We report the development of a triplex nucleic acid lateral flow immunoassay(NALFIA)for the detection of the genomes of Nipah virus(NiV),Middle East respiratory syndrome coronavirus(MERS-CoV)and Reston ebolavirus(REBO...We report the development of a triplex nucleic acid lateral flow immunoassay(NALFIA)for the detection of the genomes of Nipah virus(NiV),Middle East respiratory syndrome coronavirus(MERS-CoV)and Reston ebolavirus(REBOV),which are intended for screening bats as well as other hosts and reservoirs of these three viruses.Our triplex NALFIA is a two-step assay format:the target nucleic acid in the sample is first amplified using tagged primers,and the tagged dsDNA amplicons are captured by antibodies immobilized on the NALFIA device,resulting in signal development from the binding of a streptavidin-colloidal gold conjugate to a biotin tag on the captured amplicons.Triplex amplification of the N gene of NiV,the UpE gene of MERS-CoV,and the Vp40 gene of REBOV was optimized,and three compatible combinations of hapten labels and antibodies were identified for end point detection.The lowest RNA copy numbers detected by the triplex NALFIA were 8.21e4 for the NiV N target,7.09e1 for the MERS-CoV UpE target,and 1.83e4 for the REBOV Vp40 target.Using simulated samples,the sensitivity and specificity for MERS-CoV and REBOV targets were estimated to be 100%,while the sensitivity and specificity for the NiV target were 91%and 93.3%,respectively.The compliance rate between triplex NALFIA and real-time RT‒PCR was 92%for the NiV N target and 100%for the MERS-CoV UpE and REBOV Vp40 targets.展开更多
Nipah virus (NiV), a zoonotic paramyxovirus belonging to the genus Henipavirus, is classified as a Biosafety Level-4 pathogen based on its high pathogenicity in humans and the lack of available vaccines or therapeutic...Nipah virus (NiV), a zoonotic paramyxovirus belonging to the genus Henipavirus, is classified as a Biosafety Level-4 pathogen based on its high pathogenicity in humans and the lack of available vaccines or therapeutics. Since its initial emergence in 1998 in Malaysia, this virus has become a great threat to domestic animals and humans. Sporadic outbreaks and person-to-person transmission over the past two decades have resulted in hundreds of human fatalities. Epidemiological surveys have shown that NiV is distributed in Asia, Africa, and the South Pacific Ocean, and is transmitted by its natural reservoir, Pteropid bats. Numerous efforts have been made to analyze viral protein function and structure to develop feasible strategies for drug design. Increasing surveillance and preventative measures for the viral infectious disease are urgently needed.展开更多
Nipah virus(Ni V)is a member of the genus Henipavirus of the family Paramyxoviridae,characterized by high pathogenicity and endemic in South Asia.It is classified as a Biosafety Level-4(BSL-4)agent.The case-fatality v...Nipah virus(Ni V)is a member of the genus Henipavirus of the family Paramyxoviridae,characterized by high pathogenicity and endemic in South Asia.It is classified as a Biosafety Level-4(BSL-4)agent.The case-fatality varies from 40%-70%depending on the severity of the disease and on the availability of adequate healthcare facilities.At present no antiviral drugs are available for Ni V disease and the treatment is just supportive.Phylogenetic and evolutionary analyses can be used to help in understanding the epidemiology and the temporal origin of this virus.This review provides an overview of evolutionary studies performed on Nipah viruses circulating in different countries.Thirty phylogenetic studies have been published from 2000 to 2015 years,searching on pub-med using the key words‘Nipah virus AND phylogeny'and twenty-eight molecular epidemiological studies from 2006 to 2015 have been performed,typing the key words‘Nipah virus AND molecular epidemiology'.Overall data from the published study demonstrated as phylogenetic and evolutionary analysis represent promising tools to evidence NiV epidemics,to study their origin and evolution and finally to act with effective preventive measure.展开更多
