microscopy supported the classification of KARYV and KUNDV as reoviruses and identified replication morphology consistent with other orbi- and coltiviruses. The identification of novel tick-borne viruses carried by the CCHF vector is an important step in the characterization of their potential role in human and animal pathogenesis.IMPORTANCE Ticks and mosquitoes, as well Culicoides, can transmit viruses in the Reoviridae family. With the help of next-generation sequencing (NGS), previously unreported reoviruses such as equine encephalosis virus, Wad Medani virus (WMV), Kammavanpettai virus (KVPTV), and, with this report, KARYV and KUNDV have been discovered and characterized in India. The isolation of KUNDV and KARYV from Hyalomma anatolicum, which is a known vector for zoonotic pathogens, such as Crimean Congo hemorrhagic fever virus, Babesia, Theileria, and Anaplasma species, identifies arboviruses with the potential to transmit to humans. Characterization of KUNDV and KARYV isolated from Hyalomma ticks is critical for the development of specific serological and molecular assays that can be used to determine the association of these viruses with disease in humans and livestock.


Asunto(s)
Coltivirus/clasificación , Coltivirus/aislamiento & purificación , Virus de la Fiebre Hemorrágica de Crimea-Congo/aislamiento & purificación , Fiebre Hemorrágica de Crimea/complicaciones , Orbivirus/clasificación , Orbivirus/aislamiento & purificación , Filogenia , Garrapatas/virología , Animales , Chlorocebus aethiops , Coltivirus/genética , Culicidae/virología , Genoma Viral , Virus de la Fiebre Hemorrágica de Crimea-Congo/clasificación , Virus de la Fiebre Hemorrágica de Crimea-Congo/genética , Fiebre Hemorrágica de Crimea/epidemiología , Fiebre Hemorrágica de Crimea/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , India , Mosquitos Vectores/virología , Orbivirus/genética , Reoviridae/clasificación , Reoviridae/genética , Reoviridae/aislamiento & purificación , Reoviridae/ultraestructura , Células Vero , Ensayo de Placa Viral , Proteínas Virales/genética
5.
Indian J Med Res ; 151(6): 571-577, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32719230

RESUMEN

Background & objectives: The presence of Cat Que virus (CQV) in Culex mosquitoes and pigs has been reported in China and Vietnam. Due to the spread of similar species of the Culex mosquitoes in India, there is a need to understand the replication kinetics of this virus in mosquito models. As a part of preparedness and to identify the presence of this CQV in humans and swine, this study was carried out to develop diagnostic tests. Methods: Serological and molecular diagnostic assays were developed for testing the mosquito population, human and swine serum samples. In this line, RNA-dependent RNA polymerase (L), glycoprotein (M) and nucleocapsid (S) genes-based reverse transcription-polymerase chain reaction (RT-PCR) assays were developed for CQV. Real-time RT-PCR was used for screening of retrospectively collected human serum samples (n=1020) with acute febrile illness during 2014-2017. Simultaneously, an in-house anti-CQV swine and human IgG ELISAs were also developed to detect anti-CQV IgG antibody. Human serum samples (n=883) with post-onset of disease (POD) >4 days and swine serum samples (n=459) were tested for the presence of anti-CQV IgG antibodies. CQV NIV 612,045 isolate was used for susceptibility and replication kinetics experiment using three different species of mosquitoes to understand its behaviour in Indian mosquitoes. Results: All human serum samples (n=1020) screened for the presence of CQV using real-time RT-PCR were found to be negative. Anti-CQV IgG antibody positivity was recorded in two of 883 human serum samples tested. Virus susceptibility experiments indicated that three species of mosquito, namely Aedes aegypti, Culex quinquefasciatus and Cx. tritaeniorhynchus supported multiplication of CQV by intrathoracic as well as artificial membrane/oral feeding routes. Interpretation & conclusions: Anti-CQV IgG antibody positivity in human serum samples tested and the replication capability of CQV in mosquitoes indicated a possible disease causing potential of CQV in Indian scenario. Screening of more human and swine serum samples using these assays is required as a proactive measure for understanding the prevalence of this neglected tropical virus.


