scholarly journals Nipah virus outbreak in Kerala state, India amidst of COVID-19 pandemic

2021 ◽  
Author(s):  
Pragya D. Yadav ◽  
Rima R. Sahay ◽  
B Anukumar ◽  
Sreelekshmy Mohandas ◽  
Chandni Radhakrishnan ◽  
...  
Keyword(s):  
Real Time ◽  
Neutralizing Antibodies ◽  
Index Case ◽  
Nipah Virus ◽  
Clinical Specimen ◽  
Antibody Detection ◽  
Adolescent Male ◽  
Rt Pcr ◽  
Awareness Campaigns ◽  
Kerala State

AbstractBackgroundWe report here a Nipah virus (NiV) outbreak in Kozhikode district of Kerala state, India which had caused fatal encephalitis in an adolescent male and the outbreak response which led to the successful containment of the disease and the related investigations.MethodsQuantitative real-time RT-PCR, ELISA based antibody detection and whole genome sequencing were performed to confirm the Nipah virus infection. Contacts of the index case were traced and isolated based on risk categorization. Bats from the areas near the epicenter of the outbreak were sampled for throat swabs, rectal swabs and blood samples for Nipah virus screening by real time RT-PCR and anti-Nipah virus bat IgG ELISA. Plaque reduction neutralization test was performed for the detection of neutralizing antibodies.ResultsNipah viral RNA and anti-NiV IgG antibodies were detected in the serum of the index case. Rapid establishment of an onsite NiV diagnostic facility and contact tracing helped in quick containment of the outbreak. NiV sequences retrieved from the clinical specimen of the index case formed a sub-cluster with the earlier reported Nipah I genotype sequences from India with more than 95% similarity. Anti-NiV IgG positivity could be detected in 21% of Pteropus medius and 37.73% of Rousettus leschenaultia. Neutralizing antibodies against NiV could be detected in P.medius.ConclusionsStringent surveillance and awareness campaigns needs to be implemented in the area to reduce human-bat interactions and minimize spill over events which can lead to sporadic outbreaks of NiV.

scholarly journals Detection of Nipah virus in Pteropus medius in 2019 outbreak from Ernakulam district, Kerala, India

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
A. B. Sudeep ◽  
Pragya D. Yadav ◽  
Mangesh D. Gokhale ◽  
R. Balasubramanian ◽  
Nivedita Gupta ◽  
...  
Keyword(s):  
Index Case ◽  
Nipah Virus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Genotype I ◽  
Visceral Organs ◽  
Distinct Cluster ◽  
New Genotype ◽  
Kerala State ◽  
Set Up

Abstract 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.

A clinical specimen collection and transport medium for molecular diagnostic and genomic applications

2010 ◽  
Vol 139 (11) ◽  
pp. 1764-1773 ◽  
Author(s):  
L. T. DAUM ◽  
S. A. WORTHY ◽  
K. C. YIM ◽  
M. NOGUERAS ◽  
R. F. SCHUMAN ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Real Time ◽  
Genetic Characterization ◽  
Clinical Specimen ◽  
Molecular Transport ◽  
Cold Chain ◽  
Molecular Diagnostic ◽  
Rt Pcr ◽  
Transport Medium ◽  
Specimen Collection

SUMMARYPathogen detection and genetic characterization has dramatically changed in recent years. Clinical laboratories are transitioning from traditional culture and primer-specific sequencing to more robust and rapid nucleic acid testing such as real-time PCR and meta-genomic characterization, respectively. Specimen collection is the first step in any downstream molecular diagnostic procedure. PrimeStore Molecular Transport Medium (MTM) is an optimized blend of nucleic acid stabilizing reagents that includes a non-specific internal positive control that can be amplified using real-time RT–PCR for tracking the integrity of a specimen from the point of collection to detection. PrimeStore MTM is shown here to effectively kill pathogens, including highly pathogenic H5 influenza virus, inactivate nucleases and to protect and preserve released RNA at ambient temperature for up to 30 days for downstream real-time and traditional RT–PCR detection and genetic characterization. PrimeStore MTM is also compatible with a variety of commercial extraction kits. PrimeStore is suited for routine clinical specimens and has added utility for field collection in remote areas, triage centres, border crossings and during pandemics where cold-chain, transport, and dissemination of potentially infectious pathogens are a concern.