Nipah virus(NiV)is a zoonotic paramyxovirus in the genus Henipavirus that is prevalent in Southeast Asia.NiV leads to severe respiratory disease and encephalitis in humans and animals,with a mortality rate of up to 75...Nipah virus(NiV)is a zoonotic paramyxovirus in the genus Henipavirus that is prevalent in Southeast Asia.NiV leads to severe respiratory disease and encephalitis in humans and animals,with a mortality rate of up to 75%.Despite the grave threat to public health and global biosecurity,no medical countermeasures are available for humans.Here,based on self-assembled ferritin nanoparticles(FeNPs),we successfully constructed two candidate FeNP vaccines by loading mammalian cells expressing NiV sG(residues 71–602,FeNP-sG)and Ghead(residues 182–602,FeNP-Ghead)onto E.coli-expressed FeNPs(FeNP-sG and FeNP-Ghead,respectively)through Spycatcher/Spytag technology.Compared with sG and Ghead alone,FeNP-sG and FeNP-Ghead elicited significant NiV specific neutralizing antibody levels and T-cell responses in mice,whereas the immune response in the FeNP-sG immunized group was greater than that in the FeNP-Ghead group.These results further demonstrate that sG possesses greater antigenicity than Ghead and that FeNPs can dramatically enhance immunogenicity.Furthermore,FeNP-sG provided 100%protection against NiV challenge in a hamster model when it was administered twice at a dose of 5μg/per animal.Our study provides not only a promising candidate vaccine against NiV,but also a theoretical foundation for the design of a NiV immunogen for the development of novel strategies against NiV infection.展开更多
The optimal use of intervention strategies to mitigate the spread of Nipah Virus (NiV) using optimal control technique is studied in this paper. First of all we formulate a dynamic model of NiV infections with variabl...The optimal use of intervention strategies to mitigate the spread of Nipah Virus (NiV) using optimal control technique is studied in this paper. First of all we formulate a dynamic model of NiV infections with variable size population and two control strategies where creating awareness and treatment are considered as controls. We intend to find the optimal combination of these two control strategies that will minimize the cost of the two control measures and as a result the number of infectious individuals will decrease. We establish the existence for the optimal controls and Pontryagin’s maximum principle is used to characterize the optimal controls. The numerical simulation suggests that optimal control technique is much more effective to minimize the infected individuals and the corresponding cost of the two controls. It is also monitored that in the case of high contact rate, controls have to work for longer period of time to get the desired result. Numerical simulation reveals that the spread of Nipah virus can be controlled effectively if we apply control strategy at early stage.展开更多
Objective: To explore a common B-and T-cell epitope-based vaccine that can elicit an immune response against encephalitis causing genus Henipaviruses, Hendra virus(He V) and Nipah virus(Ni V). Methods: Membrane protei...Objective: To explore a common B-and T-cell epitope-based vaccine that can elicit an immune response against encephalitis causing genus Henipaviruses, Hendra virus(He V) and Nipah virus(Ni V). Methods: Membrane proteins F, G and M of He V and Ni V were retrieved from the protein database and subjected to different bioinformatics tools to predict antigenic B-cell epitopes. Best B-cell epitopes were then analyzed to predict their T-cell antigenic potentiality. Antigenic B-and T-cell epitopes that shared maximum identity with He V and Ni V were selected. Stability of the selected epitopes was predicted. Finally, the selected epitopes were subjected to molecular docking simulation with HLA-DR to confirm their antigenic potentiality in silico. Results: One epitope from G proteins, one from M proteins and none from F proteins were selected based on their antigenic potentiality. The epitope from the G proteins was stable whereas that from M was unstable. The M-epitope was made stable by adding flanking dipeptides. The 15-mer G-epitope(VDPLRVQWRNNSVIS) showed at least 66% identity with all Ni V and He V G protein sequences, while the 15-mer M-epitope(GKLEFRRNNAIAFKG) with the dipeptide flanking residues showed 73% identity with all Ni V and He V M protein sequences available in the database. Molecular docking simulation with most frequent MHC class-II(MHC II) and class-I(MHC I) molecules showed that these epitopes could bind within HLA binding grooves to elicit an immune response. Conclusions: Data in our present study revealed the notion that the epitopes from G and M proteins might be the target for peptide-based subunit vaccine design against He V and Ni V. However, the biochemical analysis is necessary to experimentally validate the interaction of epitopes individually with the MHC molecules through elucidation of immunity induction.展开更多