Asunto(s)
Aedes , Culex , Orthobunyavirus , Animales , China , India/epidemiología , Estudios Retrospectivos , Porcinos
6.
Indian J Med Res ; 152(1 & 2): 70-76, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32773420

RESUMEN

BACKGROUND & OBJECTIVES: The genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), belonging to the family Coronaviridae, encodes for structural, non-structural, and accessory proteins, which are required for replication of the virus. These proteins are encoded by different genes present on the SARS-CoV-2 genome. The expression pattern of these genes in the host cells needs to be assessed. This study was undertaken to understand the transcription pattern of the SARS-CoV-2 genes in the Vero CCL-81 cells during the course of infection. METHODS: Vero CCL-81 cells were infected with the SARS-CoV-2 virus inoculum having a 0.1 multiplicity of infection. The supernatants and cell pellets were harvested after centrifugation at different time points, post-infection. The 50% tissue culture infective dose (TCID50)and cycle threshold (Ct) values of the E and the RdRp-2 genes were calculated. Next-generation sequencing of the harvested sample was carried out to observe the expression pattern of the virus by mapping to the SARS-CoV-2 Wuhan HU-1 reference sequence. The expressions were in terms of the reads per kilobase million (RPKM) values. RESULTS: In the inital six hours post-infection, the copy numbers of E and RdRp-2 genes were approximately constant, which raised 10 log-fold and continued to increase till the 12 h post-infection (hpi). The TCID50 was observed in the supernatant after 7 hpi, indicating the release of the viral progeny. ORF8 and ORF7a, along with the nucleocapsid transcript, were found to express at higher levels. INTERPRETATION & CONCLUSIONS: This study was a step towards understanding the growth kinetics of the SARS-CoV-2 replication cycle. The findings indicated that ORF8 and ORF7b gene transcripts were expressed in higher amounts indicating their essential role in viral replication. Future studies need to be conducted to explore their role in the SARS-CoV-2 replication.


Asunto(s)
Betacoronavirus/genética , Infecciones por Coronavirus/genética , Neumonía Viral/genética , Transcriptoma/genética , Animales , Betacoronavirus/patogenicidad , COVID-19 , Chlorocebus aethiops , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/virología , Humanos , Pandemias , Neumonía Viral/patología , Neumonía Viral/virología , SARS-CoV-2 , Células Vero/virología , Replicación Viral/genética
7.
Indian J Med Res ; 151(2 & 3): 200-209, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32242873

RESUMEN

Background & objectives: Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has globally affected 195 countries. In India, suspected cases were screened for SARS-CoV-2 as per the advisory of the Ministry of Health and Family Welfare. The objective of this study was to characterize SARS-CoV-2 sequences from three identified positive cases as on February 29, 2020. Methods: Throat swab/nasal swab specimens for a total of 881 suspected cases were screened by E gene and confirmed by RdRp (1), RdRp (2) and N gene real-time reverse transcription-polymerase chain reactions and next-generation sequencing. Phylogenetic analysis, molecular characterization and prediction of B- and T-cell epitopes for Indian SARS-CoV-2 sequences were undertaken. Results: Three cases with a travel history from Wuhan, China, were confirmed positive for SARS-CoV-2. Almost complete (29,851 nucleotides) genomes of case 1, case 3 and a fragmented genome for case 2 were obtained. The sequences of Indian SARS-CoV-2 though not identical showed high (~99.98%) identity with Wuhan seafood market pneumonia virus (accession number: NC 045512). Phylogenetic analysis showed that the Indian sequences belonged to different clusters. Predicted linear B-cell epitopes were found to be concentrated in the S1 domain of spike protein, and a conformational epitope was identified in the receptor-binding domain. The predicted T-cell epitopes showed broad human leucocyte antigen allele coverage of A and B supertypes predominant in the Indian population. Interpretation & conclusions: The two SARS-CoV-2 sequences obtained from India represent two different introductions into the country. The genetic heterogeneity is as noted globally. The identified B- and T-cell epitopes may be considered suitable for future experiments towards the design of vaccines and diagnostics. Continuous monitoring and analysis of the sequences of new cases from India and the other affected countries would be vital to understand the genetic evolution and rates of substitution of the SARS-CoV-2.


