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Please note: These are preprints and have not been peer reviewed. Data may be preliminary.
The N-terminal domain of Spike protein contributes to antigenicity difference between...
Qi-long Qiao
Ning Li

Qi-long Qiao

and 6 more

March 01, 2021
Porcine epidemic diarrhea virus (PEDV) strains have been clarified into two genotypes, G1 and G2, based on the sequence of the spike (S) gene. Amino acid mutations that distinguish the two PEDV genotypes were mostly located in the N-terminal domain (NTD) (aa 1-380) of S protein. The fact of increased outbreaks of G2 subtype PEDV and the failure of G1 subtype PEDV strain (CV777)-based vaccine in China since 2010 suggested that multiple amino acid mutations located in the NTD altered the antigenicity of S protein. To determine the role of the NTD of S protein in the antigenicity difference, the NTD of the CV777 vaccine strain (G1) and CH/ZMDZY/11 strain (G2) was expressed in E. coli, respectively. polyclonal antibodies (PAbs) against genotype-specific S proteins were prepared by immunizing BALB/c mice using purified S proteins. Antigenicity was systematically compared by detection of PAbs against two genotype PEDV strains and purified S proteins using Western blot, indirect enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence assay (IFA), and serum cross-neutralization assay (SN). Consistent with the multiple amino acid mutations in the NTD of S protein, different antigenic cross-reactivity between the two genotypes was demonstrated. There was six-fold and more than twenty-fold difference in ELISA and SN titer between anti-CV777 S protein antibodies against G1 and G2 subtype strains, respectively. There was twofold and eight-fold difference in ELISA and SN titer between anti-ZMDZY S protein antibodies against G1 and G2 genotype strains, respectively. The results proved that the NTD of S protein contributes to the antigenicity difference between PEDV genotypes G1 and G2, and highlighted a G2 strain should be used to develop a vaccine for providing better protection against prevalent genotype of PEDV.
Cutaneous and systemic hyperinflammation drives maculopapular drug exanthema in sever...
yasutaka mitamura
Daniel Schulz

yasutaka mitamura

and 18 more

February 23, 2021
Title:
Risk assessment of Avian Influenza and Newcastle disease viruses exposure from perido...
Julien Hirschinger
Timothée Vergne

Julien Hirschinger

and 5 more

February 22, 2021
Worldwide, wild birds are frequently suspected to be involved in the occurrence of outbreaks in captive-bred birds although proofs are lacking and most of the dedicated studies are insufficiently conclusive to confirm or characterize the roles of wild birds in such outbreaks. The aim of this study was to assess and compare, for the most prevalent peridomestic wild birds, the different exposure routes for Avian Influenza and Newcastle disease viruses in conservation breeding sites of Houbara bustards in the United Arab Emirates. To do so, we considered all of the potential pathways by which captive bustards could be exposed to Avian Influenza and Newcastle disease viruses by wild birds, and ran a comparative study of the likelihood of exposure via each of the pathways considered. We merged data from an ecological study dedicated to local wild bird communities with an analysis of the contacts between wild birds and captive bustards and with a prevalence survey of AIV and NDV in wild bird populations. We also extracted data from an extensive review of the scientific literature and by the elicitation of expert opinion. Overall, this analysis highlighted that captive bustards had a high risk of being exposed to pathogens by wild birds. This risk was higher for Newcastle disease virus than Avian influenza virus, and House sparrows represented the riskiest species for the transmission of both viruses through indirect exposure from consumption of water contaminated from the faeces of an infectious bird that got inside the aviary. Thus, this analysis reveals that wild peridomestic birds may play a role in the transmission of avian pathogens to captive bred birds. These results also reaffirm the need to implement sanitary measures to limit contacts between wild and captive birds and highlight priority targets for a thoughtful and efficient sanitary management strategy.
Silencing of SARS-CoV-2 with modified siRNA-peptide dendrimer formulation
Musa Khaitov
Alexandra Nikonova