Dear editor, In India, it is high time to focus on one health approach to address the emerging/reemerging disease. The fight between microbe and man influence the inexorable archenemy that needs to be dealt. Since Sec...Dear editor, In India, it is high time to focus on one health approach to address the emerging/reemerging disease. The fight between microbe and man influence the inexorable archenemy that needs to be dealt. Since Second World War, there has been an average increase in emergence or reemergence of new diseases particularly from an animal source (75%)(1)India is identified as a major hotspot area for infectious diseases in South Asia regarding zoonoses(2)As this emergence of India as a Zoonotic hotspot, the consequence of it to further on other region and global health raises queries to global preparedness concerning epidemic potential.展开更多
Objective:To establish Nipah virus diagnostic capabilities at the National Reference Laboratory in Sri Lanka using the NIV Pune real-time PCR kit.Methods:Strict safety precautions were adhered during testing due to th...Objective:To establish Nipah virus diagnostic capabilities at the National Reference Laboratory in Sri Lanka using the NIV Pune real-time PCR kit.Methods:Strict safety precautions were adhered during testing due to the high pathogenicity of the Nipah virus,with all diagnostics conducted in a BSL2+laboratory at the Medical Research Institute in Sri Lanka.RNA extraction was performed using the QIAamp Viral RNA Mini kit.The NIV Pune in-house real-time PCR kit was employed,following established primer/probe sequences and controls.The assay was validated using the Rotor-Gene Q Series Real-time PCR platform.Results:The validation run of the Nipah virus real-time PCR test demonstrated robust performance,with positive controls consistently detecting Nipah RNA at a Ct value of 21.50±0.01.Negative controls confirmed assay specificity with an external negative control which was also used as an extraction control and showed no interference.The internal control exhibited stable behavior,enhancing confidence in PCR results.The qPCR analysis graph illustrated the successful detection of internal and positive controls,validating the reliability of the assay.Conclusions:Establishing Nipah virus diagnostic capabilities in Sri Lanka signifies a proactive and collaborative response to the persistent global health threat.展开更多
基金funded by the Department of Biotechnology,Ministry of Science and Technology,Government of India(DBT)under grant number ADMaC DBT-NER/LIVS/11/2012.
文摘We report the development of a triplex nucleic acid lateral flow immunoassay(NALFIA)for the detection of the genomes of Nipah virus(NiV),Middle East respiratory syndrome coronavirus(MERS-CoV)and Reston ebolavirus(REBOV),which are intended for screening bats as well as other hosts and reservoirs of these three viruses.Our triplex NALFIA is a two-step assay format:the target nucleic acid in the sample is first amplified using tagged primers,and the tagged dsDNA amplicons are captured by antibodies immobilized on the NALFIA device,resulting in signal development from the binding of a streptavidin-colloidal gold conjugate to a biotin tag on the captured amplicons.Triplex amplification of the N gene of NiV,the UpE gene of MERS-CoV,and the Vp40 gene of REBOV was optimized,and three compatible combinations of hapten labels and antibodies were identified for end point detection.The lowest RNA copy numbers detected by the triplex NALFIA were 8.21e4 for the NiV N target,7.09e1 for the MERS-CoV UpE target,and 1.83e4 for the REBOV Vp40 target.Using simulated samples,the sensitivity and specificity for MERS-CoV and REBOV targets were estimated to be 100%,while the sensitivity and specificity for the NiV target were 91%and 93.3%,respectively.The compliance rate between triplex NALFIA and real-time RT‒PCR was 92%for the NiV N target and 100%for the MERS-CoV UpE and REBOV Vp40 targets.