Asunto(s)
Betacoronavirus/genética , Genoma Viral , COVID-19 , Infecciones por Coronavirus , Epítopos de Linfocito B/genética , Epítopos de Linfocito T/genética , Humanos , India , Modelos Moleculares , Pandemias , Filogenia , Neumonía Viral , Estructura Terciaria de Proteína , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/genética
8.
Indian J Med Res ; 151(2 & 3): 226-235, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32317409

RESUMEN

Background & objectives: Bats are considered to be the natural reservoir for many viruses, of which some are potential human pathogens. In India, an association of Pteropus medius bats with the Nipah virus was reported in the past. It is suspected that the recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also has its association with bats. To assess the presence of CoVs in bats, we performed identification and characterization of bat CoV (BtCoV) in P. medius and Rousettus species from representative States in India, collected during 2018 and 2019. Methods: Representative rectal swab (RS) and throat swab specimens of Pteropus and Rousettus spp. bats were screened for CoVs using a pan-CoV reverse transcription-polymerase chain reaction (RT-PCR) targeting the RNA-dependent RNA polymerase (RdRp) gene. A single-step RT-PCR was performed on the RNA extracted from the bat specimens. Next-generation sequencing (NGS) was performed on a few representative bat specimens that were tested positive. Phylogenetic analysis was carried out on the partial sequences of RdRp gene sequences retrieved from both the bat species and complete viral genomes recovered from Rousettus spp. Results: Bat samples from the seven States were screened, and the RS specimens of eight Rousettus spp. and 21 Pteropus spp. were found positive for CoV RdRp gene. Among these, by Sanger sequencing, partial RdRp sequences could be retrieved from three Rousettus and eight Pteropus bat specimens. Phylogenetic analysis of the partial RdRp region demonstrated distinct subclustering of the BtCoV sequences retrieved from these Rousettus and Pteropus spp. bats. NGS led to the recovery of four sequences covering approximately 94.3 per cent of the whole genome of the BtCoVs from Rousettus bats. Three BtCoV sequences had 93.69 per cent identity to CoV BtRt-BetaCoV/GX2018. The fourth BtCoV sequence was 96.8 per cent identical to BtCoV HKU9-1. Interpretation & conclusions: This study was a step towards understanding the CoV circulation in Indian bats. Detection of potentially pathogenic CoVs in Indian bats stresses the need for enhanced screening for novel viruses in them. One Health approach with collaborative activities by the animal health and human health sectors in these surveillance activities shall be of use to public health. This would help in the development of diagnostic assays for novel viruses with outbreak potential and be useful in disease interventions. Proactive surveillance remains crucial for identifying the emerging novel viruses with epidemic potential and measures for risk mitigation.


Asunto(s)
Quirópteros/virología , Coronavirus/clasificación , Coronavirus/aislamiento & purificación , Genoma Viral , Animales , Secuenciación de Nucleótidos de Alto Rendimiento , India , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
Indian J Med Res ; 151(5): 444-449, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32611915

RESUMEN

BACKGROUND & OBJECTIVES: Since the beginning of the year 2020, the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impacted humankind adversely in almost all spheres of life. The virus belongs to the genus Betacoronavirus of the family Coronaviridae. SARS-CoV-2 causes the disease known as coronavirus disease 2019 (COVID-19) with mild-to-severe respiratory illness. The currently available diagnostic tools for the diagnosis of COVID-19 are mainly based on molecular assays. Real-time reverse transcription-polymerase chain reaction is the only diagnostic method currently recommended by the World Health Organization for COVID-19. With the rapid spread of SARS-CoV-2, it is necessary to utilize other tests, which would determine the burden of the disease as well as the spread of the outbreak. Considering the need for the development of such a screening test, an attempt was made to develop and evaluate an IgG-based ELISA for COVID-19. METHODS: A total of 513 blood samples (131 positive, 382 negative for SARS-CoV-2) were collected and tested by microneutralization test (MNT). Antigen stock of SARS-CoV-2 was prepared by propagating the virus in Vero CCL-81 cells. An IgG capture ELISA was developed for serological detection of anti-SARS-CoV-2 IgG in serum samples. The end point cut-off values were determined by using receiver operating characteristic (ROC) curve. Inter-assay variability was determined. RESULTS: The developed ELISA was found to be 92.37 per cent sensitive, 97.9 per cent specific, robust and reproducible. The positive and negative predictive values were 94.44 and 98.14 per cent, respectively. INTERPRETATION & CONCLUSIONS: This indigenously developed IgG ELISA was found to be sensitive and specific for the detection of anti-SARS-CoV-2 IgG in human serum samples. This assay may be used for determining seroprevalence of SARS-CoV-2 in a population exposed to the virus.


