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Patients with asthma are susceptible to viral respiratory infections, due to weakened cellular immunity, chronic airway inflammation, and some other reasons. In fact, asthma was found to be a comorbidity to the Middle East respiratory syndrome coronavirus infection. Moreover, some asthma therapies like systemic corticosteroids used to manage severe asthma were found to be associated with severe acute respiratory syndrome coronavirus (SARS-CoV) viremia in the previous pandemic. However, from the epidemiological studies conducted so far across the globe, asthma patients are not exceptionally susceptible to COVID-19 compared to the general public; as opposed to the association seen with chronic obstructive pulmonary disease, diabetes, hypertension, obesity, and other known comorbidities of COVID-19. The bases for this interaction are not adequately understood. However, the heterogeneity of asthma disease as it relates to its various endotypes, altered angiotensin-converting enzyme (ACE2) expression in the airways, effect of rhinoviral infections, and effect of inhaled corticosteroids and biological response modifiers (BRMs), are the proposed mechanisms behind this interaction. Increased activity of ADAM 17 as induced by interleukin-13 at apical portion of pneumocytes may be responsible for the shedding of ACE2 on asthmatic airways. Furthermore, inhaled corticosteroids may prevent the occurrence of acute lung injury and, hence, acute respiratory distress by transrepression of pro-inflammatory pathways and transactivation of anti-inflammatory pathways. The antiviral effects of some inhaled corticosteroids whose molecular targets are not known may involve downregulation and competitive binding to the chaperone proteins heat shock proteins 90 and 70 between glucocorticoid receptor and nucleoprotein of SARS-CoV-2. MEDLINE was searched for terms such as asthma and COVID-19, antiviral effects of inhaled corticosteroids, BRM, and mechanisms of asthma-COVID-19 interaction. The reference lists of the obtained articles were also searched for additional literature.

Contagious ecthyma (CE) is an infectious disease of small ruminants caused by a parapoxvirus of family Poxviridae subfamily Chordopoxvirinae. The disease is obviously distinguished by an establishment of scabby lesions and ulcerative formation on less hairy areas including muzzle, ears, nostril, and sometimes on genitalia. The disease is endemic in sheep and goats. The virus is transmissible to other ruminants and is a public health concern in humans. Although the disease is known as self-limiting, it may cause a significant economic threat and financial losses due to lower productivity in livestock production. Information with regard to the risk of the disease and epidemiology in most parts of the world is underreported. This paper aims to provide relevant information about the epidemiology of CE in selected regions of Europe, South America, North America, Asia, Africa, and Australia. An in-depth comprehension of virus infection, diagnoses, and management of the disease will enable farmers, researchers, veterinarians, abattoir workers, health personnel, and border controllers to improve their measures, skills, and effectiveness toward disease prevention and control, toward reducing unnecessary economic loss among farmers. A herd health program for significant improvement in management and productivity of livestock demands a well planned extension program that ought to encourage farmers to equip themselves with adequate skills for animal healthcare.

Summary Filopodia are thin finger‐like protrusions at the surface of cells that are internally occupied with bundles of tightly parallel actin filaments. They play significant roles in cellular physiological processes, such as adhesion to extracellular matrix, guidance towards chemo‐attractants and in wound healing. Filopodia were recently reported to play important roles in viral infection including initial viral attachment to host cells, cell surfing, viral trafficking, internalization, budding, virus release and spread to other cells in a form that would avoid the host immune system. The detailed virus‐host protein interactions underlying most of these processes remain to be elucidated. This review will describe some reported virus‐host protein interactions on filopodia with the aim of identifying potential new anti‐virus therapeutic targets. Exploring this research area may lead to the development of novel classes of anti‐viral therapeutics that can block signalling pathways used by the virus to trigger filopodia formation. Successful compounds would inhibit initial virus attachment, formation of filopodia, expression of putative virus binding protein, extracellular virus trafficking, and budding.

