Virus Survival Research Articles

Correlation of HPV-16, HPV-18 Genotypes with p16 Expression in Head and Neck Cancer: A Study from Western India

Objectives This retrospective study aims to elucidate the clinical associations of HPV-16, HPV-18, and p16 expression with clinicopathological parameters, risk behaviors, and survival outcomes in head and neck cancer patients from the western Indian population. Methods Clinical data of total 92 enrolled HNC patients diagnosed between years 2021 and 2023 were retrospectively collected from medical records. Formalin-fixed, paraffin-embedded blocks of all enrolled patients were collected whose p16 expression by immunohistochemistry tests were already performed. HPV-16 and HPV-18 infection was studied by real-time polymerase chain reaction. Associations between viral status, p16 expression, clinicopathological parameters, risk behaviors, and survival outcomes were assessed using SPSS statistical software version 20. p-Value ≤0.05 was considered to be statistically significant. Results Among the 92 enrolled HNC patients, HPV-16 infection was detected in only 12 (13%) patients, with the remaining 80 (87%) testing negative. No HPV-18 infections were observed in any patient. Additionally, p16 expression was positive in only 13 (14%) patients, while 79 (86%) showed negative expression. A statistically significant correlation was found between metastasis involvement and positive HPV-16 infection (p < 0.001), with all HPV-16-positive cases exhibiting metastasis. A trend was also noted between the base of tongue and other clinical site subtypes with positive HPV-16 infection (p = 0.063). However, no other clinicopathological or risk behaviors showed significant associations with HPV-16 infection and p16 expression. Overall survival analysis revealed that neither HPV-16 infection nor p16 expression served as significant prognosticators in the HNC patient cohort (p > 0.05). Conclusion This study provides comprehensive insights into the clinical relevance of HPV-16, HPV-18 infections, and p16 expression in HNC among the western Indian population. Understanding the associations between HPV-16, HPV-18, and p16 expression with clinicopathological parameters and survival outcomes may aid in optimizing patient management strategies, including personalized treatment approaches and targeted interventions. Further prospective studies are warranted to validate these findings and explore potential therapeutic implications.

Characterization of Collaborative Cross mouse founder strain CAST/EiJ as a novel model for lethal COVID-19

Mutations in SARS-CoV-2 variants of concern (VOCs) have expanded the viral host range beyond primates, and a few other mammals, to mice, affording the opportunity to exploit genetically diverse mouse panels to model the broad spectrum of responses to infection in patient populations. Here we surveyed responses to VOC infection in genetically diverse Collaborative Cross (CC) founder strains. Infection of wild-derived CC founder strains produced a broad range of viral burden, disease susceptibility and survival, whereas most other strains were resistant to disease despite measurable lung viral titers. In particular, CAST/EiJ, a wild-derived strain, developed high lung viral burdens, more severe lung pathology than seen in other CC strains, and a dysregulated cytokine profile resulting in morbidity and mortality. These inbred mouse strains may serve as a valuable platform to evaluate therapeutic countermeasures against severe COVID-19 and other coronavirus pandemics in the future.

Host cytokine genetic polymorphisms in a selected population of persons living with hepatitis B virus infection in the central region of Ghana.