Asunto(s)
Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/epidemiología , Inmunoglobulina G/sangre , Neumonía Viral/sangre , Neumonía Viral/epidemiología , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Humanos , India/epidemiología , Pandemias , Neumonía Viral/diagnóstico , Valor Predictivo de las Pruebas , Prevalencia , Curva ROC , Reproducibilidad de los Resultados , SARS-CoV-2 , Estudios Seroepidemiológicos
10.
Indian J Med Res ; 150(2): 186-193, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31670274

RESUMEN

Background & objectives: Kyasanur forest disease (KFD) is an infectious disease discovered in Karnataka State of India in 1957; since then, the State has been known to be enzootic for KFD. In the last few years, its presence was observed in the adjoining five States of the Western Ghats of India. The present study was conducted to understand the kinetics of viral RNA, immunoglobulin M (IgM) and IgG antibody in KFD-infected humans for developing a diagnostic algorithm for KFD. Methods: A prospective follow up study was performed among KFD patients in Sindhudurg district of Maharashtra State, India. A total of 1046 suspected patients were tested, and 72 KFD patients were enrolled and followed for 17 months (January 2016 to May 2017). Serum samples of KFD patients were screened for viral RNA, and IgM and IgG antibodies. Results: KFD viral positivity was observed from 1st to 18th post-onset day (POD). Positivity of anti-KFD virus (KFDV) IgM antibodies was detected from 4th till 122nd POD and anti-KFDV IgG antibodies detected from 5th till 474th POD. A prediction probability was determined from statistical analysis using the generalized additive model in R-software to support the laboratory findings regarding viral kinetics. Interpretation & conclusions: This study demonstrated the presence of KFD viral RNA till 18th POD, IgM antibodies till 122nd POD and IgG till the last sample collected. Based on our study an algorithm was recommended for accurate laboratory diagnosis of KFDV infection. A sample collected between 1 and 3 POD can be tested using KFDV real-time reverse transcriptase polymerase chain reaction (RT-PCR); between 4 and 24 POD, the combination of real-time RT-PCR and anti-KFDV IgM enzyme-linked immunosorbent assay (ELISA) tests can be used; between POD 25 and 132, anti-KFDV IgM and IgG ELISA are recommended.


Asunto(s)
Anticuerpos Antivirales/sangre , Ensayo de Inmunoadsorción Enzimática , Enfermedad del Bosque de Kyasanur/sangre , ARN Viral/química , Anticuerpos/sangre , Anticuerpos Antivirales/química , Brotes de Enfermedades , Virus de la Encefalitis Transmitidos por Garrapatas/aislamiento & purificación , Virus de la Encefalitis Transmitidos por Garrapatas/patogenicidad , Femenino , Humanos , Inmunoglobulina G/química , Inmunoglobulina G/genética , Inmunoglobulina M/química , Inmunoglobulina M/genética , Cinética , Enfermedad del Bosque de Kyasanur/genética , Enfermedad del Bosque de Kyasanur/virología , Masculino , ARN Viral/genética
12.
Indian J Med Res ; 147(1): 88-96, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29749366

