scholarly journals Effective inactivation of Nipah virus in serum samples for safe processing in low-containment laboratories

2020 ◽  
Author(s):  
Shumpei Watanabe ◽  
Shuetsu Fukushi ◽  
Toshihiko Harada ◽  
Masayuki Shimojima ◽  
Tomoki Yoshikawa ◽  
...  

Abstract Background: Nipah virus (NiV) is an emerging zoonotic paramyxovirus that causes severe encephalitis and respiratory disease with a high mortality rate in humans. During large outbreaks of the viral disease, serological testing of serum samples could be a useful diagnostic tool, which could provide information on not only the diagnosis of NiV disease but also the history of an individual with previous exposure to the virus, thereby supporting disease control. Therefore, an efficient method for the inactivation of NiV in serum samples is required for serological diagnosis. Methods: We determined the optimal conditions for the inactivation of NiV infectivity in human serum using heating and UV treatment. The inactivation method comprised UV irradiation with a cover of aluminum foil for 30 min and heating at 56°C for 30 min. Results: With an optimized protocol for virus inactivation, NiV infectivity in serum samples (containing 6.0 ×10 5 TCID 50 ) was completely inactivated. Conclusions: We developed a recommended protocol for the effective inactivation of NiV. This protocol would enable a regional or local laboratory to safely transport or process samples, including NiV, for serological testing in its biosafety level-2 facility.

2020 ◽  
Author(s):  
Shumpei Watanabe ◽  
Shuetsu Fukushi ◽  
Toshihiko Harada ◽  
Masayuki Shimojima ◽  
Tomoki Yoshikawa ◽  
...  

Abstract Background Nipah virus (NiV) is an emerging zoonotic paramyxovirus that causes severe encephalitis and respiratory disease with a high mortality rate in humans. During large outbreaks of the viral disease, serological testing of serum samples could be a useful diagnostic tool, which could provide information on not only the diagnosis of NiV disease but also the history of an individual with previous exposure to the virus, thereby supporting disease control. Therefore, an efficient method for the inactivation of NiV in serum samples is required for serological diagnosis. Methods We determined the optimal conditions for the inactivation of NiV infectivity in human serum using heating and UV treatment. The inactivation method comprised UV irradiation with a cover of aluminum foil for 30 min and heating at 56 °C for 30 min. Results With an optimized protocol for virus inactivation, NiV infectivity in serum samples (containing 6.4 × 105 TCID50) was completely inactivated. Conclusions We developed a recommended protocol for the effective inactivation of NiV. This protocol would enable a regional or local laboratory to safely transport or process samples, including NiV, for serological testing in its biosafety level-2 facility.


2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Shumpei Watanabe ◽  
Shuetsu Fukushi ◽  
Toshihiko Harada ◽  
Masayuki Shimojima ◽  
Tomoki Yoshikawa ◽  
...  

Abstract Background Nipah virus (NiV) is an emerging zoonotic paramyxovirus that causes severe encephalitis and respiratory disease with a high mortality rate in humans. During large outbreaks of the viral disease, serological testing of serum samples could be a useful diagnostic tool, which could provide information on not only the diagnosis of NiV disease but also the history of an individual with previous exposure to the virus, thereby supporting disease control. Therefore, an efficient method for the inactivation of NiV in serum samples is required for serological diagnosis. Methods We determined the optimal conditions for the inactivation of NiV infectivity in human serum using heating and UV treatment. The inactivation method comprised UV irradiation with a cover of aluminum foil for 30 min and heating at 56 °C for 30 min. Results With an optimized protocol for virus inactivation, NiV infectivity in serum samples (containing 6.0 × 105 TCID50) was completely inactivated. Conclusions We developed a recommended protocol for the effective inactivation of NiV. This protocol would enable a regional or local laboratory to safely transport or process samples, including NiV, for serological testing in its biosafety level-2 facility.


2020 ◽  
Author(s):  
Jianhui Nie ◽  
Qianqian Li ◽  
Jiajing Wu ◽  
Chenyan Zhao ◽  
Huan Hao ◽  
...  

Abstract Jianhui Nie, Qianqian Li, and Jiajing Wu contributed equally to this work.Pseudotyped viruses are useful virological tools due to their safety and versatility. Based on a VSV pseudotyped virus production system, we developed a pseudotyped virus-based neutralization assay against SARS-CoV-2 in biosafety level 2 facilities. This protocol includes production, titration of the SARS-CoV-2 S pseudotyped virus and neutralization assay based on it. Various types of samples targeting virus attachment and entry could be evaluated for their potency, including serum samples derived from animals and humans, monoclonal antibodies, fusion inhibitors (peptides or small molecules). If the pseudotyped virus stock has been prepared in advance, it will take 2 days to get the potency data for the candidate samples. Experience of handling cells is needed before implementing this protocol.