Musa Khaitov

and 27 more

February 17, 2021
Background. First vaccines for prevention of Coronavirus disease 2019 (COVID-19) are becoming available but there is a huge and unmet need for specific forms of treatment. In this study we aimed to evaluate the potent anti-SARS-CoV-2 effect of siRNA both in vitro and in vivo. Methods. To identify most effective molecule out of a panel of 15 in silico designed siRNAs, an in vitro screening system based on vectors expressing SARS-CoV-2 genes fused with the firefly luciferase reporter gene and SARS-CoV-2-infected cells was used. The most potent siRNA, siR-7, was modified by Locked nucleic acids (LNAs) to obtain siR-7-EM with increased stability and was formulated with the peptide dendrimer KK-46 for enhancing cellular uptake to allow topical application by inhalation of the final formulation - siR-7-EM/KK-46. Using the Syrian Hamster model for SARS-CoV-2 infection the antiviral capacity of siR-7-EM/KK-46 complex was evaluated. Results. We identified the siRNA, siR-7, targeting SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) as the most efficient siRNA inhibiting viral replication in vitro. Moreover, we have shown that LNA-modification and complexation with the designed peptide dendrimer enhanced the antiviral capacity of siR-7 in vitro. We demonstrated significant reduction of virus titer and total lung inflammation in the animals exposed by inhalation of siR-7-EM/KK-46 in vivo. Conclusions. Thus, we developed a therapeutic strategy for COVID-19 based on inhalation of a modified siRNA-peptide dendrimer formulation.
Novel mutations in the spike protein of SARS CoV 2 from Bangladesh
Sultana   Afrin
Jahan  Begum

Sultana Afrin

and 7 more

February 17, 2021
Genetic characterization may provide useful insights into severe acute respiratory coronavirus 2 (SARS CoV 2) circulating in Bangladesh. Here we analyzed the SARS Cov 2 positive 41 nasopharyngeal samples collected in lysis buffer obtained at different regional national laboratories of Bangladesh during July – December 2020. Full length spike gene was amplified and SARS CoV 2 was confirmed upon Sanger sequencing. Multiple ClustalW alignment and phylogenetic study of 15 strains showed that genetically diverse SARS CoV 2 is circulating in the country where 80 documented and 55 novel substitutions have been observed in different regions of spike glycoprotein. Major mutations and/or deletions was identified at conserved amino acid positions that are functionally linked to host transition, antigenic drift, host surface receptor binding or antibody recognition sites, and viral oligomerization interfaces that may have significant effects on pathogenic capacity and epidemiological signatures.
THE VIROME OF RHIPICEPHALUS, DERMACENTOR AND HAEMAPHYSALIS TICKS FROM EASTERN ROMANIA...
Bianca Brătuleanu
Sarah Temmam

Bianca Brătuleanu

and 8 more

February 16, 2021
Ticks are involved in the transmission of various pathogens and some tick-borne diseases cause significant problems for the health of humans and livestock. Despite their obvious importance, the composition of viral communities in ticks, and their interactions with pathogens, is poorly understood, particularly in Eastern Europe that constitutes (via bird migrations for example) a major hub for animal-arthropod vectors exchanges. The aim of this study was first to describe the virome of Dermacentor sp., Rhipicephalus sp. and Haemaphysalis sp. ticks collected from poorly investigated regions of Romania (Iasi and Tulcea counties) located at the intersection of various biotopes, countries and routes of migrations. We then focused the study on viruses that could have potential relevance for human and animal health. More than 500 ticks were collected in 2019 from the environment and from small ruminants and analyzed by high-throughput transcriptome sequencing. Among the viral communities infecting Romanian ticks, viruses belonging to the Flaviviridae, Phenuiviridae and Nairoviridae families were identified and full genomes were derivedPhylogenetic analyses placed them in clades where mammalian isolates are found, suggesting that these viruses could constitute novel arboviruses. We also assessed the bacterial microbiome of the collected ticks. The characterization of these microbial communities increases the knowledge of the diversity of viruses in Eastern Europe and provide a basis for further studies on the relationship between ticks and tick-borne viruses.
Detection and genetic characterization of porcine sapovirus from pigs with diarrhea
Huigang Shen
Jianfeng Zhang