Hepatitis B virus (HBV) infection is a public health concern in resource limited settings like Ghana. Over the past decades, it is noted that the natural course of HBV in persons infected are taking a worse turn leading to liver cirrhosis and cancer. The outcome of HBV infection is influenced by viral and host factors including genetics. Cytokine variations affect virus survival and progression and may even influence associated complications. Cytokines such as tumor necrosis factor alpha (TNF-α), interleukins (IL-4, IL-6, IL-8, IL-10, IL-18), interferon gamma (IFN)-γ, and tumor growth factor-beta (TGF-β) have key roles in HBV infection and modulation. In this study, polymorphisms occurring in five cytokines were analysed to understand how they can influence prognosis of HBV infection. The study is a single centre cross-sectional study involving 227 participants made up of HBV infected participants and HBV-negative controls. Recruitment was from March 2021 to April 2022. Blood samples were taken for full blood count, HBV antigen profile, liver function tests, HBV DNA quantification and cytokine genotyping. FIB score was calculated using available tools. Statistical analysis was undertaken with p < 0.05 set as statistically significant. The 20-39-year-old group formed majority of the HBV infected participants with 60% of all participants being classified as healthy HBsAg carriers. IL2 rs1479920 GG carriers ((1258.93; 0.00-5011.87) IU/mL had reduced HBV DNA in comparison to IL2 rs1479920 AA ((5011.87; 2113.49-5956.62) /AG (3548.13; 0.00-6309.57) IU/mL carriers. TNF-α rs1800629 AA carriers (1258.93; 0.00-3981.07) IU/mL had a reduction in HBV DNA levels in comparison to TNF-α rs1800629 GG carriers (1584.89; 0.00-5011.87) IU/mL. The results of univariate (OR = 0.08, 0.00-0.93; p = 0.043) and multivariate (OR = 0.02, 0.00-0.67; p = 0.029) analysis, showed that carrying TNF-α rs1800629 AA genotype reduce susceptibility to high FIB score compared with GG genotypes. In univariate analysis, subjects aged 20-39years (OR = 5.00, 1.13-6.10; p = 0.034) and 40-59years (OR = 41.99, 3.74-47.21; p = 0.0002) were more susceptible to high FIB score compared to subjects aged 1-19years. Being female (OR = 2.42, 1.03-5.71; p = 0.043) in the univariate models showed higher odds of having high levels of HBV DNA in the multivariate model. There was a reduced likelihood of herbal medicine usage influencing HBV DNA levels significantly (OR = 0.29, 0.10-0.86; p = 0.025). In conclusion, variations in IL2 rs1479920 GG and IL2 rs1479921 AA could offer protective effects by reducing HBV DNA. TNF-α rs179924CT may also cause elevation in HBV DNA levels whiles TNF-α -308A/G, showed a potential protective effect on liver scarring in HBV infected participants. It is therefore important to take a further look at such variations for understanding of HBV modulation in the Ghanaian population.

Efficacy of total laparoscopic hysterectomy without uterine manipulators in patient with early-stage cervical cancer.

To evaluate the feasibility and safety of total laparoscopic hysterectomy (TLH) without uterine manipulator for patients with early-stage cervical cancer. This study was based on retrospective analysis of clinical data of 72 patients with early-stage cervical cancer who received TLH treatment in Meizhou People's Hospital from January 2018 to December 2020. Of them, 40 patients underwent routine TLH (control group), and 32 patients received TLH without lifting the uterus using uterine manipulator (observation group). Changes in tumor marker levels, human papilloma virus (HPV) status, complications, and survival between two groups of patients were compared. There was no significant difference in the incidence of postoperative complications between the two groups (P>0.05). After the surgery, levels of squamous cell carcinoma antigen (SCC-Ag), carcinoembryonic antigen (CEA), and cancer antigen 125 (CA-125) in both groups of patients were significantly reduced compared to before the surgery, and significantly lower in the observation group compared to the control group at one and two years after the surgery (P<0.05). After three years of postoperative follow-up, there was no significant difference in cumulative survival rates between the two groups (P>0.05). Compared with conventional laparoscopy, hysteroscopy without the use of uterine manipulators can significantly reduce the levels of SCC-Ag, CEA, and CA-125 in patients with early-stage cervical cancer within two years after the surgery, without increasing postoperative complications or affecting survival, and has the same safety.

Mpox Keratitis: A Case Report and Review.

