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Please note: These are preprints and have not been peer reviewed. Data may be preliminary.
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.
African Swine Fever spread across Asia, 2018---2019
Michael Ward
Ellen Mighell

Michael Ward

and 1 more

December 08, 2020
African Swine Fever Virus (ASFV) is a highly contagious pathogen causing disease in pigs, commonly characterised by acute haemorrhagic fever. Prior to August 2018, African Swine Fever (ASF) had not been reported in Asia, but has since spread throughout China, Mongolia, Korea, Vietnam, Laos, Cambodia, Myanmar, the Philippines, Hong Kong, Indonesia, Timor-Leste and Papua New Guinea. Using data collated from reports of confirmed cases, we applied spatio-temporal analysis to describe ASFV spread throughout Asia, from 1 August 2018 (reported start date) to 31 December 2019. Analysis revealed a propagating epidemic of ASFV throughout Asia, with peaks corresponding to increased reports from China, Vietnam and Laos. Two clusters of reported outbreaks were found. During the epidemic, ASFV primarily spread from the North-East to the South-East: a larger, secondary cluster in the North-East represented earlier reports, whilst the smaller, primary cluster in the South-East was characterised by later reports. Significant differences in country-specific epidemics, morbidity, mortality and unit types were discovered, likely attributable to differences in prevention, surveillance and control measures. The initial number of outbreaks and enterprise size are likely predictors of the speed of spread and the effectiveness of ASFV stamping out procedures. Biosecurity methods, wild boar populations and the transportation of pigs and movement of infected fomites are discussed as likely risk factors for facilitating ASFV spread across Asia.
Isolation and characterization of a mammalian orthoreovirus type 3 in a fecal sample...
Wenjing Zhang
Michiyo Kataoka

Wenjing Zhang

and 9 more

November 30, 2020
Mammalian orthoreoviruses (MRVs) have been identified in various mammalian species, including humans, bats, and pigs. However, MRV isolation and complete genome sequences from wild boars have not yet been reported. In this study, we isolated, sequenced, and analyzed an MRV from a free-living wild boar in Japan using a porcine sapelovirus-resistant cell line N1380. The complete and empty virus particles were obtained from the N1380 cell culture supernatants, and complete genome sequences were obtained from complete virus particles. Sequence analyses revealed that the isolated MRV, named TY-14, was classified as MRV3 and had a close genetic relationship with lion in a Japanese zoo MRV2 (L2, L3, and M3 genes) and human MRV2 from Japan (S2 gene). Phylogenetic analyses showed that TY-14 clustered only with bat MRVs in the M1 gene, while TY-14 formed a cluster with several animal MRVs in the M2 and S3 genes, and independently branched in the L1, S1, and S4 genes, suggesting a genetic relationship with other unknown origins. Recombination events were identified in the M2 gene. These results suggest that TY-14 was generated by reassortment and recombination events involving MRVs circulating in Japan, bats, and other unknown origins.
Clinical, laboratory and chest computed tomography aspects of hospitalized patients w...
ali sharifpour
sepideh Safanavaei

ali sharifpour

and 11 more

November 30, 2020
The clinical symptoms, blood laboratory data, O2 saturation and high resolution computed tomography (HRCT) findings are critical factors in diagnosis of COVID-19 infection. In this study, 105 hospitalized patients suspected of having COVID-19 were evaluated. Finally, the data of 83 confirmed cases by HRCT and RT-PCR were analyzed. 61.40% of the patients had a comorbidity disease. 89.20% had fever, 92.00% cough, 91.40% dyspnea. Abnormal CRP seen in 77.80% of the patients following by 66.70% lymphopenia, and 60.30% neutrophilia. Also, ALP (abnormal vs. normal) and score of HRCT assessment variables had a significant effect on the positiveness of HRCT findings. 87.95% had abnormal HRCT with 41% bilateral multilobar patchy ground glass opacity (GGO). Moreover, there was a statistically significant association between level of O2 saturation and HRCT results. Our findings showed that male patients with middle age and comorbidity disease were more susceptible to the COVID-19 infection. Additionally, clinical features, blood laboratory findings, O2 saturation and HRCT findings are critical factors in prognosis of COVID-19 infection.
BEST DRUG INTERACTION FOR COVID-19 THERAPEUTIC MANAGEMENT: A METANALYSIS
Maria Gabriela Farias
Wesley Conceição