Huigang Shen

and 9 more

February 13, 2021
Porcine Sapovirus (SaV) was first identified by electron microscopy in the United States in 1980 and has since been reported from both asymptomatic and diarrheic pigs usually in mixed infection with other enteric pathogens. SaV as the sole etiological agent of diarrhea in naturally infected pigs has not previously been reported in the United States. Here, we used four independent lines of evidence including metagenomics analysis, real-time RT-PCR (rRT-PCR), histopathology, and in situ hybridization to confirm porcine SaV genogroup III (GIII) as the sole cause of enteritis and diarrhea in pigs. A highly sensitive and specific rRT-PCR was established to detect porcine SaV GIII. Examination of 184 fecal samples from the outbreak farm showed that pigs with clinical diarrhea had significantly lower Ct values (15.9 ± 0.59) compared to clinically unaffected pigs (35.8 ± 0.71). Further survey of 336 fecal samples from different states in the United States demonstrated that samples from pigs with clinical diarrhea had a comparable positive rate (45.3%) with those from non-clinical pigs (43.1%). However, the SaV-positive pigs with clinical diarrhea had significantly higher viral loads (Ct = 26.0 ± 0.5) than those positive but clinically healthy pigs (Ct = 33.2 ± 0.9). Phylogenetic analysis of 20 field SaVs revealed that all belonged to SaV GIII and recombination analysis indicated that intra-genogroup recombination occurred within the field isolates of SaV GIII. These results suggest that porcine SaV GIII plays an important etiologic role in swine enteritis and diarrhea and rRT-PCR is a reliable method to detect porcine SaV. Our findings provide significant insights to better understand the epidemiology and pathogenicity of porcine SaV.
The Impact of COVID-19 on Pregnancy and Emerging Therapeutic Drug Development Options
Allyah Abbas-Hanif
Homira Rezai

Allyah Abbas-Hanif

and 2 more

February 12, 2021
Emerging data shows pregnant women with COVID-19 are at significantly higher risk of severe outcomes compared to non-pregnant women of similar age. This review discusses the invaluable insight revealed from vaccine clinical trials in women who were vaccinated and inadvertently became pregnant during the trial period. It further explores a number of clinical avenues in their management and proposes a drug development strategy in-line with clinical trials for vaccines and drug treatments for the drug development community. Little is known of the long-term effects of COVID-19 on the mother and the baby. We provide a rationale for our hypothesis that COVID-19 predisposes pregnant women to cardiovascular diseases later in life, in a similar way, to preeclampsia and may increase the risk of preeclampsia in their subsequent pregnancy. This is an ever-evolving landscape and early knowledge for healthcare providers and drug innovators is offered to ensure benefits outweigh the risks.
LAMP assay coupled with CRISPR/Cas12a system for portable detection of African swine...
Bo YANG
zhengwang shi

Bo YANG

and 11 more

February 10, 2021
African swine fever (ASF) is one of the most severe infectious diseases of pigs. In this study, a LAMP assay coupled with the CRISPR Cas12a system was established in one tube for the detection of the ASFV p72 gene. The single-strand DNA-fluorophore-quencher (ssDNA-FQ) reporters and CRISPR-derived RNA (crRNAs) were screened and selected for the CRISPR detection system. In combination with LAMP amplification assay, the detection limit for the LAMP-CRISPR assay can reach 7 copies/μl of p72 gene per reaction. Furthermore, this method displays no cross-reactivity with other porcine DNA or RNA viruses. The performance of the LAMP-CRISPR assay was compared with real-time qPCR tests for clinical samples, a good consistency between the LAMP-CRISPR assay and real-time qPCR was observed. In the current study, a LAMP coupled with the CRISPR detection method was developed. The method shed a light on the convenient, portable, low cost, highly sensitive and specific detection of ASFV, demonstrating a great application potential for monitoring on-site ASFV in the field.
Improved multiplex PCR method for the detection of diverse Megalocytivirus in the Kor...
Han Chang Sohn
Seongdo Lee