Mpox is a rare infectious disease. Lack of knowledge among eye care professionals regarding mpox keratitis greatly reduces the likelihood of diagnosis and effective management. This report and review seek to increase the knowledge of mpox keratitis among eye care professionals. We report a patient with mpox keratitis who underwent successful penetrating keratoplasty, with 20 years of follow-up. A systematic literature search and review of cases of mpox keratitis from 1970 to 2024 was performed. A total of 24 articles and 2 abstracts reporting 35 cases of mpox keratitis were identified. A frequency of 0.5% to 1.0% may be the lower range of mpox keratitis among symptomatic patients with a confirmed mpox diagnosis. Mpox keratitis occurred with and without systemic mpox. Initial misdiagnoses were common (40%). Polymerase chain reaction results aided clinical diagnosis. Corneal disease ranged from mild epitheliopathy to fulminant ulcerative keratitis. Outcomes ranged from 20/20 acuity to no light perception. In the absence of fulminant systemic disease, tecovirimat was associated with clinical improvement of mpox keratitis in almost all cases. Our case is the only known report of successful penetrating keratoplasty for mpox keratitis and the only case whereby monkeypox virus was cultured from the corneal surface. Mpox keratitis is rare but can result in severe vision loss and blindness. Systemic tecovirimat seems to be effective in treating mpox keratitis, although the low frequency of keratitis precludes clinical trials. Topical steroids may extend virus survival in the cornea. Polymerase chain reaction may help confirm mpox corneal involvement.

Subgenomic flaviviral RNAs and human proteins: in silico exploration of anti-host defense mechanisms

Flaviviruses pose significant global health threats, infecting over 300 million people annually. Among their evasion strategies, the production of subgenomic flaviviral RNAs (sfRNAs) from the 3′ UTR of viral genomes is particularly notable. Utilizing a comprehensive in silico approach with the catRAPID algorithm, we analyzed over 300,000 interactions between sfRNAs and human proteins derived from more than 8000 flavivirus genomes, including Dengue, Zika, Yellow Fever, West Nile, and Japanese Encephalitis viruses. By providing the first extensive atlas of sfRNA interactions, we offer new insights into how flaviviruses can manipulate host cellular machinery to facilitate viral survival and persistence. Our study not only validated known interactions but also revealed novel human proteins that could be involved in sfRNA-mediated host defense evasion, including helicases, splicing factors, and chemokines. These findings significantly expand the known interactome of sfRNAs with human proteins, underscoring their role in modulating host cellular pathways. Intriguingly, we predict interaction with stress granules, a critical component of the cellular response to viral infection, suggesting a mechanism by which flaviviruses inhibit their formation to evade host defenses. Moreover, a set of highly-interacting proteins in common among the sfRNAs showed predictive power to identify sfRNA-forming regions, highlighting how protein signatures could be used to annotate viruses. This atlas not only serves as a resource for exploring therapeutic targets but also aids in the identification of sfRNA biomarkers for improved flavivirus diagnostics.

SARS-CoV-2 infection and transmission via the skin to oro-nasal route with the production of bioaerosols in the ferret model.

Direct and indirect transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been attributed to virus survival in droplets, bioaerosols and on fomites including skin and surfaces. Survival of SARS-CoV-2 variants of concern (Alpha, Beta, Gamma, and Delta) on the skin and virus transference following rounds of skin-to-skin contact were assessed on porcine skin as a surrogate for human skin. SARS-CoV-2 variants were detectable on skin by RT-qPCR after 72 h at biologically relevant temperatures (35.2 °C) with viral RNA (vRNA) detected after ten successive skin-to-skin contacts. Skin-to-skin virus transmission to establish infection in ferrets as a model for mild/asymptomatic SARS-CoV-2 infection in mustelids and humans was also investigated and compared to intranasal ferret inoculation. Naïve ferrets exposed to Delta variant SARS-CoV-2 in a 'wet' or 'dry' form on porcine skin resulted in robust infection with shedding detectable for up to 14 days post-exposure, at comparable viral loads to ferrets inoculated intranasally. Transmission of SARS-CoV-2 to naïve ferrets in direct contact with infected ferrets was achieved, with environmental contamination detected from ferret fur swabs and air samples. Genetic substitutions were identified in bioaerosol samples acquired following single contact passage in ferrets, including Spike, ORF1ab, and ORF3a protein sequences, suggesting a utility for monitoring host adaptation and virus evolution via air sampling. The longevity of SARS-CoV-2 variants survival directly on the skin and skin-to-skin transference, enabling subsequent infection via the skin to oro-nasal contact route, could represent a pathway for SARS-CoV-2 infection with implications to public and veterinary health.