Maria Gabriela Farias

and 5 more

November 27, 2020
Background and Purpose: The Covid-19 is a viral infection classified as a pandemic by the World Health Organization. There is not currently therapy against the Sars-cov-2. We aimed to assess the best drug therapy approach for the management of Covid-19. Experimental Approach: We did a systematic review and meta-analysis of randomized controlled trials of drugs used in patients with Covid-19. We performed research in the PubMed and the Medrxiv. The trials were included if the patients were over 12 years old, diagnosed through the rt-PCR test and who assessed as primary outcomes or decreased mortality, or time to clinical improvement, or hospitalization time. Random-effects meta-analysis was used to pool individual studies. Heterogeneity was assessed using I². The review has been registered on PROSPERO, number 179879. Key Results: Nine trials were included for analysis. Remdesivir, mainly early after the onset of symptoms, led to a reduction in mortality (OR, 0·85; 95% CI, 0·05 to 0·98; P=0·045). Although this meta-analysis did not observe a reduction using dexamethasone, the Recovery Trial indicates that it can be an option for a patient that needs oxygen support. Our study did not demonstrate the efficacy of any treatment to minimize the effects of Covid-19 related to large hospital stay or time to clinical improvement. Conclusion and Implications: Remdesivir is the only drug that can change the course of Covid-19, reducing mortality rates. Despite this result, other studies must evaluate the effectiveness of this and other drugs in the management of Covid-19 mainly studies with robust methods.
COVID-19: Animal Epidemiology and Zoonotic risk
Maurizio Ferri
Shin Jie  Yong

Maurizio Ferri

and 1 more

November 26, 2020
The COVID-19 pandemic represents one of the greatest public health crises in recent history that caused unprecedented and massive disruptions of social and economic life globally. It is widely acknowledged that bats are the animal reservoir of coronavirus 2 of the severe acute respiratory syndrome (SARS-CoV-2), the causative agent of the human coronavirus disease 2019 (COVID-19). It has also long been known that coronaviruses circulate among different animal species. However, much remain to be understood of the epidemiology, the presumed existence of intermediate animal species and current and potential animal routes of SARS-Cov-2 transmission to humans. The recent observational and experimental studies also highlight the role of domestic and farmed animals in the epidemiology of COVID-19. This raises concerns of the potential spread of infection among susceptible animal species, with the risk of evolving into panzootic, and the likely occurrence of anthropozoonoses or reverse zoonosis (from humans to animals). As for other wildlife emerging pathogens, the animal-human spillover of SARS-CoV-2 is linked to a closer interface with humans, with the resulting risk of a pandemic. This knowledge has meaningful implications for the design of effective wildlife animal surveillance (epidemic intelligence) targeting CoVs in animal reservoirs, and requires the mobilization of different lines of expertise, notably veterinary epidemiologists and virologists, within a multi-disciplinary approach according to the One-Health principles.
Genomic and antigenic properties of Newcastle Disease virus genotypes 2.XX1 and 2.VII...
Mahmoud Naguib
Dirk Höper