Objective This study investigated the suitability of siRNA targeting specific genes that cause inhibition of virus replication in vitro especially for the virus that capable of crossing placenta and we employed a novel transplacental rat cytomegalovirus that mimics infection in human. Methods Six unique siRNAs with three each targeting different regions of IE2 (ie2a, ie2b and ie2c) and DNA polymerase (dpa, dpb and dpc) were prepared and tested for antiviral activities. The efficacy as an antiviral was determined in in-vitro by measuring TCID50 virus titer, severity of virus-induced cytopathic effect (CPE), intracellular viral genome loads by droplet digital PCR, the degree of apoptosis in siRNA-treated cells and relative expression of viral mRNA in infected Rat Embryo Fibroblast (REF) cells. Findings Remarkably, the siRNAs: dpa, dpb and IE2b, significantly reduced virus yield (approximately >90%) compared to control group at day 18 post infection (p.i). Changes in CPE indicated that DNA polymerase siRNAs were capable of protecting cells against CMV infection at day 14 p.i with higher efficiency than GCV (at the concentration of 300 pmol). Gene expression analysis revealed a marked down regulation of the targeted DNA polymerase gene (73.9%, 96.0% and 90.7% for dpa, dpb and dpc siRNA, respectively) and IE2 gene (50.8%, 49.9% and 15.8% for ie2a, ie2b and ie2c siRNA, respectively) when measured by RT-qPCR. Intracellular viral DNA loads showed a significant reduction for all the DNA polymerase siRNAs (dpa: 96%, dpb: 98% and dpc:92) compared to control group (P Conclusion In conclusion, this study clearly highlighted the feasibility of RNAi as an alternative antiviral therapy that could lead to controlling the CMV infection.

Background Cytomegalovirus (CMV) is an opportunistic pathogen that causes severe complications in congenitally infected newborns and non-immunocompetent individuals. Developing an effective vaccine is a major public health priority and current drugs are fronting resistance and side effects on recipients. In the present study, with the aim of exploring new strategies to counteract CMV replication, several anti-CMV siRNAs targeting IE2 and DNA polymerase gene regions were characterized and used as in combinations for antiviral therapy. Methods The rat embryo fibroblast (REF) cells were transfected with multi siRNA before infecting with CMV strain ALL-03. Viral growth inhibition was measured by tissue culture infectious dose (TCID50), cytopathic effect (CPE) and droplet digital PCR (ddPCR) while IE2 and DNA polymerase gene knockdown was determined by real-time PCR. Ganciclovir was deployed as a control to benchmark the efficacy of antiviral activities of respective individual siRNAs. Results There was no significant cytotoxicity encountered for all the combinations of siRNAs on REF cells analyzed by MTT colorimetric assay (P > 0.05). Cytopathic effects (CPE) in cells infected by RCMV ALL-03 had developed significantly less and at much slower rate compared to control group. The expression of targeted genes was downregulated successfully resulted in significant reduction (P Conclusions In conclusion. The study demonstrated a tremendous promise of innovative approach with the deployment of combined siRNAs targeting at several genes simultaneously with the aim to control CMV replication in host cells.

Human cytomegalovirus (HCMV) is a beta herpesvirus that inflicts an active infection in the fetus and immunosuppressive patients. The virus encodes many proteins that work together with cellular factors to achieve virus replication. In addition to vaccines, antiviral drugs can be deployed to manipulate how the virus replicates and minimize its pathogenicity. The five antiviral drugs approved by the Food and Drug Administration (FDA) have shown adverse reactions and the antiviral drug resistance were reported. Hence, this warrants the need for urgent development of a novel antiviral drug. Detailed understanding of the virus replication steps and how cellular signals interact with these steps will be key for pharmacological developments of for anti HCMV drugs. This review summarized all the drugs that target the virus proteins and cell signals that mediate CMV replication.