Engineering stress as a motivation for filamentous virus morphology

Many viruses are pleomorphic in shape and size, with pleomorphism often thought to correlate with infectivity, pathogenicity, or virus survival. For example, influenza and respiratory syncytial virus particles range in size from small spherical virions to filaments reaching many micrometers in length. We have used a pressure vessel model to investigate how the length and width of spherical and filamentous virions can vary for a given critical stress and fluorescence super-resolution microscopy along with image analysis tools to fit imaged influenza viruses to the model. We have shown that influenza virion dimensions fit within the theoretical limits of the model, suggesting that filament formation may be a way to increase an individual virus’s volume without particle rupture. We have also used cryoelectron microscopy to investigate influenza and respiratory syncytial virus dimensions at the extrema of the model and used the pressure vessel model to explain the lack of alternative virus particle geometries. Our approach offers insight into the possible purpose of filamentous virus morphology and is applicable to a wide range of other biological entities, including bacteria and fungi.

HSV-2 Manipulates Autophagy through Interferon Pathway: A Strategy for Viral Survival.

Autophagy, an evolutionarily conserved cellular process, influences the regulation of viral infections. While the existing understanding indicates that Herpes Simplex Virus type 2 (HSV-2) maintains a basal level of autophagy to support its viral yield, the precise pathways governing the induction of autophagy during HSV-2 infection remain unknown. Therefore, this study aims to explore the role of type I interferons (IFN-I) in modulating autophagy during HSV-2 infection and to decode the associated signaling pathways. Our findings revealed an interplay wherein IFN-I regulates the autophagic response during HSV-2 infection. Additionally, we investigated the cellular pathways modulated during this complex process. Exploring the intricate network of signaling events involved in autophagy induction during HSV-2 infection holds promising therapeutic implications. Identifying these pathways advances our understanding of host-virus interactions and holds the foundation for developing targeted therapeutic strategies against HSV-2. The insight gained from this study provides a platform for exploring potential therapeutic targets to restrict HSV-2 infections, addressing a crucial need in antiviral research.

The inoculum dose of Zika virus can affect the viral replication dynamics, cytokine responses and survival rate in immunocompromised AG129 mice

Zika virus, a mosquito-borne arbovirus, has repeatedly caused large pandemics with symptoms worsening from mild and self-limiting diseases to Guillain–Barré syndrome in adults and fetal microcephaly in newborns. In recent years, Zika virus diseases have posed a serious threat to human health. The shortage of susceptible small animal models makes it difficult to study pathogenic mechanisms and evaluate potential therapies for Zika virus infection. Therefore, we chose immunocompromised mice (AG129 mice) deficient in IFN-α/β and IFN-γ receptors, which can abolish the innate immune system that prevents Zika virus infection early. AG129 mice were infected with the Zika virus, and this mouse model exhibited replication dynamics, tissue tropism, pathological lesion and immune activation of the Zika virus. Our results suggest that the inoculum dose of Zika virus can affect the viral replication dynamics, cytokine responses and survival rate in AG129 mice. By testing the potential antiviral drug favipiravir, several critical indicators, including replication dynamics and survival rates, were identified in AG129 mice after Zika virus infection. It is suggested that the model is reliable for drug evaluation. In brief, this model provides a potential platform for studies of the infectivity, virulence, and pathogenesis of the Zika virus. Moreover, the development of an accessible mouse model of Zika virus infection will expedite the research and deployment of therapeutics and vaccines.

Alcohol does not impact chronic hepatitis C treatment outcomes but increases risk for progressive liver disease: Findings from a prospective multicentre Australian study (OPERA-C).