Mahmoud Naguib

and 11 more

November 26, 2020
Newcastle disease (ND), caused by avian orthoavulavirus type-1 (NDV), is endemic in poultry in the Middle East causing continuing outbreaks in poultry populations despite efforts to vaccinate. In the past, genotype 2.XXI (former 2.VI) was present in poultry in Egypt but has been replaced by genotype 2.VII. We investigated whether virus evolution contributed to superseding, and focused on the antigenic sites within the Heamagglutinin-Neuramindase (HN) spike protein. Full length sequences of a NDV genotype 2.VII isolate currently circulating in Egypt was compared to a genotype 2.XXI isolate that was present as co-infection with vaccine type viruses (2.II) in an historical isolate of the year 2011. Amino acid differences in the HN glycoprotein for both 2.XXI and 2.VII viruses amounted to 11,7% and 11,9 % compared to LaSota vaccine type. However, mutations within the globular head (aa 126-570), bearing relevant antigenic sites, were underrepresented (aa divergence of 8,8% and 8,1 % compared to 22,4% and 25,6% within the fragment encompassing cytoplasmic tail, transmembrane part and stalk regions (aa 1-125) for genotypes 2.XXI and 2.VII, respectively. Nevertheless, reaction patterns of HN-specific monoclonal antibodies revealed differences between vaccine type viruses and genotype 2.XXI and 2.VII viruses for specific epitopes. Accordingly, compared to Egyptian vaccine type isolates and the LaSota vaccine reference strain, single aa substitutions in 6 of 10 described neutralizing epitopes were found within the attachment protein. However, the same alterations in neutralization sensitive epitopes were present in old genotype 2.XXI as well as in newly emerged genotype 2.VII isolates. In addition, isolates were indistinguishable by polyclonal chicken sera raised against different genotypes including vaccine viruses. These findings suggest, that factors other than antigenic differences within the HN-protein account for facilitating spread of genotype 2.VII while displacing genotype 2.XXI viruses in Egypt.
African swine fever virus DNA detection in commercial pig feed and feed ingredients i...
Zhichun Yan
Yakuan Huang

Zhichun Yan

and 3 more

November 25, 2020
During the acute phase of the African Swine Fever Virus (ASFV) epidemic in China, complete feed, and feed ingredients from three mills were tested for ASFV DNA by PCR. Across mills, the percentage of positive sample pools detected in complete feed ranged from 0.5% to 1.2%, and from 0.2% to 1.8% in feed ingredients, including positive pools of wheat, rice, corn, and soy samples. This is the first report of ASFV contamination in feed under commercial conditions in China.
Effectiveness and controversy of convalescent plasma therapy for COVID-19 patients
zhanjun Shu
xin Da

zhanjun Shu

and 4 more

November 19, 2020
Coronavirus disease2019(COVID-19) is a pandemic with no specific therapeutic agents and substantial mortality. It is critical to find new treatments. Convalescent plasma, donated by persons who have recovered from COVID-19, is the acellular component of blood that contains antibodies, including those that specifically recognize SARS-CoV-2. Therefore, for COVID-19 patients, Convalescent plasma, could prove lifesaving, such as improving the clinical symptoms, increasing the neutralizing antibody, decreasing the viral load , reducing the death rate, with safety and without seriously ADE. Meanwhile, it is urgent to perform large sample randomized controlled trials to confirm the transfusion timing, dosage, frequency and actively prevent adverse outcomes that may occur, establishing a standard procedure for treatment from convalescent plasma collection, preservation, transport, to transfusion.
Pan-genome analysis of coronaviruses derived from major of canine and feline
Hai Ha Pham Thi
Thanh Luan Nguyen

Hai Ha Pham Thi

and 1 more

November 19, 2020
Coronaviruses (CoVs) are a well-known cause of severe enteric, respiratory, and systemic disease in a wide range of animals and in humans. To understand the route of disease origin and viral transmission in companion animals, a comparative pan-genomic analysis of coronavirus sequences originating from major felines and canines were conducted. The average nucleotide identity (ANI) is a rapid procedure for assessing the very close antigenic relationship between feline CoV (FCoVs) and canine CoV (CCoVs) and ANI-based phylogenetic tree that clustered CoVs according to their respective host species. While pan-genomic analysis demarcated strains clearly. The distribution of the clinical isolates all across the categories in the hierarchical phylogenetic model enabled the visualization of their original ecological niche rather than their isolation source, as infections are extremely rare events and evolutionary dead-ends. In polymorphism analysis, we found seven accessory gene clusters common to the FCoV/CCoV category clade, including pantropic strains, that perform functions supporting their pathogenicity. In addition, the gene presence/absence among FCoVs and CCoVs would provide very valuable information on species-specific control measures against CoV disease, such as the selection of good markers for differentiating new species from common and/or pantropic isolates. Also, the virulent FCoV strains were grouped with human CoV strains NL63 and 229E confirming hypotheses stating that cats are highly susceptible to HCoVs, while dogs have low susceptibility to the virus. In conclusion, the combined analysis allows for better phylogenetic resolution and the implication of virus origins, recombination, and virus–host interaction, as well as biomarkers.
Risk factors and prevalence of porcine circovirus 2 and porcine reproductive and resp...
VASILEIOS PAPATSIROS
Georgios Papakonstantinou