scholarly journals Transmission and serotype features of hand foot mouth disease in household contacts in Dong Thap, Vietnam

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Cuong Quoc Hoang ◽  
Thao Thanh Thi Nguyen ◽  
Nguyen Xuan Ho ◽  
Hai Duc Nguyen ◽  
An Binh Nguyen ◽  
...  
Keyword(s):  
Attack Rate ◽  
Neutralizing Antibodies ◽  
Index Case ◽  
Fold Increase ◽  
Mouth Disease ◽  
Rt Pcr ◽  
Household Contacts ◽  
Two Samples ◽  
Household Members ◽  
Index Cases

Abstract Background Hand, foot and mouth disease (HFMD) has emerged as a major public health issue in Vietnam since 2003. We aimed to investigate the household transmission of HFMD and its causative viruses from 150 households in a high incidence province in Vietnam. Methods A longitudinal study was conducted in patients presenting to the provincial hospital with a HFMD-like syndrome, along with their household members between April and August 2014 in Dong Thap Province. Each participant was followed up for 2 weeks. We enrolled 150 patients aged under 15 who were clinically diagnosed with HFMD in Dong Thap Hospital, 600 household members, and 581/600 household members completed the study. All participants were interviewed using a standard questionnaire. Throat swabs and blood samples were taken for molecular detection of viruses and assessment of neutralizing antibodies, respectively. Index cases were defined using a clinical case definition, household contact cases were defined using a similar definition applied to the 2 weeks before admission and 2 weeks after discharge of the index case. Characteristics of index cases, household contacts, the attack rate, serotype features and related factors of HFMD were reported. Result Among 150 index cases, 113 were laboratory confirmed: 90/150 were RT-PCR-positive, 101/142 had a ≥ 4-fold increase of neutralizing antibody against Enterovirus A71 (EV-A71), Coxsackievirus (CV) A6 or CV-A16 across the two samples collected. 80/150 (53%) were males, and 45/150 (30%) were under the age of 1. The predominant serotype was CV-A6, identified in 57/87 (65.5%) of the specimens. No deaths were reported. Among 581 household contacts, 148 were laboratory confirmed: 12/581 were RT-PCR-positive, 142/545 had a ≥ 4-fold increase of neutralizing antibodies against EV-A71, CV-A6 or CV-A16; 4 cases experienced HFMD in the past 4 weeks. Attack rate among household contacts was 148/581 (25.5%). In 7/12 (58%) instances, the index and secondary cases were infected with the same serotype. Having a relationship to index case was significantly associated with EV infection. Conclusion The attack rate among household contacts was relatively high (25.5%) in this study and it seems justified to also consider the household setting as an additional target for intervention programs.

scholarly journals Development of a Fast SARS-CoV-2 IgG ELISA, Based on Receptor-Binding Domain, and Its Comparative Evaluation Using Temporally Segregated Samples From RT-PCR Positive Individuals

2021 ◽  
Vol 11 ◽  
Author(s):  
Farha Mehdi ◽  
Souvick Chattopadhyay ◽  
Ramachandran Thiruvengadam ◽  
Sarla Yadav ◽  
Manjit Kumar ◽  
...  
Keyword(s):  
Antibody Response ◽  
Receptor Binding ◽  
Neutralizing Antibodies ◽  
Elisa Test ◽  
Binding Domain ◽  
Antibody Detection ◽  
Receptor Binding Domain ◽  
Rt Pcr ◽  
Vaccine Response ◽  
Higher Sensitivity