Han Chang Sohn

and 5 more

February 05, 2021
Megalocytivirus is a genus of piscine viruses that belongs to the Iridoviridae family, and this family comprises red seabream iridovirus (RSIV), turbot reddish body iridovirus (TRBIV), and infectious spleen and kidney necrosis virus. RSIV causes high mortality and economic losses in the rock bream (Oplegnathus fasciatus) Korean aquaculture industry. The World Organization for Animal Health’s Office International des Epizooties has provided a manual for RSIV detection. However, detection against TRBIV has not been confirmed. In this study, a multiplex PCR method was established to detect two genotypes of Megalocytivirus, RSIV and TRBIV. New primer pairs were optimized for the PCR reaction. A mixture of one universal and two specific primer pairs could amplify three distinct products targeting three different genes. The sensitivity of the primer pairs was evaluated and results showed a detection limit of 2.0  105 copies for each target gene. Moreover, the primer pairs did not amplify any other viruses. The evaluation of multiplex PCR using 21 RSIV Korean isolates has shown that it can distinguish two genotypes of Megalocytivirus from 21 RSIV Korean isolates. Finally, we describe a new multiplex PCR method to detect different genotypes of Megalocytivirus simultaneously, which makes the diagnosis of viral diseases occurring in the Korean aquaculture industry more convenient.
Evidence of viral survival in representative volumes of feed and feed ingredients dur...
Scott Dee
Apoorva Shah

Scott Dee

and 8 more

February 03, 2021
The hypothesis that feed ingredients could serve as vehicles for the transport and transmission of viral pathogens was first validated under laboratory conditions. To bridge the gap from the laboratory to the field, this current project tested whether three significant viruses of swine could survive in feed ingredients during long-distance commercial transport across the continental US. One-metric ton totes of soybean meal (organic and conventional) and complete feed were spiked with a 10 mL mixture of PRRSV 174, PEDV, and SVA and transported for 23 days in a commercial semi-trailer truck, crossing 29 states, and 10,183 km. Samples were tested for the presence of viral RNA by PCR, and for viable virus in soy-based samples by swine bioassay and in complete feed samples by natural feeding. Viable PRRSV, PEDV, and SVA were detected in both soy products and viable PEDV and SVA in complete feed. These results provide the first evidence that viral pathogens of pigs can survive in representative volumes of feed and feed ingredients during long-distance commercial transport across the continental US.
Patterns of rabies cases in South Africa between 1993-2019, including the role of wil...
Katja Koeppel
Ockert van Schalkwyk

Katja Koeppel

and 2 more

February 02, 2021
Rabies is a global viral zoonosis endemic to South Africa, resulting in fatal encephalitis in warm blooded animals, including humans. The loss of human lives and economic losses in rural areas through loss of livestock are substantial. A review was conducted of all confirmed rabies cases in South Africa from 1993 to 2019, with a total of 11 701 cases identified to species level to assess the wildlife plays in the epidemiology of rabies. A spatiotemporal cluster analysis using a discrete Poisson space-time probability model, accounting for underlying estimated dog and livestock densities, identified 13 significant clusters (p<0.05). These included four long-term clusters lasting more than 8 years in duration and seven short term clusters lasting less than 2 years, with the remaining two clusters being of intermediate length. Outside of these endemic clusters, wildlife outbreaks in the remainder of South Africa were often less than one and a half years in duration most likely due to the rapid decline of wildlife vectors, especially jackals associated with rabies infection. Domestic dogs accounted for 59.8% of cases, with domestic cats (3.2%), livestock (21.1%) and wildlife (15.8%) making up the remainder of the cases. Yellow mongoose (Cynictis penicillate) was the most frequently affected wildlife species, followed by bat-eared fox (Otocyon megalotis), black-backed jackal (Canis mesomelas), meerkat (Suricata suricatta) and aardwolf (Proteles cristatus). Rabies in wildlife species followed different spatial distributions: black-backed jackal cases were more common in the north-western parts of South Africa, yellow mongoose cases more frequent in central South Africa, and bat-eared fox and aardwolf cases were more frequent in southern and western South Africa. Clusters often spanned several provinces, showing the importance of coordinated rabies control campaigns across administrative boundaries, and high-risk areas were highlighted for rabies in South Africa.
The impact of African Swine Fever Virus on smallholder village pig production: an out...
Nina Matsumoto
J Siengsanan-Lamont