Orf disease is known to be enzootic among small ruminants in Asia, Africa, and some other parts of the world. The disease caused by orf virus is highly contagious among small ruminant species. Unfortunately, it has been neglected for decades because of the general belief that it only causes a self-limiting disease. On the other hand, in the past it has been reported to cause huge cumulative financial losses in livestock farming. Orf disease is characterized by localized proliferative and persistent skin nodule lesions that can be classified into three forms: generalized, labial and mammary or genitals. It can manifest as benign or malignant types. The later type of orf can remain persistent, often fatal and usually causes a serious outbreak among small ruminant population. Morbidity and mortality rates of orf are higher especially in newly infected kids and lambs. Application of antibiotics together with antipyretic and/or analgesic is highly recommended as a supportive disease management strategy for prevention of subsequent secondary microbial invasion. The presence of various exotic orf virus strains of different origin has been reported in many countries mostly due to poorly controlled cross-border virus transmission. There have been several efforts to develop orf virus vaccines and it was with variable success. The use of conventional vaccines to control orf is a debatable topic due to the concern of short term immunity development. Following re-infection in previously vaccinated animals, it is uncommon to observe the farms involved to experience rapid virus spread and disease outbreak. Meanwhile, cases of zoonosis from infected animals to animal handler are not uncommon. Despite failures to contain the spread of orf virus by the use of conventional vaccines, vaccination of animals with live orf virus is still considered as one of the best choice. The review herein described pertinent issues with regard to the development and use of potential effective vaccines as a control measure against orf virus infection.

Contagious ecthyma (Orf) is a viral skin condition caused by a parapoxvirus. It results in cutaneous lesions that destroy the hides and skin of the infected host. In this study, the pathogenicity of Malaysian isolates of Orf virus (UPM 1/14 and UPM 2/14) was evaluated in a rat model using different inoculation sites with/without dexamethasone administration. A total of 50 rats were used in this study. For the first part of the study, 35 rats were divided into three groups; group 1 (n = 15) was inoculated with 0.5 mL of UPM 1/14 (tissue culture infective dose 50% (TCID50) 108.1/mL) while group 2 (n = 15) was inoculated with 0.5 mL of UPM 2/14 (TCID50 107.2/mL) each at the dorsum (n = 5), ear pinna (n = 5), and labial commissure (n = 5). Group 3 (n = 5) served as the control and was administered 0.5 mL of phosphate-buffered saline in all the sites mentioned above. In the second study, 15 rats were divided into three groups: a dexamethasone group (n = 5) which was given 10 mg/kg of dexamethasone once daily for 3 days, a non-dexamethasone group (n = 5), and a control (n = 5). Intradermal inoculation of 0.5 mL of UPM 1/14 was administered to each rat in the dexamethasone and non-dexamethasone groups at the dorsum, ear pinna, and labial commissure, respectively. Clinical signs and histopathological changes were evaluated for 14 days post inoculation for the first experiment and 7 days for the second experiment. Mild hyperemia was observed in the dorsum, ear pinna, and labial commissures of all inoculation groups. Group 1 (ORFV UPM 1/14) had a higher (P 0.05) in the mean thickness of the stratum basale of the ear pinna and labial commissure between the dexamethasone and non-dexamethasone groups. Orf virus was detected by PCR from the skin tissues of rats with lesions using F1L and B2L viral genes. In conclusion, Malaysian isolates of Orf virus were seen to be mildly pathogenic to rats. The difference in inoculation sites and the induction of immune suppression were observed to present varying pathological responses in rats.

Orf is an infectious disease that affects the skin of sheep and goats resulting in lesions that reduce animal productivity. This study was aimed to determine the status of orf infection among small ruminants from selected farms in the state of the Selangor based on IgM antibody detection. Serum samples were collected from 90 goats and 90 sheep and subjected to qualitative enzyme-linked immunosorbent assay (ELISA) to measure IgM antibodies followed by chi-square analysis of the data. The result from this study showed that 33 goats (36.7%) and 7 sheep (7.8%) were positive for orf IgM antibodies, indicating higher seroprevalence among goats as compared to sheep. The risk factors such as species, breed, farm location, and history of orf, age, gender, presence of clinical signs, and farm location were shown to significantly affect the seropositivity of IgM antibodies in these species. In conclusion, this study showed that a significant number of goat populations in Selangor, Malaysia, harbor active orf infection in comparison to sheep.