2008 ◽  
Vol 16 (1) ◽  
pp. 134-135 ◽  
Author(s):  
Nicholas Komar ◽  
Stanley Langevin ◽  
Thomas P. Monath

ABSTRACT A chimeric yellow fever virus/West Nile virus (WNV) was compared to WNV alone as a biosafety level 2 reagent in the plaque reduction neutralization test for determining WNV infection histories. Concordance was 96.3% among 188 avian and equine serum samples. Neutralizing antibody titers were frequently more than twofold lower with the chimera.


2016 ◽  
Vol 31 (2) ◽  
pp. 55-59 ◽  
Author(s):  
MSI Siddiqui ◽  
A Ahasan ◽  
N Islam ◽  
P Kundu ◽  
MN Munshi ◽  
...  

Peste des petits ruminants (PPR) is a highly contagious acute viral disease of domestic and wild ruminants particularly goats and sheep, which causes severe economic losses. Since 1993 PPR has been endemic in goats in Bangladesh. The present study was a seroprevalence study of PPR antibodies in goats and cattle at St. Martin's Island in Bangladesh from July 2012 to June 2013. There was no previous history of Rinderpest or PPR outbreak, and no Rinderpest vaccination. Blood samples were collected from 192 goats and 132 cattle randomly. All animals were apparently healthy, and were not vaccinated against Rinderpest or PPR. Serum antibody titre (competition percentage; CP value) was determined by a commercially available c-ELISA kit. The overall seroprevalence of PPR in goats was 37.5%. No serum samples from cattle were positive. In view of the high risk of PPR, a control strategy is proposed.Bangl. vet. 2014. Vol. 31, No. 2, 55-59


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
A. B. Sudeep ◽  
Pragya D. Yadav ◽  
Mangesh D. Gokhale ◽  
R. Balasubramanian ◽  
Nivedita Gupta ◽  
...  

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.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Ernesta Cavalcanti ◽  
Maria Antonietta Isgrò ◽  
Domenica Rea ◽  
Lucia Di Capua ◽  
Giusy Trillò ◽  
...  

Abstract Background Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection and the resulting disease, coronavirus disease 2019 (COVID-19), have spread to millions of people globally, requiring the development of billions of different vaccine doses. The SARS-CoV-2 spike mRNA vaccine (named BNT162b2/Pfizer), authorized by the FDA, has shown high efficacy in preventing SARS-CoV-2 infection after administration of two doses in individuals 16 years of age and older. In the present study, we retrospectively evaluated the differences in the SARS-CoV-2 humoral immune response after vaccine administration in the two different cohorts of workers at the INT - IRCCS “Fondazione Pascale” Cancer Center (Naples, Italy): previously infected to SARS-CoV-2 subjects and not infected to SARS-CoV-2 subjects. Methods We determined specific anti-RBD (receptor-binding domain) titers against trimeric spike glycoprotein (S) of SARS-CoV-2 by Roche Elecsys Anti-SARS-CoV-2 S immunoassay in serum samples of 35 healthcare workers with a previous documented history of SARS-CoV-2 infection and 158 healthcare workers without, after 1 and 2 doses of vaccine, respectively. Moreover, geometric mean titers and relative fold changes (FC) were calculated. Results Both previously infected and not infected to SARS-CoV-2 subjects developed significant immune responses to SARS-CoV-2 after the administration of 1 and 2 doses of vaccine, respectively. Anti-S antibody responses to the first dose of vaccine were significantly higher in previously SARS-CoV-2-infected subjects in comparison to titers of not infected subjects after the first as well as the second dose of vaccine. Fold changes for subjects previously infected to SARS-CoV-2 was very modest, given the high basal antibody titer, as well as the upper limit of 2500.0 BAU/mL imposed by the Roche methods. Conversely, for naïve subjects, mean fold change following the first dose was low ($$ \overline{x} $$ x ¯ =1.6), reaching 3.8 FC in 72 subjects (45.6%) following the second dose. Conclusions The results showed that, as early as the first dose, SARS-CoV-2-infected individuals developed a remarkable and statistically significant immune response in comparison to those who did not contract the virus previously, suggesting the possibility of administering only one dose in previously SARS-CoV-2-infected subjects. FC for previously infected subjects should not be taken into account for the generally high pre-vaccination values. Conversely, FC for not infected subjects, after the second dose, were = 3.8 in > 45.0% of vaccinees, and ≤ 3.1 in 19.0%, the latter showing a potential susceptibility to further SARS-CoV-2 infection.