Nina Matsumoto

and 10 more

February 02, 2021
African Swine Fever Virus (ASFV) causes a deadly disease of pigs which spread through southeast Asia in 2019. We investigated one of the first outbreaks of ASFV in Lao Peoples Democratic Republic amongst smallholder villages of Thapangtong District, Savannakhet Province. In this study, two ASFV affected villages were compared to two unaffected villages. Evidence of ASFV-like clinical signs appeared in pig herds as early as May 2019, with median epidemic days on 1 and 18 June in the two villages, respectively. Using participatory epidemiology mapping techniques, we found statistically significant spatial clustering in both outbreaks (P < 0.001). Villagers reported known risk factors for ASFV transmission  such as free-ranging management systems and wild boar access  in all four villages. The villagers reported increased pig trader activity from Vietnam before the outbreaks; however, the survey did not determine a single outbreak source. The outbreak caused substantial household financial losses with an average of 9 pigs lost to the disease, and Monte Carlo analysis estimated this to be USD 215 per household. ASFV poses a significant threat to food and financial security in smallholder communities such as Thapangtong, where 40.6% of the district’s population are affected by poverty. This study shows ASFV management in the region will require increased local government resources, knowledge of informal trader activity and wild boar monitoring alongside education and support to address intra-village risk factors such as free-ranging, correct waste disposal and swill feeding.
Epidemiological and phylogenetic analyses of COVID-19 in Africa using open-source seq...
Chigozie NWACHUKWU
C Raina MacIntyre

Chigozie NWACHUKWU

and 2 more

January 25, 2021
Between late December 2019 to early September 2020, over 10 million people globally were reportedly infected by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), responsible for the coronavirus disease-2019 (COVID-19). In Africa, more than 300,000 infection occurred within the period, from which several viral genetic sequences were generated. Phylogenetic reconstruction of genomic data can provide epidemiological inferences about time of pathogen introduction, epidemic growth rate and temporal-spatial spread of the infection during disease outbreak. In this work, we studied the genetic epidemiology of COVID-19 in Africa. Genetic sequence data of SARS-CoV-2 and metadata from African countries were obtained from open-source sequence database hosted by the GISAID initiative. Whole genome sequences were subjected to multiple sequence alignment, from which Maximum Likelihood phylogenetic tree was constructed based on the general time reversible model. Of the 227 genetic sequences obtained for 9 African countries (DRC=133, Senegal=23, South Africa=20, Ghana=15, Tunisia=6, Algeria=3, Gambia=3, Egypt=2 and Nigeria=2), 220 were whole genome sequences while 7 were partial genome sequences of the surface glycoprotein S. Phylogenetic analysis confirmed multiple introductions of the virus to the continent from multiple external sources prior to local adaptation and spread. The very close alignment of three viruses - Ghana/1659_S14/2020|EPI_ISL_422405, DRC/KN0054/2020|EPI_ISL_417437, and South_Africa/R05475/2020|EPI_ISL_435059 – to the reference Wuhan strain on the time tree, suggests possible introduction and circulation of the virus into the continent much earlier than when the first case was announced on February 15 2020. In conclusion, this study provided evidence to support multiple introductions of SARS-CoV-2 into Africa, and further suggests that the virus may have already been circulating in the continent prior to official reporting of the first case. Also, there is strong impression to infer likely genetic adaptation of the virus in the continent that may account for the close clustering of isolates from different countries.
Development of a competitive chemiluminescence immunoassay using a monoclonal antibod...
Wei Liu
Guanglei Zhang