Additional file 1: Figure S1. Standard curve and amplification curve of the siRNAs and GAPDH were determined from tenfold serial dilution of RNA isolated from treated cells. Figure S2. The cytotoxicity of combinations siRNA targeting RCMV ALL-03 and negative control siRNA in REF cells. Cells were transfected with lipofectamine 3000 and siRNA complex, which were prepared in final concentration of 300 pmol of siRNA and incubated for 6 h and an additional of 24/48/72 h at 37℃. The cellular viability was measured by MTT assay. Each treatment was performed in triplicate and repeated in two independent experiments. Results represent Mean ± Standard deviation. Figure S3. Gating references used for unstained, PI and FITC apoptosis analysis using flow cytometry. Figure S4. 1D ddPCR analysis plot shows detection of RCMV ALL-03 DNA in siRNA treated and non-treated groups. Each sample was partitioned into an average of 10,000 droplets per well and replicated in two wells. The droplet counts for positive (blue) and negative (gray) from all replicated wells were combined to yield a “merged” well. A fluorescence amplitude value > 1176 (pink line) was considered to be a positive droplet.

There is a little information on the characterization of Orf virus strains that are endemic in Malaysia. The relationship between the severity of disease and the molecular genetic profile of Orf virus strains has not been fully elucidated. This study documented the first confirmed report of contagious ecthyma causing by Orf virus in goats from a selected state of eastern peninsular Malaysia. The disease causes significant debilitation due to the inability of affected animals to suckle which brings a great economic loss to the farmers. A total of 504 animals were examined individually to recognize the affected animals with Orf lesion. Skin scrapping was used to collect the scab material from the infected animals. The presence of Orf virus was confirmed by combination of methods including virus isolation on vero cells, identification by Transmission Electron Microscopy (TEM) and molecular technique using PCR and Sanger sequencing. The results showed the successful isolation of four Orf virus strains with a typical cytopathic effects on the cultured vero cells line. The morphology was confirmed to be Orf virus with a distinctive ovoid and criss cross structure. The phylogenetic analysis revealed that these isolated strains were closely related to each other and to other previously isolated Malaysian orf viruses. In addition these Orf virus strains were closely related to Orf viruses from China and India. This study provides more valuable insight in terms of genotype of Orf virus circulating in Malaysia.

Orf virus is a DNA virus that causes contiguous ecthyma in goat and sheep. Infection of animals with this virus cause high mortality in young animals resulting in huge economic losses. In this study, we investigated an outbreak of Orf in a goat farm in Malaysia. Samples were collected from infected animals and viral isolation was done using both LT and MDCK cell lines. Molecular detection was done by conventional PCR for specific primers; B2L and F1L genes and phylogenetic analysis was done on the sequence data obtained. Cytopathic effects (CPE) were observed in both cell lines after 3 days of inoculation and were 50 % by the sixth day. PCR showed positive bands for both B2L and F1L genes and phylogenetic analysis showed that the Malaysian strain had close homology to the Chinese and Indian Orf virus isolates. This study gives more insight into the existing Orf viral strains in Malaysia and their relationship with other strains globally.

Next generation sequencing technologies has revolutionized genomic research by producing a large volume of sequence data and lowest per base cost compared to the traditional sanger method. Although this technology offers many advantages, gap occurrences are commonly found in draft assemblies. The same problem was observed with Rat Cytomegalovirus (RCMV) ALL-03 (Malaysia strain), where a complete genome sequence could not produce the complete genome due to the presence of gaps in the draft genome. This restrains our ability to take full advantage of genome data. This study aimed to identify the sequence data present in the gap regions and close these gaps in order to produce a complete genome sequence for RCMV ALL-03. Twenty sets of specific primers were designed between two adjacent contigs and PCR was carried out to obtain the appropriate sequences in respective gap regions. Sanger sequencing was employed in the PCR product to get the gap sequences. Out of the five identified gaps in the RCMV ALL-03 genome sequence, only three were confirmed to be true gaps, while the other two were due to sequence repeats. In conclusion, all the gaps were closed successfully and complete genome sequence of RCMV ALL-03 can now be explored in further studies.