基金supported by National Key Research and Development Program(2016YFC1200800)Advanced Customer Cultivation Project of Wuhan National Biosafety Laboratory,Chinese Academy of Sciences
文摘Nipah virus (NiV), a zoonotic paramyxovirus belonging to the genus Henipavirus, is classified as a Biosafety Level-4 pathogen based on its high pathogenicity in humans and the lack of available vaccines or therapeutics. Since its initial emergence in 1998 in Malaysia, this virus has become a great threat to domestic animals and humans. Sporadic outbreaks and person-to-person transmission over the past two decades have resulted in hundreds of human fatalities. Epidemiological surveys have shown that NiV is distributed in Asia, Africa, and the South Pacific Ocean, and is transmitted by its natural reservoir, Pteropid bats. Numerous efforts have been made to analyze viral protein function and structure to develop feasible strategies for drug design. Increasing surveillance and preventative measures for the viral infectious disease are urgently needed.
文摘Nipah virus(Ni V)is a member of the genus Henipavirus of the family Paramyxoviridae,characterized by high pathogenicity and endemic in South Asia.It is classified as a Biosafety Level-4(BSL-4)agent.The case-fatality varies from 40%-70%depending on the severity of the disease and on the availability of adequate healthcare facilities.At present no antiviral drugs are available for Ni V disease and the treatment is just supportive.Phylogenetic and evolutionary analyses can be used to help in understanding the epidemiology and the temporal origin of this virus.This review provides an overview of evolutionary studies performed on Nipah viruses circulating in different countries.Thirty phylogenetic studies have been published from 2000 to 2015 years,searching on pub-med using the key words‘Nipah virus AND phylogeny'and twenty-eight molecular epidemiological studies from 2006 to 2015 have been performed,typing the key words‘Nipah virus AND molecular epidemiology'.Overall data from the published study demonstrated as phylogenetic and evolutionary analysis represent promising tools to evidence NiV epidemics,to study their origin and evolution and finally to act with effective preventive measure.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0490000).
文摘Nipah virus(NiV)is a zoonotic paramyxovirus in the genus Henipavirus that is prevalent in Southeast Asia.NiV leads to severe respiratory disease and encephalitis in humans and animals,with a mortality rate of up to 75%.Despite the grave threat to public health and global biosecurity,no medical countermeasures are available for humans.Here,based on self-assembled ferritin nanoparticles(FeNPs),we successfully constructed two candidate FeNP vaccines by loading mammalian cells expressing NiV sG(residues 71–602,FeNP-sG)and Ghead(residues 182–602,FeNP-Ghead)onto E.coli-expressed FeNPs(FeNP-sG and FeNP-Ghead,respectively)through Spycatcher/Spytag technology.Compared with sG and Ghead alone,FeNP-sG and FeNP-Ghead elicited significant NiV specific neutralizing antibody levels and T-cell responses in mice,whereas the immune response in the FeNP-sG immunized group was greater than that in the FeNP-Ghead group.These results further demonstrate that sG possesses greater antigenicity than Ghead and that FeNPs can dramatically enhance immunogenicity.Furthermore,FeNP-sG provided 100%protection against NiV challenge in a hamster model when it was administered twice at a dose of 5μg/per animal.Our study provides not only a promising candidate vaccine against NiV,but also a theoretical foundation for the design of a NiV immunogen for the development of novel strategies against NiV infection.