Wei Liu

and 7 more

January 24, 2021
Foot-and-mouth disease (FMD) is a devastating animal disease. Differentiation of infected from vaccinated animals (DIVA) is very important for confirming suspected cases, evaluating the prevalence of infection, certifying animals for trade and controlling the disease. In this study, a competitive chemiluminescence immunoassay (3B-cCLIA) for DIVA was developed for the rapid detection of antibodies against non-structural proteins (NSPs) in different species of livestock animals using monoclonal antibody 9E2 as a competitive antibody that recognizes NSP 3B, which only needs to be washed once and takes 15 min. The cut-off (50%), diagnosis sensitivity (97.20%, 95.71%, and 96.15%) and diagnosis specificity (99.51%, 99.43%, and 98.36) of the assay were estimated by testing a panel of known background sera from swine, cattle and sheep. The accuracy rate of 3B-cCLIA was also validated and compared with that of two commercial diagnostic kits. The early diagnostic performance showed that antibodies to NSPs occurred later (approximately 1–2 days) than antibodies to structural proteins. Furthermore, NSP antibodies present in animals vaccinated multiple times (false-positive), especially in cattle and sheep, were confirmed, and the false-positive rate increased with the number of vaccinations. These results indicated that 3B-cCLIA is suitable to rapidly detect antibodies against FMDV NSP 3B in a wide range of species for DIVA.
Detection and genetic analysis of a novel atypical porcine pestivirus from piglets wi...
Miwako Kasahara-Kamiie
Mitsuo Kagawa

Miwako Kasahara-Kamiie

and 9 more

January 24, 2021
Atypical porcine pestivirus (APPV), which has been confirmed to be associated with congenital tremor (CT) in pigs, is a newly discovered porcine virus that has been found in the Americas, Europe, and Asia; however, no report of APPV in Japan has been published. We identified an APPV in the central nervous system of Japanese piglets with CT, and firstly determined and analyzed the complete genome sequence. Phylogenetic analysis using the complete genome nucleotide sequence of the Japanese APPV, named Anna/2020, and those of APPVs from the NCBI database showed that APPVs were divided into three genotypes (genotypes 1 to 3), and that Anna/2020 clustered with the genotype 3 APPV strains, but distantly branched from these strains. Pairwise complete coding region nucleotide sequence comparisons revealed that there was 94.0% to 99.7% sequence identity among the genotype 3 strains, while Anna/2020 showed 87.0% to 89.3% identity to those genotype 3 strains, suggesting that Anna/2020 represents a novel APPV lineage within genotype 3. Retrospective examinations using RT-PCR revealed one genotype 1 and two novel genotype 3 APPVs from pigs without CT, and that novel genotype 3 APPVs have been prevalent in Japan since at least 2007.
Therapeutic strategies to fight COVID-19: which is the status artis?
Cristina Scavone
Annamaria Mascolo

Cristina Scavone

and 12 more

January 18, 2021
COVID-19 is a complex disease and many difficulties are faced today especially in the proper choice of pharmacological treatments. The role of antiviral agents for COVID-19 is still being investigated. The evidence for immunomodulatory and anti-inflammatory drugs is quite conflicting, while the use of corticosteroids is supported by robust evidence. The use of heparins in hospitalized critically ill patients is preferred over other anticoagulants. Lastly, conflicting data were found regarding to the use of convalescent plasma and vitamin D. According to data shared by the WHO, many vaccines are under phase 3 clinical trials and some of them already received the marketing approval in EU countries and in the US. In conclusion, drugs repurposing has represented the main approach recently used in the treatment of patients with COVID-19. At this moment, the analysis of efficacy and safety data of drugs and vaccines used in real life context is strongly needed.
Stability of African swine fever virus on contaminated spray dried porcine plasma
Melina Fischer
Jutta Pikalo