SARS-CoV-2 antibody detection assays are crucial for gathering seroepidemiological information and monitoring the sustainability of antibody response against the virus. The SARS-CoV-2 Spike protein’s receptor-binding domain (RBD) is a very specific target for anti-SARS-CoV-2 antibodies detection. Moreover, many neutralizing antibodies are mapped to this domain, linking antibody response to RBD with neutralizing potential. Detection of IgG antibodies, rather than IgM or total antibodies, against RBD is likely to play a larger role in understanding antibody-mediated protection and vaccine response. Here we describe a rapid and stable RBD-based IgG ELISA test obtained through extensive optimization of the assay components and conditions. The test showed a specificity of 99.79% (95% CI: 98.82–99.99%) in a panel of pre-pandemic samples (n = 470) from different groups, i.e., pregnancy, fever, HCV, HBV, and autoantibodies positive. Test sensitivity was evaluated using sera from SARS-CoV-2 RT-PCR positive individuals (n = 312) and found to be 53.33% (95% CI: 37.87–68.34%), 80.47% (95% CI: 72.53–86.94%), and 88.24% (95% CI: 82.05–92.88%) in panel 1 (days 0–13), panel 2 (days 14–20) and panel 3 (days 21–27), respectively. Higher sensitivity was achieved in symptomatic individuals and reached 92.14% (95% CI: 86.38–96.01%) for panel 3. Our test, with a shorter runtime, showed higher sensitivity than parallelly tested commercial ELISAs for SARS-CoV-2-IgG, i.e., Euroimmun and Zydus, even when equivocal results in the commercial ELISAs were considered positive. None of the tests, which are using different antigens, could detect anti-SARS-CoV-2 IgGs in 10.5% RT-PCR positive individuals by the fourth week, suggesting the lack of IgG response.

scholarly journals Recombinant Nipah Virus Vaccines Protect Pigs against Challenge

2006 ◽  
Vol 80 (16) ◽  
pp. 7929-7938 ◽  
Author(s):  
Hana M. Weingartl ◽  
Yohannes Berhane ◽  
Jeff L. Caswell ◽  
Sheena Loosmore ◽  
Jean-Christophe Audonnet ◽  
...  
Keyword(s):  
Real Time ◽  
Nipah Virus ◽  
Neutralizing Antibody ◽  
Rt Pcr ◽  
Challenge Virus ◽  
Virus Shedding ◽  
Challenge Control ◽  
Human Infections ◽  
Antibody Levels

ABSTRACT Nipah virus (NiV), of the family Paramyxoviridae, was isolated in 1999 in Malaysia from a human fatality in an outbreak of severe human encephalitis, when human infections were linked to transmission of the virus from pigs. Consequently, a swine vaccine able to abolish virus shedding is of veterinary and human health interest. Canarypox virus-based vaccine vectors carrying the gene for NiV glycoprotein (ALVAC-G) or the fusion protein (ALVAC-F) were used to intramuscularly immunize four pigs per group, either with 108 PFU each or in combination. Pigs were boosted 14 days postvaccination and challenged with 2.5 × 105 PFU of NiV two weeks later. The combined ALVAC-F/G vaccine induced the highest levels of neutralization antibodies (2,560); despite the low neutralizing antibody levels in the F vaccinees (160), all vaccinated animals appeared to be protected against challenge. Virus was not isolated from the tissues of any of the vaccinated pigs postchallenge, and a real-time reverse transcription (RT)-PCR assay detected only small amounts of viral RNA in several samples. In challenge control pigs, virus was isolated from a number of tissues (104.4 PFU/g) or detected by real-time RT-PCR. Vaccination of the ALVAC-F/G vaccinees appeared to stimulate both type 1 and type 2 cytokine responses. Histopathological findings indicated that there was no enhancement of lesions in the vaccinees. No virus shedding was detected in vaccinated animals, in contrast to challenge control pigs, from which virus was isolated from the throat and nose (102.9 PFU/ml). Based on the data presented, the combined ALVAC-F/G vaccine appears to be a very promising vaccine candidate for swine.

Specific detection of Nipah virus using real-time RT-PCR (TaqMan)

2004 ◽  
Vol 120 (2) ◽  
pp. 229-237 ◽  
Author(s):  
Vanessa Guillaume ◽  
Annabelle Lefeuvre ◽  
Caroline Faure ◽  
Philippe Marianneau ◽  
Robin Buckland ◽  
...  
Keyword(s):  
Real Time ◽  
Nipah Virus ◽  
Rt Pcr ◽  
Specific Detection

scholarly journals Menangle virus, a pteropid bat paramyxovirus infectious for pigs and humans, exhibits tropism for secondary lymphoid organs and intestinal epithelium in weaned pigs

