A simple and quick PCR based method for detection of Omicron variant of SARS-CoV-2

SARS-CoV-2 pandemic has changed the global landscape since last 2 years. Against many challenges posed by the COVID19 pandemic to the humanity, the pace of solutions created by mankind is exemplary; diagnostics, vaccines, alternate therapies to name a few. With a rapidly changing virus strain its early identification in the field can be a quick solution to trace the individuals and control the spread of new emerging variants of SARS-CoV-2. This paper describes PCR based quick method for differentiation of Omicron variant of SARS-CoV-2 from other variants. Timely identification of this new variant will enable better management of pandemic control in the population.

Inactivated vaccine against Aujeszky's disease

Background and Aim: The Aujeszky's disease, also known as Pseudorabies, remains one of the most problematic fulminant diseases in domestic animals, affecting the central nervous system. The study aimed to investigate the effect of an inactivated vaccine against Aujeszky's disease based on "Kordai" virus strain. Materials and Methods: To test the inactivation of the "Kordai" strain (grown by the roller method in VNK-21/13 cell culture with an infectious titer of at least 7.5 lg TCD50/ml) which is causative of Aujeszky's disease, next-generation teotropin and propolis preparations were used in concentrations of 0.1%, 0.08%, and 0.04%. Results: As a result of comparative studies on the optimization of parameters for inactivating the "Kordai" virus strain, it was established that teotropin is a more effective inactivant than propolis. At the same time, the optimal final concentration of teotropin for inactivation was 0.1%, along with a reaction medium temperature of 37°C, pH of 7.4-7.6, and duration of inactivation of 14 h. The titer of virus-neutralizing activity (VNA) of antibodies at the pH (neutralization reactions) in vaccinated sheep of 10-12 months of age was 7.5±0.3, Ig TCID50/ml (tissue culture infectious dose 50%), and 3.5±0.3 in the cell culture VNK-21/13 (culture of Syrian hamster kidney cells). Conclusion: To determine colostral immunity in newborn lambs, the method of metabolic status correction was used to vaccinate lambs obtained from immune sheep 4 months after birth. The results showed that lambs obtained from immune sheep had high VNA titers. A sustained immune response in vaccinated animals was obtained after double vaccination.

Akt plays differential roles during the life cycles of acute and persistent murine norovirus strains in macrophages

Akt (Protein kinase B) is a key signaling protein in eukaryotic cells that controls many cellular processes such as glucose metabolism and cell proliferation for survival. As obligate intracellular pathogens, viruses modulate host cellular processes, including Akt signaling, for optimal replication. The mechanisms by which viruses modulate Akt and the resulting effects on the infectious cycle differ widely depending on the virus. In this study, we explored the effect of Akt serine 473 phosphorylation (p-Akt) during murine norovirus (MNV) infection. p-Akt increased during infection of murine macrophages with acute MNV-1 and persistent CR3 and CR6 strains. Inhibition of Akt with MK2206, an inhibitor of all three isoforms of Akt (Akt1/2/3), reduced infectious virus progeny of all three virus strains. This reduction was due to decreased viral genome replication (CR3), defective virus assembly (MNV-1), or diminished cellular egress (CR3 and CR6) in a virus strain-dependent manner. Collectively, our data demonstrate that Akt activation increases in macrophages during the later stages of the MNV infectious cycle, which may enhance viral infection in unique ways for different virus strains. The data, for the first time, indicate a role for Akt signaling in viral assembly and highlight additional phenotypic differences between closely related MNV strains. Importance Human noroviruses (HNoV) are a leading cause of viral gastroenteritis, resulting in high annual economic burden and morbidity; yet there are no small animal models supporting productive HNoV infection, or robust culture systems producing cell culture-derived virus stocks. As a result, research on drug discovery and vaccine development against norovirus infection has been challenging, and no targeted antivirals or vaccines against HNoV are approved. On the other hand, murine norovirus (MNV) replicates to high titers in cell culture and is a convenient and widespread model in norovirus research. Our data demonstrate the importance of Akt signaling during the late stage of the MNV life cycle. Notably, the effect of Akt signaling on genome replication, virus assembly and cellular egress is virus strain specific, highlighting the diversity of biological phenotypes despite small genetic variability among norovirus strains. This study is the first to demonstrate a role for Akt in viral assembly.

Herpesviruses in Captive Chelonians in Europe Between 2016 and 2020

Herpesviruses are important pathogens in tortoises and turtles, yet little is known about the epidemiology of these viruses. We analyzed herpesviruses detected by PCR in samples from captive chelonians in Europe according to virus strain, host species, year and season in which the animal was tested, and country in which the animal was kept. A total of 4,797 samples submitted to a diagnostic laboratory in Europe between January 2016 and December 2020 were evaluated. Of these, 312 (6.50%) were positive for herpesviruses. The types most commonly found were testudinid herpesvirus (TeHV)1 (143 positive, 45.83%) and TeHV3 (153 positive, 49.04%), but also included TeHV2 (1 positive, 0.32%), TeHV4 (3 positive, 0.96%), Terrapene herpesvirus 1 (7 positive, 2.24%), Trachemys herpesvirus 1 (2 positive, 0.64%), and three previously undescribed herpesviruses (0.96%). Herpesviruses were detected in chelonians in the families Testudinidae, Emydidae, Geoemydidae, and in the suborder Pleurodira. Among the species for which 100 samples or more were available, the highest proportions of positive samples (positivity rates) were found in samples from Horsfield's tortoises (Testudo horsfieldii) (14.96%), and radiated tortoises (Astrochelys radiata) (14.05%). Among tortoises (Testudinidae), viruses were most often detected in the spring, while in emydid turtles (Emydidae) they were most often detected in the summer. A comparison of the positivity rates according to country showed significant differences, with the highest rate in samples from Italy (16.01%). This study indicated possible differences in herpesvirus positivity rates depending on host species, virus strain, year of sampling, season, and country of origin. It provides useful information in further understanding fluctuations in infection rates as well as in helping to guide decision making for herpesvirus diagnostics in chelonian patients. It also provides evidence for the international dispersal of herpesviruses with their hosts through international trade.

Complete Genome Sequence of Infectious Bronchitis Virus Strain JP/KH/64, Isolated in Japan

Here, we report the complete genome sequence of infectious bronchitis virus (IBV) strain JP/KH/64, which is the reference strain for the JP-I genotype in Japan. This information should be useful for an in-depth understanding of the evolution of the JP-I genotype.