Melina Fischer

and 3 more

January 17, 2021
African swine fever (ASF) is a viral disease that affects members of the Suidae family. The notifiable disease is considered a major threat to the pig industry, animal health, and food security worldwide. According to the European Food Safety Authority, ASF virus (ASFV) survival and transmission in feed and feed materials is a major research gap. Against this background, the objective of this study was to determine the survival of ASFV on re-contaminated spray dried porcine plasma (SDPP) when stored at two different temperatures. To this means, commercial SDPP granules were contaminated with high titers of ASFV in a worst-case re-contamination scenario. Three samples per time point and temperature condition were subjected to blind passaging on macrophage cultures and subsequent haemadsorption test to determine residual infectivity. In addition, viral genome was detected by real-time PCR. The results indicate that heavily re-contaminated SDPP stored at 4°C remains infectious for at least five weeks. In contrast, contaminated SDPP stored at room temperature displayed a distinct ASFV titer reduction after one week and complete inactivation after two weeks. In conclusion, the residual risk of ASFV transmission through re-contaminated SDPP is low, if SDPP is stored at room temperature for a period of at least two weeks before feeding.
Traceable Surveillance and Genetic Diversity Analysis of Coronaviruses in Poultry fro...
Yang Li
Qingye Zhuang

Yang Li

and 18 more

January 06, 2021
Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first reported in Wuhan, China, and rapidly spread worldwide. This new emerging pathogen is highly transmittable and can cause fatal disease. More than 35 million cases have been confirmed and the fatality was about 2.9% up to October 9 2020. However, the original and intermediate hosts of SARS-CoV-2 remain unknown. Here, a total of 3160 poultry samples collected from 14 provinces between September and December 2019 in China were tested for the purpose of traceable surveillance for SARS-CoV-2 infection. The results indicated that all samples were SARS-CoV-2 negative, and a total of 593 avian coronaviruses were detected, including 485 avian infectious bronchitis viruses, 72 duck coronaviruses and 36 pigeon coronaviruses. The positive rates of avian infectious bronchitis virus, duck coronavirus, and pigeon coronavirus were 15.35%, 2.28% and 1.14%, respectively. Our surveillance demonstrated the diversities of avian coronaviruses in China, and higher prevalence were also recognized in some regions. The possibility of SARS-CoV-2 originating from the known avian-origin coronaviruses can be preliminarily ruled out. More surveillance and research on avian coronaviruses should be strengthened for better understanding the diversity, distribution, cross-species transmission and clinical significance of these viruses.
The immune response does not prevent homologous Porcine epidemic diarrhoea virus rein...
Ivan Díaz
Joan Pujols

Ivan Díaz

and 7 more

January 05, 2021
The aim of the present study was to evaluate the duration of protective immunity against Porcine epidemic diarrheoa virus (PEDV). To that, a two phases study was performed. In the first phase, 75 four-week-old pigs (group A) were orally inoculated (0 days post-inoculation; dpi) with a European PEDV G1b strain and 14 were kept as controls (group B). The second phase started five month later (154 dpi), when animals in group A were homologous challenged and animals in group B were challenged for first time. Clinical signs, viral shedding and immune responses were evaluated after each inoculation, including the determination of antibodies (ELISA and viral neutralisation test, IgA and IgG ELISPOTs using peripheral blood mononuclear cells and lymph node cells) and the frequency of interferon-gamma (IFN-γ) secreting cells. During the first phase, loose stools/liquid faeces were observed in all group A animals. Faecal shedding of PEDV occurred mostly during the first 14 days but, in some animals, persisted until 42 dpi. All inoculated animals seroconverted for specific-PEDV IgG and IgA, and for neutralizing antibodies (NA). At 154 dpi, 77% of pigs were still positive for NA. After that, the homologous challenge resulted in a booster for IgG, IgA, NA, as well as specific-PEDV IgG, IgA and IFN-γ secreting cells. In spite of that, PEDV was detected in faeces of all pigs from group A, indicating that the immune response did not prevent reinfection although the duration of the viral shedding and the total load of virus shed was significantly lower for previously challenged pigs (p<0.05). Taken together, the results indicated that, potentially, maintenance of PEDV infection within an endemic farm may occur by transmission to and from previously infected animals and also indicates that sterilising immunity is shorter than the productive life of pigs.
ACE2 receptor, TRL-4 and SARS CoV-2: Do long acting opioids and opioid antagonists ha...
Marie Eagleton
Siobhan Stokes