文摘The optimal use of intervention strategies to mitigate the spread of Nipah Virus (NiV) using optimal control technique is studied in this paper. First of all we formulate a dynamic model of NiV infections with variable size population and two control strategies where creating awareness and treatment are considered as controls. We intend to find the optimal combination of these two control strategies that will minimize the cost of the two control measures and as a result the number of infectious individuals will decrease. We establish the existence for the optimal controls and Pontryagin’s maximum principle is used to characterize the optimal controls. The numerical simulation suggests that optimal control technique is much more effective to minimize the infected individuals and the corresponding cost of the two controls. It is also monitored that in the case of high contact rate, controls have to work for longer period of time to get the desired result. Numerical simulation reveals that the spread of Nipah virus can be controlled effectively if we apply control strategy at early stage.
文摘Objective: To explore a common B-and T-cell epitope-based vaccine that can elicit an immune response against encephalitis causing genus Henipaviruses, Hendra virus(He V) and Nipah virus(Ni V). Methods: Membrane proteins F, G and M of He V and Ni V were retrieved from the protein database and subjected to different bioinformatics tools to predict antigenic B-cell epitopes. Best B-cell epitopes were then analyzed to predict their T-cell antigenic potentiality. Antigenic B-and T-cell epitopes that shared maximum identity with He V and Ni V were selected. Stability of the selected epitopes was predicted. Finally, the selected epitopes were subjected to molecular docking simulation with HLA-DR to confirm their antigenic potentiality in silico. Results: One epitope from G proteins, one from M proteins and none from F proteins were selected based on their antigenic potentiality. The epitope from the G proteins was stable whereas that from M was unstable. The M-epitope was made stable by adding flanking dipeptides. The 15-mer G-epitope(VDPLRVQWRNNSVIS) showed at least 66% identity with all Ni V and He V G protein sequences, while the 15-mer M-epitope(GKLEFRRNNAIAFKG) with the dipeptide flanking residues showed 73% identity with all Ni V and He V M protein sequences available in the database. Molecular docking simulation with most frequent MHC class-II(MHC II) and class-I(MHC I) molecules showed that these epitopes could bind within HLA binding grooves to elicit an immune response. Conclusions: Data in our present study revealed the notion that the epitopes from G and M proteins might be the target for peptide-based subunit vaccine design against He V and Ni V. However, the biochemical analysis is necessary to experimentally validate the interaction of epitopes individually with the MHC molecules through elucidation of immunity induction.
文摘Dear editor, In India, it is high time to focus on one health approach to address the emerging/reemerging disease. The fight between microbe and man influence the inexorable archenemy that needs to be dealt. Since Second World War, there has been an average increase in emergence or reemergence of new diseases particularly from an animal source (75%)(1)India is identified as a major hotspot area for infectious diseases in South Asia regarding zoonoses(2)As this emergence of India as a Zoonotic hotspot, the consequence of it to further on other region and global health raises queries to global preparedness concerning epidemic potential.
文摘Objective:To establish Nipah virus diagnostic capabilities at the National Reference Laboratory in Sri Lanka using the NIV Pune real-time PCR kit.Methods:Strict safety precautions were adhered during testing due to the high pathogenicity of the Nipah virus,with all diagnostics conducted in a BSL2+laboratory at the Medical Research Institute in Sri Lanka.RNA extraction was performed using the QIAamp Viral RNA Mini kit.The NIV Pune in-house real-time PCR kit was employed,following established primer/probe sequences and controls.The assay was validated using the Rotor-Gene Q Series Real-time PCR platform.Results:The validation run of the Nipah virus real-time PCR test demonstrated robust performance,with positive controls consistently detecting Nipah RNA at a Ct value of 21.50±0.01.Negative controls confirmed assay specificity with an external negative control which was also used as an extraction control and showed no interference.The internal control exhibited stable behavior,enhancing confidence in PCR results.The qPCR analysis graph illustrated the successful detection of internal and positive controls,validating the reliability of the assay.Conclusions:Establishing Nipah virus diagnostic capabilities in Sri Lanka signifies a proactive and collaborative response to the persistent global health threat.