VASILEIOS PAPATSIROS

and 6 more

November 16, 2020
The aim of the present study were to describe for first time the prevalence of porcine r porcine circovirus type-2 (PCV2) among pig farms. PIn conclusion, our results could be the basis of the development of surveillance protocols for a national monitoring system for PRRSV and PCV2, which could prevent future infection of Greek farms.
First genome sequencing of SARS-CoV-2 recovered from an infected cat and its owner in...
Renata Carlos
Ana Paula Melo Mariano

Renata Carlos

and 11 more

November 12, 2020
An 11 years-old male mixed-breed cat, with exclusively indoor life, presented 3 cough episodes after the owners tested positive by RT-PCR for SARS-CoV-2. The house is inhabited by 5 people (3 adults and 2 children), and 2 of the adults have shown mild symptoms associated with throat discomfort. The cat was vaccinated, had no history of any previous disease, and tested negative for Feline Coronavirus (FeCoV), Feline Immunodeficiency Virus (FIV) and Feline Leukemia Virus (FeLV). Rectal sample collected from the cat was positive for SARS-CoV-2 by RT-PCR. Viral genome sequences recovered from human and cat samples showed an average 99.4% sequence identity. This is the first report of genome sequences of SARS-CoV-2 recovered from a cat and its owner in Latin America.
The 6th amino acid mutation of Rep protein had no effect on PCV2b but enhanced PCV2d...
Xiaoyan Wu
Shuo Wang

Xiaoyan Wu

and 12 more

November 11, 2020
Porcine circovirus type 2 (PCV2) is the etiological agent that primary cause of post-weaning multisystemic wasting syndrome (PMWS). The major genotypes, PCV2a, PCV2b and PCV2d, are highly prevalent, but now replaced with 2b and 2d in swine population in worldwide. Rep protein is the key protein for viral replication. Compared a large number of Rep protein amino acid (aa) sequences, we found that there were three sites with regular changes between 2b and 2d.In order to analyze the effect of key sites on viral replication, we used site-directed mutagenesis to mutate the 6th aa of Rep (alternations with asparagine and serine) between PCV2b and PCV2d, Two wild-type and two mutant viruses infectious clones were rescued by non-contaminated porcine kidney-15 (PK-15) cells. Real-time quantitative PCR and a one-step growth curve were used to determine viral load to assess the replication of rescued viruses. The results showed that there was no significant difference between the PCV2b mutation and the wild-type PCV2b virus in vitro, while the mutation ofPCV2d enhanced viral replication.
First detection of porcine respirovirus 1 in Germany and in the Netherlands
Leonard Schuele
Erley Lizarazo

Leonard Schuele

and 12 more

November 10, 2020
PRV1 was first detected in deceased pigs from Hong Kong in 2013. It has since been detected in the USA, Chile and most recently in Hungary. Information on the pathogenicity and global spread is sparse, however it has been speculated to play a role in the porcine respiratory disease complex. In an effort to investigate the porcine virome, we screened 53 pig samples from 29 farms using SMg within the Dutch/German border region. In five farms we detected PRV1. qPCR confirmed the presence of the virus in 2 of these farms and found an additional 6 positive farms. Phylogenetic analysis found the closest match to the first detected PRV1 strain in Hong Kong. The Dutch/German region represents a major area of pig farming within Europe and could provide important information on the characterization and circulation of porcine viruses, such as PRV1. Together with the recent detection of PRV1 in Hungary, these findings suggest widespread of PRV1 in Central Europe, highlighting the need for further research on persistence, pathogenicity and transmission in Europe.
Prediction of COVID-19 cases using the weather integrated deep learning approach for...
Kantha Rao   Bhimala
GOPAL KRISHNA PATRA