Marie Eagleton

and 3 more

December 28, 2020
Despite the advent of a vaccine, broadening the arsenal of drugs effective in the treatment and prevention of COVID-19 disease remains critical in the global effort to control the SARSCoV2 pandemic. Opioids and opioid antagonists may have a role in treating and in the prevention of this disease based on a number of observations: an unexpectedly low incidence of COVID-19 has been observed in patients treated for opioid dependency with long acting opioid drugs such as methadone; opioids bind to the ACE2 transmembrane protein, a molecule that is widely considered to be main host cell receptor for SARS CoV2 cell entry; opioids have systemic immunomodulatory effects which may influence the response to the virus; studies aimed at repurposing drugs for treatment of COVID-19 have identified that opioids have therapeutic potential and finally there are ongoing trials of some of these drugs. The interaction of long acting opioids or opioid antagonists with the ACE2 receptor and the possible effects on TLR4 function in SARS CoV2 infection should be given serious consideration when developing effective therapies.
ARIA-EAACI statement on severe allergic reactions to COVID-19 vaccines -- an EAACI-AR...
Ludger Klimek
Marek  Jutel

Ludger Klimek

and 16 more

December 28, 2020
Coronavirus disease 2019 (COVID-19) vaccine BNT162b2 received approval and within the first few days of public vaccination several severe anaphylaxis cases occurred. An investigation is taking place to understand the cases and their triggers. The vaccine will be administered to a large number of individuals worldwide and concerns raised for severe adverse events might occur. With the current information, the European Academy of Allergy and Clinical Immunology (EAACI) states its position for the following preliminary recommendations that are to be revised as soon as more data emerges. To minimize the risk of severe allergic reactions in vaccinated individuals, it is urgently required to understand the specific nature of the reported severe allergic reactions, including the background medical history of the individuals affected and the mechanisms involved. To achieve this goal all clinical and laboratory information should be collected and reported. Mild and moderate allergic patients should not be excluded from the vaccine as the exclusion of all these patients from vaccination may have a significant impact on reaching the goal of population immunity. Health care practitioners vaccinating against COVID-19 are required to be sufficiently prepared to recognise and treat anaphylaxis properly with the ability to administer adrenaline. A mandatory observation period after vaccine administration of at least 15 minutes for all individuals should be followed. The current guidelines, which exclude patients with severe allergies from vaccination with BNT162b2, should be re-evaluated after more information and experience with the new vaccine develops.
Maintenance of neutralizing SARS-CoV-2 antibodies over five months in convalescent SA...
Sissy Sonnleitner
Martina Prelog

Sissy Sonnleitner

and 12 more

December 11, 2020
Level and duration of protective immunity against SARS-CoV-2 after primary infection is of crucial importance for preventive approaches. In order to provide evidence for the longevity of specific antibodies, we investigated the generation and maintenance of neutralizing antibodies of convalescent SARS-CoV-2-afflicted patients over a five month period post primary infection using an immunofluorescence assay, a commercial chemiluminescent immunoassay and an in-house enzyme-linked plaque-reduction neutralization assay. We present the successful application of an improved version of the plaque-reduction neutralization assay, which can be analyzed optometrically, significantly simplifying the interpretation of the results. Based on the results of the plaque-reduction neutralization assay, neutralizing antibodies were maintained in 85.3% of convalescent individuals without significant decay over five months. Furthermore, a positive correlation between severity of infection and neutralizing titer was shown. In conclusion, SARS-CoV-2-afflicted individuals have been proven to be able to establish and maintain neutralizing antibodies over a five months’ period after primary infection which allows to hope for long-lasting presumably protective humoral immunity after wild-type infection or even after vaccination.
Neurological signs in African swine fever virus-infected piglets
Ngoc Hai Nguyen
Trung Quan Nguyen

Ngoc Hai Nguyen

and 5 more

December 10, 2020
African swine fever (ASF) has circulated in Viet Nam since 2018, causing significant loss to the pig industry. The clinical signs of the ASFV-infected piglets have not been well documented. This is the first report of neonate piglets with neurological signs. ASFV was detected in brain tissues by PCRs and IHC. Also, CSF, PPV, PRRSV were not detected by PCRs suggesting that the ASFV might be the cause of neurological signs in piglets. It is recommended that brain tissues should be used in the ASFV detection in piglets, especially in neurological cases.
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