Alcohol use is common in patients with chronic hepatitis C virus (HCV) infection. We examined the impact of alcohol use on direct-acting antiviral (DAA) therapy outcome and the clinical course of liver disease and 2-year survival for patients receiving HCV DAA therapy. Adults (n = 2624) recruited from 26 Australian hospital liver clinics during 2016-2021 were followed up for 2 years. Risky alcohol use was defined by a combination of self-report (≥40 g/day of ethanol), physician-reported history of problematic alcohol use, and anti-craving medication prescription via population-based database linkage. We examined factors associated with advanced liver fibrosis and survival using multivariable logistic and Cox regression. Among 1634 patients (62.3%) with risky alcohol use, 24.6% reported consuming ≥40 g/day of alcohol, 98.3% physician-reported problematic alcohol use; only 4.1% were dispensed naltrexone/acamprosate. One hundred and forty-three patients with cirrhosis reported ≥40 g/day of alcohol, 6 (4.3%) were prescribed naltrexone/acamprosate. Risky alcohol use was associated with advanced fibrosis (adjusted-odds ratio 1.69, 95% confidence interval 1.32-2.17) and patients were over-represented for cirrhosis (45.1% vs. 25.6% in no-risky alcohol use [p < 0.001]) and hepatocellular carcinoma (5.7% vs. 2.5% [p < 0.001]). Sustained viral response (p = 0.319) and 2-year survival (adjusted-hazard ratio 1.98, 95% confidence interval 0.84-4.63) after DAA therapy were not associated with risky alcohol use. Risky alcohol use in HCV patients was prevalent, but did not reduce HCV cure. Treatment for alcohol dependence was low. Risky alcohol use may be under-recognised in liver clinics. Better integration of addiction medicine into liver services and increased resourcing and addiction medicine training opportunities for hepatologists may help address this.

Psychosocial Factors Linked to Uncontrolled Infection and Mortality among People Living with HIV Who Use Substances: A Latent Class Analysis

To determine whether endorsement patterns of psychosocial symptoms revealed distinct subgroups, or latent classes, of people living with HIV who use substances (PLWH-SU), and to assess whether these classes demonstrated differential health outcomes over time. This study uses data from 801 PLWH-SU initially enrolled across 11 US hospitals during 2012–2014 and followed up in 2017. Latent class analysis included 28 psychosocial items. Regression analysis examined class membership as a predictor of viral suppression. Survival analysis examined class as a predictor of all-cause mortality. The selected model identified five unique classes. Individuals in classes characterized by more severe and more numerous psychosocial symptoms at baseline had lower likelihoods of viral suppression and survival. The study demonstrated the importance of considering patterns of overlapping psychosocial symptoms to identify subgroups of PLWH-SU and reveal their risks for adverse outcomes. Integration of primary, mental health, and substance use care is essential to address the needs of this population.

Data analysis evidence beyond correlation of a possible causal impact of weather on the COVID-19 spread, mediated by human mobility

Previous correlative and modeling approaches indicate influences of environmental factors on COVID-19 spread through atmospheric conditions’ impact on virus survival and transmission or host susceptibility. However, causal connections from environmental factors to the pandemic, mediated by human mobility, received less attention. We use the technique of Convergent Cross Mapping to identify the causal connections, beyond correlation at the country level, between pairs of variables associated with weather conditions, human mobility, and the number of COVID-19 cases for 32 European states. Here, we present data-based evidence that the relatively reduced number of cases registered in Northern Europe is related to the causal impact of precipitation on people’s decision to spend more time at home and that the relatively large number of cases observed in Southern Europe is linked to people’s choice to spend time outdoors during warm days. We also emphasize the channels of the significant impact of the pandemic on human mobility. The weather-human mobility connections inferred here are relevant not only for COVID-19 spread but also for any other virus transmitted through human interactions. These results may help authorities and public health experts contain possible future waves of the COVID-19 pandemic or limit the threats of similar human-to-human transmitted viruses.

Characterization of Collaborative Cross mouse founder strain CAST/EiJ as a novel model for lethal COVID-19.