Orf is a clinical manifestation of parapoxvirus infection often fatal in goats and sheep especially when they are under stress or influenced by unfavorable environment. This study investigated the pathogenicity of two Orf virus isolates (ORFV UPM1/14 and UPM2/14) and host response in mouse model by using different inoculation sites with/without prior exposure to dexamethasone. Treatments with dexamethasone served as an immunosuppressant that may mimic stress situation in affected animals. Groups of five mice were given intradermal injection of 0.2 mL of tissue culture infective dose 50 (TCID50) of UPM1/14 (Group 1) and UPM2/14 (Group 2) at the dorsum (Group 1A; Group 2A), ear pinna (Group 1B; Group 2B), and labial commissure (Group 1C; Group 2C). An inoculum 0.2 mL of UPM1/14 was administered to animals treated with dexamethasone (n=5; 5 mg/kg/day intraperitoneally) and nondexamethasone (n=5) groups at the dorsum, ear pinna, and labial commissure. No significant difference (p>0.05) was observed in the mean lesion scores among the groups of different inoculation sites or between dexamethasone-treated and nontreated groups. However, there was a significant difference (p

The common physical and chemical methods for controlling rat pest are less than satisfactory and inhumane. Immunocontraception approach has been considered more humane and it can be accomplished by inducing the relevant host immune response that block further development of reproductive gametes. ZP3 proteins are known to play very important role during sperm-ovum fertilization. It is a self-antigen and only localized in female ovaries. Therefore, an immunization with ZP3 protein elsewhere will induce a generalize host immune response against ZP3 protein. This study employed rat ZP3 (rZP3) gene prepared from its cDNA of Rattus rattus diardii. It was delivered and expressed in vivo by naked plamid DNA (DrZP3) or recombinant ZP3-Adenovirus (Ad-rZP3). Expression studies in vitro with DrZP3 or Ad-ZP3 showed rZP3 proteins were successfully expressed in Vero cells. Hyperimmune serum against rZP3 that were prepared by immunizing several rats with purified rZP3-pichia yeast fusion protein showed it blocked sperms from binding DrZP3-transfected Vero cells. Female Sprague Dawley rats immunized with DrZP3 demonstrated a long-term effect for significant reduction of fertility up to 92.6%. Ovaries from rats immunized with DrZP3 were severely atrophied with disappearance of primordial follicles from ovarian cortex with an increased in the amount of oocyte-free cell clusters. Female rats immunized with Ad-rZP3 demonstrated 27% reduction of fertility. The infertility induced by Ad-rZP3 is comparatively low and ineffective. This could be due to a strong host immune response that suppresses the recombinant virus itself resulted in minimum rZP3 protein presentation to the host immune system. As a result, low antibody titers produced against rZP3 is insufficient to block oocytes from maturity and fertilization. Therefore, immunization with DrZP3 for immunocontraception is more effective than Ad-rZP3 recombinant adenovirus. It is proposed to explore further on the use of adenovirus or other alternative viruses to deliver ZP3 protein and for the development of enhanced expression of rZP3 in target host.

Toxoplasmosis is a cosmopolitan infection caused by an obligate intracellular protozoan, Toxoplasma gondii . The parasite was described as the most successful having full potentials to be transmitted through various routes from contamination of the environment and food substances to continuous spread as tissue cyst in meat, among its intermediate host, bypassing its sexual stage of life cycle in its definitive host. Relevant English databases were searched for the prevalence studies conducted in Nigeria. In this review, we identified the various ways through which the infection can be spread within human population as reported by various studies in Nigeria. Keywords: cosmopolitan, environment, intracellular, protozoan, toxoplasmosis

