SARS-CoV-2 outbreak: role of viral proteins and genomic diversity in virus infection and COVID-19 progression.

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is the cause of coronavirus disease 2019 (COVID-19); a severe respiratory distress that has emerged from the city of Wuhan, Hubei province, China during December 2019. COVID-19 is currently the major global health problem and the disease has now spread to most countries in the world. COVID-19 has profoundly impacted human health and activities worldwide.

Genetic and morphological characterization of a new genotype of nervous necrosis virus circulating among Nile tilapia in the south of Egypt.

Nervous necrosis virus (NNV) is the causative agent of viral nervous necrosis in freshwater and marine fishes. In this study, NNV circulating among wild and farmed Nile tilapia (Oreochromis niloticus) was genetically and morphologically characterized using reverse transcription polymerase chain reaction (RT-PCR), sequencing analysis, and transmission electron microscopy (TEM). Brain, eye, and other organ (spleen, kidney, heart, and liver) specimens were collected from 87 wild (66) and farmed (21) Nile tilapia fish during their adult or juvenile stage at different localities in Qena and Sohag governorates in southern Egypt.

Active Surveillance and Genetic Characterization of Prevalent Velogenic Newcastle Disease and Highly Pathogenic Avian Influenza H5N8 Viruses Among Migratory Wild Birds in Southern Egypt During 2015-2018.

A total of 1007 samples (910 fecal droplets and 97 cloacal swabs) were collected from 14 species of migratory wild birds in most wetlands during 3 successive migration seasons from September to March (2015-2018) in Southern Egypt. The samples were propagated in embryonated chicken eggs and positive allantoic fluids by hemagglutination test were tested for Newcastle disease virus (NDV) and avian influenza virus (AIV) prevalence using RT-PCR and specific primers targeting the NDV fusion (F) and AIV matrix genes. Further subtyping of the AIV hemagglutinin (HA) and neuraminidase (NA) was conducted, and representative isolates were selected and sequenced for full F gene of NDVs and HA and NA genes of the AIV.

Human Wharton's Jelly Mesenchymal Stem Cells Secretome Inhibits Human SARS-CoV-2 and Avian Infectious Bronchitis Coronaviruses.

Human SARS-CoV-2 and avian infectious bronchitis virus (IBV) are highly contagious and deadly coronaviruses, causing devastating respiratory diseases in humans and chickens. The lack of effective therapeutics exacerbates the impact of outbreaks associated with SARS-CoV-2 and IBV infections. Thus, novel drugs or therapeutic agents are highly in demand for controlling viral transmission and disease progression.

Vaccine Quality Is a Key Factor to Determine Thermal Stability of Commercial Newcastle Disease (ND)Vaccines.

Vaccination against Newcastle disease (ND), a devastating viral disease of chickens, is often hampered by thermal inactivation of the live vaccines, in particular in tropical and hot climate conditions. In the past, "thermostable" vaccine strains (I-2) were proposed to overcome this problem but previous comparative studies did not include formulation-specific factors of commercial vaccines. In the current study, we aimed to verify the superior thermal stability of commercially formulated I-2 strains by comparing six commercially available ND vaccines.

Molecular characterisation of rabies virus detected in livestock animals in the southern part of Egypt during 2018 and 2019.

Brain samples were collected from 33 animals of different species, including buffalo, cattle, dog, donkey, fox and wolf, that had been suspected to be infected by rabies virus (RABV) in different geographical regions of Aswan and Luxor governorates in Egypt. The samples were submitted for histopathological examination and the presence of the nucleic acid and antigens of RABV was tested by RT-PCR and indirect fluorescent antibody technique (IFAT), respectively. Sixteen samples were found positive by all the three examinations.

The seropervelance of infectious hepatitis viruses (HBV, HCV and HEV) among blood donors and their correlation to risk factors in Qena governorate, Upper Egypt.