Mutations in SARS-CoV-2 variants of concern (VOCs) have expanded the viral host range beyond primates, and a limited range of other mammals, to mice, affording the opportunity to exploit genetically diverse mouse panels to model the broad range of responses to infection in patient populations. Here we surveyed responses to VOC infection in genetically diverse Collaborative Cross (CC) founder strains. Infection of wild-derived CC founder strains produced a broad range of viral burden, disease susceptibility and survival, whereas most other strains were resistant to disease despite measurable lung viral titers. In particular, CAST/EiJ, a wild-derived strain, developed high lung viral burdens, more severe lung pathology than seen in other CC strains, and a dysregulated cytokine profile resulting in morbidity and mortality. These inbred mouse strains may serve as a valuable platform to evaluate therapeutic countermeasures against severe COVID-19 and other coronavirus pandemics in the future.

The direct and indirect drivers shaping RNA viral communities in grassland soils.

Climate change has been reshaping the soil environment as well as the residing microbiome. This study provides field-relevant information on how environmental and community factors collectively shape soil RNA communities and contribute to ecological understanding of RNA viral survival under various environmental conditions and virus-host interactions in soil. This knowledge is critical for predicting the viral responses to climate change and the potential emergence of biothreats.

A Comparative Experimental and Computational Study on the Nature of the Pangolin-CoV and COVID-19 Omicron.

The relationship between pangolin-CoV and SARS-CoV-2 has been a subject of debate. Further evidence of a special relationship between the two viruses can be found by the fact that all known COVID-19 viruses have an abnormally hard outer shell (low M disorder, i.e., low content of intrinsically disordered residues in the membrane (M) protein) that so far has been found in CoVs associated with burrowing animals, such as rabbits and pangolins, in which transmission involves virus remaining in buried feces for a long time. While a hard outer shell is necessary for viral survival, a harder inner shell could also help. For this reason, the N disorder range of pangolin-CoVs, not bat-CoVs, more closely matches that of SARS-CoV-2, especially when Omicron is included. The low N disorder (i.e., low content of intrinsically disordered residues in the nucleocapsid (N) protein), first observed in pangolin-CoV-2017 and later in Omicron, is associated with attenuation according to the Shell-Disorder Model. Our experimental study revealed that pangolin-CoV-2017 and SARS-CoV-2 Omicron (XBB.1.16 subvariant) show similar attenuations with respect to viral growth and plaque formation. Subtle differences have been observed that are consistent with disorder-centric computational analysis.

Host cells reprogram lipid droplet synthesis through YY1 to resist PRRSV infection.

Metabolism in host cells can be modulated after viral infection, favoring viral survival or clearance. Here, we report that lipid droplet (LD) synthesis in host cells can be modulated by yin yang 1 (YY1) after porcine reproductive and respiratory syndrome virus (PRRSV) infection, resulting in active antiviral activity. As a ubiquitously distributed transcription factor, there was increased expression of YY1 upon PRRSV infection both in vitro and in vivo. YY1 silencing promoted the replication of PRRSV, whereas YY1 overexpression inhibited PRRSV replication. PRRSV infection led to a marked increase in LDs, while YY1 knockout inhibited LD synthesis, and YY1 overexpression enhanced LD accumulation, indicating that YY1 reprograms PRRSV infection-induced intracellular LD synthesis. We also showed that the viral components do not colocalize with LDs during PRRSV infection, and the effect of exogenously induced LD synthesis on PRRSV replication is nearly lethal. Moreover, we demonstrated that YY1 affects the synthesis of LDs by regulating the expression of lipid metabolism genes. YY1 negatively regulates the expression of fatty acid synthase (FASN) to weaken the fatty acid synthesis pathway and positively regulates the expression of peroxisome proliferator-activated receptor gamma (PPARγ) to promote the synthesis of LDs, thus inhibiting PRRSV replication. These novel findings indicate that YY1 plays a crucial role in regulating PRRSV replication by reprogramming LD synthesis. Therefore, our study provides a novel mechanism of host resistance to PRRSV and suggests potential new antiviral strategies against PRRSV infection.IMPORTANCEPorcine reproductive and respiratory virus (PRRSV) has caused incalculable economic damage to the global pig industry since it was first discovered in the 1980s. However, conventional vaccines do not provide satisfactory protection. It is well known that viruses are parasitic pathogens, and the completion of their replication life cycle is highly dependent on host cells. A better understanding of host resistance to PRRSV infection is essential for developing safe and effective strategies to control PRRSV. Here, we report a crucial host antiviral molecule, yin yang 1 (YY1), which is induced to be expressed upon PRRSV infection and subsequently inhibits virus replication by reprogramming lipid droplet (LD) synthesis through transcriptional regulation. Our work provides a novel antiviral mechanism against PRRSV infection and suggests that targeting YY1 could be a new strategy for controlling PRRSV.