2021 ◽  
Vol 10 (8) ◽  
pp. 1771
Author(s):  
Violetta Opoka-Winiarska ◽  
Ewelina Grywalska ◽  
Izabela Korona-Glowniak ◽  
Katarzyna Matuska ◽  
Anna Malm ◽  
...  

There is limited data on the effect of the novel coronavirus disease (COVID-19) caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) on pediatric rheumatology. We examined the prevalence of antibodies against SARS-CoV-2 in children with juvenile idiopathic arthritis (JIA) and a negative history of COVID-19 and the correlation of the presence of these antibodies with disease activity measured by juvenile arthritis disease activity score (JADAS). In total, 62 patients diagnosed with JIA, under treatment with various antirheumatic drugs, and 32 healthy children (control group) were included. Serum samples were analyzed for inflammatory markers and antibodies and their state evaluated with the juvenile arthritis disease activity score (JADAS). JIA patients do not have a higher seroprevalence of anti-SARS-CoV-2 antibodies than healthy subjects. We found anti-SARS-CoV-2 antibodies in JIA patients who did not have a history of COVID-19. The study showed no unequivocal correlation between the presence of SARS-CoV-2 antibodies and JIA activity; therefore, this relationship requires further observation. We also identified a possible link between patients’ humoral immune response and disease-modifying antirheumatic treatment, which will be confirmed in follow-up studies.


Author(s):  
Raquel Aitken Soares Mueller ◽  
Ana Cristina Cisne Frota ◽  
Daniela Durão Menna Barreto ◽  
Daniela Pires Ferreira Vivacqua ◽  
Gabriela Bueno Loria ◽  
...  

Abstract Objectives Identify missed opportunities for the prevention and early diagnosis of congenital toxoplasmosis (CT) in infants followed up in a reference center for pediatric infectious diseases (PID) in Rio de Janeiro between January 2007 and December 2016. Methods Descriptive study including infants with CT, diagnosis established based on Brazil’s Ministry of Health’s criteria. All data regarding the infants and their mother’s prenatal care were collected from the medical records of the Instituto de Puericultura e Pediatria Martagão Gesteira (IPPMG)—a tertiary public pediatric university hospital. The study enrolled infants aged between 0 and 12 months followed up in the PID department of IPPMG and with confirmed infection by Toxoplasma gondii in the period between January 2007 and December 2016. All patients with diagnosis of CT registered in the PID database of the IPPMG and admitted in the above-mentioned period were included in the study. Patients whose records were not available, or who went to just one clinic appointment were excluded. Results The obstetric history of all 44 women, whose infants (45) were diagnosed with CT, was analyzed. Their median age was 22 years. None had undergone preconception serological testing for toxoplasmosis. Only 20 (45%) of them started antenatal care during the first trimester of gestation, a total of 24 (55%) had more than six antenatal care visits, and 16% of those did not undergo serological testing for toxoplasmosis. None were adequately informed of preventive measures. The diagnosis of acute toxoplasmosis was made in 50% of these pregnancies but 32% of the women were not treated. Only 10 children of these mothers were adequately screened and treated at birth. Conclusion Despite the existence of national recommendations, several opportunities were missed to prevent CT during the antenatal period and to diagnose and treat this condition in the neonatal period.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Adrian Creanga ◽  
Rebecca A. Gillespie ◽  
Brian E. Fisher ◽  
Sarah F. Andrews ◽  
Julia Lederhofer ◽  
...  

AbstractBroadly neutralizing antibodies (bnAbs) have been developed as potential countermeasures for seasonal and pandemic influenza. Deep characterization of these bnAbs and polyclonal sera provides pivotal understanding for influenza immunity and informs effective vaccine design. However, conventional virus neutralization assays require high-containment laboratories and are difficult to standardize and roboticize. Here, we build a panel of engineered influenza viruses carrying a reporter gene to replace an essential viral gene, and develop an assay using the panel for in-depth profiling of neutralizing antibodies. Replication of these viruses is restricted to cells expressing the missing viral gene, allowing it to be manipulated in a biosafety level 2 environment. We generate the neutralization profile of 24 bnAbs using a 55-virus panel encompassing the near-complete diversity of human H1N1 and H3N2, as well as pandemic subtype viruses. Our system offers in-depth profiling of influenza immunity, including the antibodies against the hemagglutinin stem, a major target of universal influenza vaccines.


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