This study was performed to determine the prevalence of HBV and HCV infection among blood donors and the occurrence of HEV in hepatitis viruses seropositive blood donors. Also, to investigate the correlation between the occurrence of hepatitis viruses and other risk factors (gender, age, occupation, educational level, residency and donors' types). A total of 11,604 blood samples from apparently healthy blood donors of age range 18-60 years old were collected.

Molecular characterization of full genome sequences of Newcastle disease viruses circulating among vaccinated chickens in Egypt during 2011-2013.

Although intensive vaccination programs have been implemented, Newcastle disease (ND) outbreaks, accompanied by severe economic losses, are still reported in Egypt. The genetic characterization of ND virus (NDV) strains isolated from ND-vaccinated chicken flocks provides essential information for improving ND control strategies. Therefore, here, 38 NDV strains were isolated and identified from outbreaks among vaccinated flocks of broiler chickens located in the provinces of Qena, Luxor, and Aswan of Upper Egypt during 2011-2013.

Molecular and biological characterization of the immunological potency of Newcastle disease virus oil emulsion-inactivated vaccines prepared from field isolate obtained from vaccinated chickens outbreak.

This study was conducted to characterize the immunological parameters of chickens vaccinated with two formulated inactivated vaccines, water in oil (WO) and water in oil in water (WOW), prepared from velogenic Newcastle disease virus (vNDV) genotype VIIj isolated from outbreak among vaccinated chickens. Six groups (G1-G6) of commercial broiler chickens were established (n = 20). The G1-G3 were received homologous (WO and WOW) and heterologous (LaSota) inactivated vaccines, respectively.

Genetic characterization of H5N2 influenza viruses isolated from wild birds in Japan suggests multiple reassortment.

Low-pathogenic avian influenza viruses (LPAIVs) of the H5 subtype can mutate to highly pathogenic forms, potentially destabilizing the poultry industry. Wild migratory birds are considered a natural reservoir of LPAIVs capable of dispersing both high- and low-pathogenic forms of the virus. Therefore, surveillance and characterization of AIV in wild birds are essential.

Genetic characterization of a rare H12N3 avian influenza virus isolated from a green-winged teal in Japan.

This study reports on the genetic characterization of an avian influenza virus, subtype H12N3, isolated from an Eurasian green-winged teal (Anas crecca) in Japan in 2009. The entire genome sequence of the isolate was analyzed, and phylogenetic analyses were conducted to characterize the evolutionary history of the isolate. Phylogenetic analysis of the hemagglutinin and neuraminidase genes indicated that the virus belonged to the Eurasian-like avian lineage.

Propagation of Asian isolates of canine distemper virus (CDV) in hamster cell lines.

Backgrounds: The aim of this study was to confirm the propagation of various canine distemper viruses (CDV) in hamster cell lines of HmLu and BHK, since only a little is known about the possibility of propagation of CDV in rodent cells irrespective of their epidemiological importance.

Methods: The growth of CDV in hamster cell lines was monitored by titration using Vero.dogSLAMtag (Vero-DST) cells that had been proven to be susceptible to almost all field isolates of CDV, with the preparations of cell-free and cell-associated virus from the cultures infected with recent Asian isolates of CDV (13 strains) and by observing the development of cytopathic effect (CPE) in infected cultures of hamster cell lines.

The Asia 2 specific signal peptide region and other domains in fusion protein genes characterized Asia 1 and Asia 2 canine distemper viruses.

Background: Although the presence of Asia 2 group of canine distemper virus (CDV) was known by the sequencing and phylogenetic analysis of hemagglutinin (H) gene, the fusion (F) protein gene sequence of Asia 2 group had not been identified. So, the sequence analysis of F gene was carried out to elucidate the genotypic varaitons among Asian isolates.

Results: The phylogenetic analysis of F and H gene sequences from fourteen CDV isolates obtained from diseased dogs in Japan and Thailand indicated that the F genes had a new initiation codon and extra 27 nucleotides upstream of the usual open reading frame (ORF) and the F proteins had extra 9 amino acids at the N-terminal position only in Asia 2 isolates.