Arthropod-Borne Viruses of Human and Animal Importance: Overwintering in Temperate Regions of Europe during an Era of Climate Change.

The past three decades have seen an increasing number of emerging arthropod-borne viruses in temperate regions This process is ongoing, driven by human activities such as inter-continental travel, combined with the parallel emergence of invasive arthropods and an underlying change in climate that can increase the risk of virus transmission and persistence. In addition, natural events such as bird migration can introduce viruses to new regions. Despite the apparent regularity of virus emergence, arthropod-borne viruses circulating in temperate regions face the challenge of the late autumn and winter months where the arthropod vector is inactive. Viruses therefore need mechanisms to overwinter or they will fail to establish in temperate zones. Prolonged survival of arthropod-borne viruses within the environment, outside of both vertebrate host and arthropod vector, is not thought to occur and therefore is unlikely to contribute to overwintering in temperate zones. One potential mechanism is continued infection of a vertebrate host. However, infection is generally acute, with the host either dying or producing an effective immune response that rapidly clears the virus. There are few exceptions to this, although prolonged infection associated with orbiviruses such as bluetongue virus occurs in certain mammals, and viraemic vertebrate hosts therefore can, in certain circumstances, provide a route for long-term viral persistence in the absence of active vectors. Alternatively, a virus can persist in the arthropod vector as a mechanism for overwintering. However, this is entirely dependent on the ecology of the vector itself and can be influenced by changes in the climate during the winter months. This review considers the mechanisms for virus overwintering in several key arthropod vectors in temperate areas. We also consider how this will be influenced in a warming climate.

Hepatitis C Virus and Molecular Mimicry.

This review delves into the interactions between hepatitis C virus (HCV) and the host immune system, shedding light on how by using the mechanism of molecular mimicry, the virus strategically evades the immune system, resulting in a cascade of diverse complications. HCV, notorious for its ability to persistently infect hepatocytes, employs molecular mimicry to resemble host proteins, thereby avoiding immune detection and mounting an effective defense. This mimicry also triggers systemic autoimmune responses that lead to various sequelae. The objective of this review is to comprehensively explore the role of HCV-induced molecular mimicry, which not only facilitates viral survival but is also instrumental in developing autoimmune and inflammatory disorders. By mimicking host proteins, HCV triggers an immune response that inadvertently attacks the host, fostering the development of autoimmune and other inflammatory disorders. Understanding the nuanced mechanisms of HCV-mediated molecular mimicry provides crucial insights into the multifaceted sequelae of viral infections on host immune responses. Unravelling these complexities is paramount for advancing therapeutic strategies that not only target the virus directly but also mitigate the secondary autoimmune and inflammatory complications induced by HCV.

ON THE VECTOR PROPERTIES OF HENOSEPILACHNA VIGINTIOCTOMACULATA MOTSCHULSKY, 1858 (COLEOPTERA: COCCINELLIDAE) IN THE TRANSMISSION OF POTATO VIRUSES

The survival, transmission, and spread of most viruses depend on insect vectors. The potato ladybird Henosepilachna vigintioctomaculata transfers such potato viruses as PVY, PVM, PVX, PVS, PLRV, and PSTVd from diseased potato plants to healthy ones. The plant viruses were detected in all plants by the end of the experiment. The studied potato ladybird beetles had different orientation behavior while searching for food depending on whether they were infected with PVY, PVM, PVX, PVS, PLRV, and PSTVd or not. The infected H. vigintioctomaculata fed predominantly on healthy plants (72% of the beetles).