Kantha Rao Bhimala

and 3 more

November 10, 2020
Advanced and accurate forecasting of COVID-19 cases plays a crucial role in planning and supplying resources effectively. Artificial Intelligence (AI) techniques have proved its capability in time series forecasting of the non-linear problems. In the present study, the relationship between weather factor and COVID-19 cases was assessed and also developed a forecasting model using long short term memory (LSTM), a deep learning model. The study found that the specific humidity has a strong positive correlation, whereas there is a negative correlation with maximum temperature and positive correlation with minimum temperature was observed in various geographic locations of India. The weather data and COVID-19 confirmed cases data (1st April-30th June 2020) was used to optimize univariate and multivariate LSTM time series forecast models. The optimized models were utilized to forecast the COVID-19 cases for the period 1st July 2020 to 31st July 2020 with 1 to 14 days of lead time. The results showed that the univariate LSTM model was reasonably good for the short term (1day lead) forecast of COVID-19 cases (relative error < 20%). Moreover, the multivariate LSTM model improved the medium-range forecast skill (1-7days) after including the weather factors. The study observed that the specific humidity played a crucial role in improving the forecast skill majorly in the West and northwest region of India. Similarly, the temperature played a significant role in model enhancement in the Southern and Eastern regions of India.
Molecular detection and phylogenetic analysis of pigeon circovirus in China during 20...
Haoran Wang
Hui Gao

Haoran Wang

and 6 more

November 09, 2020
The Pigeon circovirus (PiCV) which contains a circular single stranded DNA (approximately 2 kb) belongs to the genus Circovirus and the family Circoviridae. PiCV infections in pigeons (Columba livia) have been reported worldwide. Nowadays, pigeon racing is becoming increasingly popular and considered to be a national sport in China, and even, the greatest competitions of racing pigeons are stake place in China. However, there is no epidemiologic data on PiCV infections among racing pigeons in China. To trace the prevalence, genetic variation and evolution of PiCV in sick and healthy racing pigeons, 622 samples were collected from 11 provinces or municipalities of China from 2016 to 2019. Samples were tested by polymerase chain reaction. The results showed that the positive rate of PiCV was 19.3% (120/622) at the sample level; 59.0% (23/39) at the club level, suggesting that the virus was prevalent in Chinese racing pigeons. A sequence analysis revealed that the cap genes of the PiCV strains identified in our study display high genetic diversity and shared nucleotide homologies of 71.9%–100% and amino acid homologies of 71.7%–100%. 28 and 37 unique amino acid substitutions were observed among the cap proteins and rep proteins of our PiCV strains, respectively. Furthermore, two initiation codons (GTG and ATT) of cap gene were newly found. A cap-gene-based phylogenetic analysis showed that the strains in this study could be further divided into six groups (A, B, C, E, G, H and I) and some of our strains are closely related to worldwide strains from different types of pigeons. A large number of recombination events (31 events) were also detected in the PiCV genomes from Chinese racing pigeons. These findings suggest that PiCV strains circulating in China exhibits higher genetic diversity.
Canine distemper outbreak by natural infection in a group of vaccinated maned wolves...
Vicente Vergara-Wilson
Carlos Sanchez

Vicente Vergara-Wilson

and 10 more

November 07, 2020
Canine morbillivirus, also known as canine distemper virus (CDV) is one of the most important infectious diseases threat to the health and conservation of free ranging and captive wild carnivores. CDV vaccination using recombinant vaccines has been recommended for maned wolf (Chrisosyon brachyurus) after the failure of modified live vaccines that induced disease in vaccinated animals. However, there has been a lack of systematic evaluation about the response of this preventive protocol in zoo carnivores due to ethical reasons that do not approve vaccination trials with challenge in that species. Here we report a CDV outbreak in a captive population of maned wolf with an index case that was previously vaccinated with a recombinant vaccine. Five juveniles and one adult from a group of seven maned wolves housed in an outdoor exhibit died in April-May 2013 in a zoo in the Metropolitan Region, Chile. Clinical signs ranged from lethargy to digestive and respiratory signs. Diagnosis of CDV was confirmed by histopathology, antibody assays and viral molecular detection and characterization. The phylogenetic analyses of the nucleotide sequence of H gene of the CDV genome identified in the two positive samples suggest a close relation with the lineage Europe 1, commonly found South America and Chile. CDV infections in maned wolf have not been previously characterized. To the authors best knowledge is the first report of the clinical presentation of CDV in a canine species previously inmmunized with a recombinant vaccine. Further research will be necessary to understand the impact of CDV in wild maned wolf populations and new protocols (with boosters) that could improve the effectiveness of the recombinant vaccine against CDV in wild carnivores.
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