RESUMEN

BACKGROUND & OBJECTIVES: There are reports about the susceptibility of Aedes mosquitoes to ZIKV from various countries, however, no such information is available from Indian sub-continent, although, high level of group cross-reactivity of ZIKV with other flaviviruses has been reported. During outbreak situations, many cases of Dengue (DEN) and Chikungunya (CHIK) are reported. In such scenario, vector mosquitoes are likely to get co-infection/secondary-infection with one or other virus. The present study was carried out to determine the susceptibility of Indian strain of Aedes aegypti to Zika virus (ZIKV) strain (MR-766) and the effect of co-infection/super-infection with either dengue virus (serotype-2) (DENV) or chikungunya virus (CHIKV) on ZIKV replication. METHODS: Ae. aegypti mosquitoes used in this study were reared for many generations since 1980 at laboratory colony maintained at the ICMR-National Institute of Virology, Pune, India. Transmissibility of ZIKV from infected mosquitoes to suckling mice was also studied. Mosquitoes were experimentally infected with ZIKV and super-infected with either DENV or CHIKV via membrane-feeding route and incubated for 14 days at 28±2°C and humidity of 85±5 per cent. Replication of these viruses in mosquitoes was confirmed using real-time reverse transcription-polymerase chain reaction and immunofluorescence assay. Twenty infected mosquitoes were allowed to feed upon four suckling CD1 mice for about 30 min. Transmission of the ZIKV by infected mosquitoes to suckling mice was confirmed by the appearance of clinical signs and the presence of viral RNA in different organs. RESULTS: Concomitant infection of mosquitoes with all the three viruses showed simultaneous propagation of all three viruses, confirmed by real time RT-PCR and IFA. Infection of mosquitoes with CHIKV followed by ZIKV showed positivity in individual head squashes (7%) for both viruses using IFA; only 8.3 per cent showed dual positivity with primary infection of ZIKV followed by DENV; 8.3 per cent dual infection positivity was observed when infected with DENV followed by ZIKV; 5 per cent showed dual infection was observed when infected with ZIKV followed by CHIKV. Ae. aegypti was found to be susceptible to ZIKV strain as ZIKV could be detected from the second post-infection day (PID) in infected mosquitoes. Transmission of ZIKV to mice by the bite of infected Ae. aegypti establishes this species as a potential vector. INTERPRETATION & CONCLUSIONS: From super-infection experiments, it was concluded that ZIKV might have a relative advantage in replication dynamics over DENV. Vertical transmission was not observed for ZIKV in experimentally infected mosquitoes (n=920 larvae). Further studies are required to understand the possibility of silently circulating ZIKV in India, which remain non-detected because of lack of surveillance.


Asunto(s)
Fiebre Chikungunya/virología , Coinfección/virología , Dengue/virología , Infección por el Virus Zika/virología , Animales , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/transmisión , Virus Chikungunya/patogenicidad , Coinfección/epidemiología , Coinfección/transmisión , Dengue/epidemiología , Dengue/transmisión , Virus del Dengue/patogenicidad , Densovirinae , Brotes de Enfermedades , Humanos , India/epidemiología , Larva/virología , Mosquitos Vectores/virología , Replicación Viral/genética , Virus Zika/patogenicidad , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/transmisión
13.
Intervirology ; 60(6): 227-234, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29597193

RESUMEN

OBJECTIVES: The objective of this study was to understand natural disease progression in infant CD1 mice after the bite of Aedes aegypti mosquitoes infected by the Zika virus (ZIKV, MR-766 strain). METHODS: A. aegypti mosquitoes were experimentally infected with ZIKV MR-766 strain via the oral feeding route. Infected mosquitoes were allowed to feed on infant CD1 mice. Sick mice were euthanized, and their organs were collected and subjected to real-time RT-PCR, histo-pathology, and immunohistochemistry. RESULTS: Clinical symptoms appeared in mice after 4-5 days of being bitten by mosquitoes, following which they were euthanized. Real-time RT-PCR analysis showed the presence of viral RNA in various organs such as the brain, liver, kidney, spleen, lungs, and intestines of the mice. The brain tissue specimens showed higher viral loads as determined by threshold values (Ct value) in the real-time RT-PCR assay. Histopathological and immunohistochemistry studies also revealed the presence of the virus and associated lesions in the brain, indicating that ZIKV shows tropism for neuronal tissue. CONCLUSIONS: This study demonstrates ZIKV pathogenesis in infant CD1 mice and that these mice are highly susceptible to natural infection with this ZIKV strain.