Background Rat cytomegalovirus ALL-03 (Malaysian strain) which was isolated from a placenta and uterus of a house rat, Rattus rattus diardii has the ability to cross the placenta and infecting the fetus. To further elucidate the pathogenesis of the Malaysian strain of Rat Cytomegalovirus ALL-03 (RCMV ALL-03), detailed analysis on the viral genome sequence is crucial. Methods Genome sequencing of RCMV ALL-03 was carried out in order to identify the open reading frame (ORF), homology comparison of ORF with other strains of CMV, phylogenetic analysis, classifying ORF with its corresponding conserved genes, and determination of functional proteins and grouping of gene families in order to obtain fundamental knowledge of the genome. Results The present study revealed a total of 123 Coding DNA sequences (CDS) from RCMV ALL-03 with 37 conserved ORF domains as with all herpesvirus genomes. All the CDS possess similar function with RCMV-England followed by RCMV-Berlin, RCMV-Maastricht, and Human CMV. The phylogenetic analysis of RCMV ALL-03 based on conserving genes of herpes virus showed that the Malaysian RCMV isolate is closest to RCMV-English and RCMV-Berlin strains, with 99% and 97% homology, respectively. Similarly, it also demonstrated an evolutionary relationship between RCMV ALL-03 and other strains of herpesviruses from all the three subfamilies. Interestingly, betaherpesvirus subfamily, which has been shown to be more closely related with gammaherpesviruses as compared to alphaherpesviruses, shares some of the functional ORFs. In addition, the arrangement of gene blocks for RCMV ALL-03, which was conserved among herpesvirus family members was also observed in the RCMV ALL-03 genome. Conclusion Genomic analysis of RCMV ALL-03 provided an overall picture of the whole genome organization and it served as a good platform for further understanding on the divergence in the family of Herpesviridae.

Over the last few years, the increase in the number of multi-resistant (MR) enterobacteria has become a major clinical problem. This study detects the occurrence and prevalence of Metallo betalactamase production among some clinical bacterial isolates in Murtala Muhammad Specialist Hospital, Kano and Al-Madina Specialist Hospital Kaduna, Nigeria. A total of 200 clinical isolates comprising of E. coli (83), Klebsiella pneumoniae (52), Pseusomonas aeruginosa (28) and Proteus mirabilis (37) were screened phenotypically for carbapenemase and specifically for Metallo betalactamase using Modified Hodges Test and EDTA Disc Synergy Test respectively. The result showed that 67(33.5%) of the isolates were found to produce carbapenemase. High production occurred in 24(35.8%) and low production occurred in 43(64.2%) of the isolates. Highest prevalence of carbapenemase was found in Pseudomonas aeruginosa (38.55%) followed by E. coli (34.8%), Proteus mirabilis. (29.1%) and least prevalence in Klebsiella pneumoniae (25.0%). The prevalence of MBLs in the study was 24.5% with highest prevalence in E. coli (31.32%) followed by Proteus mirabilis. (21.6%), Pseudomonas aeruginosa (21.2%) and least among Klebsiella pneumoniae. (14.3%). Most of carbapenemase producers produce MBL type. Urine samples were found to be with the highest prevalence of 38.3% when compared with ear swab (12.0%). Prevalence of 67.9% and 76.9% were recorded for Murtala Muhammad specialist hospital Kano and Al-madina hospital Kaduna respectively. This showed that carbapenemase-mediated resistance occurred in the selected hospitals and uncontrolled spread may lead to treatment failure and frustration. Keywords : Metallobetalactamase, Carbapenemase, Enterobacteriaceae, prevalence, Hospital

Hepatitis C virus (HCV) infection afflicts more than 170 million people worldwide, with the great majority of patients having acute hepatitis C later developing into chronic HCV infection. 320 participants (80 in each of four blood banks from Wudil, Gaya, Sumaila and Takai Local Government Areas (LGA)) were tested for antibodies to HCV. Out of a total of the 320 subjects, 319 were males and 1 female between the ages of 14 to 54 years. Third-generation enzyme–linked immunosorbent assay was used in the analysis. 16 out of the 320 were reactive, representing 5.0% of the total population studied. This showed a high prevalence of HCV infection among blood donors in this part of the country when compared with those established for western countries. Prevalence rate based on the 80 subjects in each LGA indicated Gaya and Wudil to have highest prevalence of 5(6.3%) each, followed by Sumaila with 4(5.0%). Takai was observed to have the least prevalence rate of 2(2.5%). The relationship between the demographic data with HCV infection revealed no statistical significance (P > 0.05). However, the relationship between possible risk factors and HCV infection revealed significant statistical association in the transmission through family (vertical transmission), receipt of injection as well as consumption of alcohol. Other possible risk factors such as blood transfusion did not reveal statistical association even though there were differences in positivity across the risk factors. Key words: Seroprevalence, Hepatitis C virus, Blood Banks, Kano.