2012 ◽  
Vol 93 (5) ◽  
pp. 1007-1016 ◽  
Author(s):  
Timothy R. Bowden ◽  
John Bingham ◽  
Jennifer A. Harper ◽  
David B. Boyle
Keyword(s):  
Real Time ◽  
Intestinal Epithelium ◽  
Neutralizing Antibodies ◽  
Time Course ◽  
Lymphoid Organs ◽  
Lymphoid Tissues ◽  
Rt Pcr ◽  
Weaned Pigs ◽  
Reproductive Disease ◽  
Secondary Lymphoid Organs

This study is the first report of experimental infection and transmission of Menangle virus (MenPV) in pigs. Isolated in 1997 from piglets that were stillborn at a large commercial piggery in New South Wales, Australia, MenPV is a recently identified paramyxovirus of bat origin that causes severe reproductive disease in pigs and an influenza-like illness, with a rash, in humans. Although successfully eradicated from the infected piggery, the virus was only isolated from affected fetuses and stillborn piglets during the period of reproductive disease, and thus the mode of transmission between pigs was not established. To investigate the pathogenesis of MenPV, we undertook time-course studies in 6-week-old pigs following intranasal administration of a low-passage, non-plaque-purified isolate from the lung of an infected stillborn piglet. Viraemia was of short duration and low titre, as determined by real-time RT-PCR and virus isolation. Following an incubation period of 2–3 days, virus was shed in nasal and oral secretions, faeces and urine, typically for less than 1 week. Cessation of shedding correlated with the development of neutralizing antibodies in sera. Secondary lymphoid organs and intestine were identified, using quantitative real-time RT-PCR, as major sites of viral replication and dissemination, and this was confirmed by positive immunolabelling of viral antigen within various lymphoid tissues and intestinal epithelium. These data provide new insights into the pathogenesis of MenPV in weaned pigs, and will facilitate future control and eradication programmes should it ever re-emerge in the pig population.

scholarly journals The comparative superiority of IgM-IgG antibody test to real-time reverse transcriptase PCR detection for SARS-CoV-2 infection diagnosis

2020 ◽  
Author(s):  
Rui Liu ◽  
Xinghui Liu ◽  
Huan Han ◽  
Muhammad Adnan Shereen ◽  
Zhili Niu ◽  
...  
Keyword(s):  
Real Time ◽  
False Negative ◽  
Antibody Test ◽  
Pcr Detection ◽  
Antibody Detection ◽  
Rt Pcr ◽  
Igg Antibody ◽  
Positive Ratio ◽  
Infection Diagnosis ◽  
Significant Difference

AbstractBackgroundAs the increasing number of Corona Virus Disease 2019 (COVID-19) patients caused by the severe acute respiratory coronavirus 2 (SARS-CoV-2), which caused an outbreak initiated from Wuhan, China in December, 2019, the clinical features and treatment of COVID-19 patients have been understood. However, it is urgent to need the rapid and accurate detection for SARS-CoV-2 infection diagnosis. We aimed to evaluate the antibodies-based and nucleic acid-based tests (NAT) for SARS-CoV-2-infected patients.MethodWe retrospectively and observationally studied 133 patients diagnosed with SARS-CoV-2 and admitted in Renmin Hospital of Wuhan University, China, from Feb 17 to Mar 1, 2020. Demographic data, symptoms, clinical examination, laboratory tests, and clinical outcomes were collected. Data were compared between IgM-IgG antibody test and real-time RT-PCR detection for COVID-19 patients.ResultsOf 133 patients with SARS-CoV-2 infection, there were 44 moderate cases, 52 severe cases, and 37 critical cases with no significant difference of gender and age among three subgroups. Overall, the positive ratio in IgM antibody test was higher than in RT-PCR detection. In RT-PCR detection, the positive ratio was 65.91%, 71.15%, and 67.57% in moderate, severe, and critical cases, respectively. Whereas, the positive ratio of IgM/IgG antibody detection in patients was 79.55%/93.18%, 82.69%/100%, and 72.97%/97.30% in moderate, severe, and critical cases, respectively. Moreover, the concentrations of antibodies were also measured in three subgroups.ConclusionThe IgM-IgG antibodies-based test exhibited a comparative superiority to the NAT for COVID-19 diagnosis, which provides an effective complement to the false negative results from NAT for SARS-CoV-2 infection diagnosis.

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