16.
Emerg Infect Dis ; 21(10): 1837-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26402332

RESUMEN

We conducted a cross-sectional serosurvey of Crimean-Congo hemorrhagic fever (CCHF) among livestock in 22 states and 1 union territory of India. A total of 5,636 samples from bovines, sheep, and goats were screened for CCHF virus IgG. IgG was detected in 354 samples, indicating that this virus is widespread in this country.


Asunto(s)
Reservorios de Enfermedades/virología , Fiebre Hemorrágica de Crimea/epidemiología , Ganado/virología , Animales , Anticuerpos Antivirales/sangre , Bovinos/virología , Estudios Transversales , Cabras/virología , Virus de la Fiebre Hemorrágica de Crimea-Congo/inmunología , Fiebre Hemorrágica de Crimea/veterinaria , Inmunoglobulina G , India/epidemiología , Estudios Seroepidemiológicos , Ovinos/virología
19.
Indian J Med Res ; 140(2): 171-83, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25297350

RESUMEN

Since the enactment of Environmental Protection Act in 1989 and Department of Biotechnology (DBT) guidelines to deal with genetically modified organisms, India has embarked on establishing various levels of biosafety laboratories to deal with highly infectious and pathogenic organisms. Occurrence of outbreaks due to rapidly spreading respiratory and haemorrhagic fever causing viruses has caused an urgency to create a safe laboratory environment. This has thus become a mandate, not only to protect laboratory workers, but also to protect the environment and community. In India, technology and science are progressing rapidly. Several BSL-3 [=high containment] laboratories are in the planning or execution phase, to tackle biosafety issues involved in handling highly infectious disease agents required for basic research and diagnosis. In most of the developing countries, the awareness about biocontainment has increased but planning, designing, constructing and operating BSL-3 laboratories need regular updates about the design and construction of facilities and clear definition of risk groups and their handling which should be in harmony with the latest international practices. This article describes the major steps involved in the process of construction of a BSL-3 laboratory in Indian settings, from freezing the concept of proposal to operationalization phase. The key to success of this kind of project is strong institutional commitment to biosafety norms, adequate fund availability, careful planning and designing, hiring good construction agency, monitoring by experienced consultancy agency and involvement of scientific and engineering personnel with biocontainment experience in the process.


Asunto(s)
Contención de Riesgos Biológicos , Arquitectura y Construcción de Instituciones de Salud/métodos , Arquitectura y Construcción de Instituciones de Salud/normas , Laboratorios/organización & administración , Laboratorios/normas , Seguridad/normas , India
20.
Ann Med ; 55(2): 2253733, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37672487

RESUMEN

BACKGROUND: The multi-country mpox outbreak across the globe has led to the systematic surveillance of mpox cases in India. During the surveillance of mpox, we encountered cases of Varicella Zoster Virus (VZV) in suspected mpox cases amongst children & adults. This study focused on the genomic characterization of VZV in India. METHODS: A total of 331 mpox suspected cases were tested for VZV through real-time PCR, and the positive samples were subjected to next-generation sequencing to retrieve the whole genome of VZV using CLC genomics software. Phylogenetic analysis has been done in MEGA 11.0 software to identify circulating clades. RESULT: Of the 331 suspected cases, 28 cases with vesicular rashes were found to be positive for VZV. The maximum genome could be retrieved from the clinical specimens of 16 cases with coverage greater than 98% when mapped with reference strain Dumas (NC 001348). The phylogenetic analyses of these sequences determined the circulation of clades 1, 5, and 9 in India. Further, the sequence analysis demonstrated non-synonymous single nucleotide polymorphism (SNPs) among specific ORF of VZV including ORF 14, ORF 22, ORF 36, ORF 37 and ORF 51. Although clade 1 and 5 has been reported earlier, the circulation of clade 9 of VZV has been determined for the first time in India. CONCLUSION: Although the circulation of different clades of VZV was reported from India, the presence of clade 9 was detected for the first time during the mpox surveillance.


Asunto(s)
Herpesvirus Humano 3 , Mpox , Adulto , Niño , Humanos , Herpesvirus Humano 3/genética , Filogenia , Genómica , India/epidemiología
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