Vaccination Model and Optimal Control Analysis of Novel Corona Virus Transmission Dynamics

In this paper, the mathematical model of the coronavirus pandemic with vaccination is formulated and analyzed to show the impact of severe acute respiratory syndrome coronavirus 2 pathogens in the environmental reservoir. In the model analysis, the vaccination-induced reproduction number which helps us in establishing the local and global stability of COVID-19-free and endemic equilibrium points was derived. The local stability of the COVID-19-free equilibrium is established via the Jacobian matrix and Routh-Hurwitz criteria. In contrast, the global stability of the endemic equilibrium is proved by using an appropriate Lyapunov function. Sensitivity indices are also discussed. The proposed model is extended into the optimal control problem by incorporating three control variables: preventive, medical care, and surface disinfection. Then, the necessary conditions for the optimal control of the disease were analyzed by applying Pontryagin minimum principle. Finally, the numerical simulations indicated that a combination of medical care and surface disinfection strategies is effective in controlling the disease epidemic. [ FROM AUTHOR] Copyright of Journal of Mathematical Sciences is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

A Computational Approach for the Characterization of Airborne Pathogen Transmission in Turbulent Molecular Communication Channels

Airborne pathogen transmission mechanisms play a key role in the spread of infectious diseases such as COVID-19. In this work, we propose a computational fluid dynamics (CFD) approach to model and statistically characterize airborne pathogen transmission via pathogen-laden particles in turbulent channels from a molecular communication viewpoint. To this end, turbulent flows induced by coughing and the turbulent dispersion of droplets and aerosols are modeled by using the Reynolds-averaged Navier-Stokes equations coupled with the realizable k-model and the discrete random walk model, respectively. Via simulations realized by a CFD simulator, statistical data for the number of received particles are obtained. These data are post-processed to obtain the statistical characterization of the turbulent effect in the reception and to derive the probability of infection. Our results reveal that the turbulence has an irregular effect on the probability of infection, which shows itself by the multi-modal distribution as a weighted sum of normal and Weibull distributions. Furthermore, it is shown that the turbulent MC channel is characterized via multi-modal, i.e., sum of weighted normal distributions, or stable distributions, depending on the air velocity. Crown

Existential insecurity and deference to authority: the pandemic as a natural experiment

IntroductionThe global coronavirus pandemic offers a quasi-experimental setting for understanding the impact of sudden exposure to heightened existential risk upon both individual and societal values. MethodsWe examined the effect of the pandemic on political attitudes by comparing data from eight countries surveyed before and after the worldwide spread of COVID-19 in March 2020 with continuous weekly polling tracker data from the United Kingdom from 2019 to 2021. Multilevel models were used to explore the drivers of change, and the results indicated that reported emotions of fear and stress were positively associated with institutional approval during periods of greater pathogen risk. ResultsOur findings revealed that support for political and technocratic authority, as well as satisfaction with political institutions, rose significantly above long-term historical baselines during the pandemic. DiscussionThe results support the hypothesis that exposure to existential risk results in greater support for authority and that individual feelings of insecurity may be linked to less critical citizen orientations.

Les expériences de gain-de-fonction des virus pathogènes émergents1

Résumé Dans la nature, des virus adaptés à la transmission circulent dans les espèces animales (chauves-souris, oiseaux, rongeurs, primates, etc.). Le franchissement de la barrière des espèces peut se faire par contamination d'autres espèces animales, dont l'homme. Des manipulations génétiques ont été réalisées sur des virus sauvages pour faciliter le passage interespèces et augmenter la virulence virale. Le but était d'identifier les gènes critiques pour la pathogénicité. Ces manipulations ont été réalisées sur des agents pathogènes potentiellement épidémiques, comme Myxovirus influenzae de la grippe aviaire et les coronavirus des épidémies de SRAS et de MERS. Ces expériences dangereuses ont fait l'objet d'un moratoire aux États-Unis (2014-2017). Trois ans après l'émergence du Covid-19, l'origine du SARS-CoV2 d'emblée très contagieux reste un mystère. Il existe deux scénarios pour expliquer son émergence. Les partisans de l'origine naturelle avancent que le virus de la chauve-souris aurait pu infecter directement l'homme, se propageant silencieusement à un faible niveau chez l'homme pendant des années, sans éliminer l'existence d'hôtes intermédiaires non détectés. Cela n'explique pas l'origine à Wuhan, loin des réservoirs naturels de virus. Le site furin serait apparu spontanément à partir d'autres coronavirus. Le scénario alternatif est celui d'un accident de laboratoire à Wuhan, après des expériences de gain-de-fonction à partir d'un SARS-like CoV, voire même la survenue d'une contamination humaine par un virus CoV sauvage recuilli sur le terrain, lors de cultures cellulaires ou des tests sur les animaux à Wuhan. Summary In nature, viruses are well-adapted to transmission in wild animal species (bats, birds, rodents, primates...). The crossing of the species barrier can be done by contamination of other animal species, including humans. Genetic manipulations have been carried out on wild viruses to facilitate interspecies passage and increase viral virulence. The aim was to identify genes critical for pathogenicity. These manipulations have been performed on potentially epidemic pathogens, such as Myxovirus influenzae from avian influenza and coronaviruses from the SARS and MERS epidemics. These dangerous experiments were placed under a moratorium in the United States (2014-2017). Three years after the emergence of Covid-19, the origin of the highly contagious SARS-CoV2 remains a mystery. There are two scenarios to explain its emergence. Proponents of the natural origin argue that the bat virus could have directly infected humans, spreading silently at a low level in humans for years, without eliminating the possibility of undetected intermediate hosts. The furin site would have appeared spontaneously from other coronaviruses. However, this does not explain the specific origin in Wuhan, far from natural virus reservoirs. The alternative scenario is that of a laboratory accident in Wuhan, after gain-of-function experiments with an SARS-like CoV, or even the occurrence of human contamination by a wild CoV virus collected in the field, during cell cultures or animal tests in Wuhan.

A Simple, Pipette-free, and Power-free Device for Virus Nucleic Acid Detection

A portable, inexpensive, and easy-to-manufacture microfluidic device is developed for the detection of SARS-CoV-2 dsDNA fragments. In this device, four reaction chambers separated by carbon fiber rods are pre-loaded with isothermal amplification and CRISPR-Cas12a reagents. The reaction is carried out by simply pulling the rods, without the need for manual pipetting. To facilitate power-free pathogen detection, the entire detection is designed to be heated with a disposable hand warmer. After the CRISPR reaction, the fluorescence signal generated by positive samples is identified by naked eye, using an inexpensive flashlight. This simple and sensitive device will serve as a new model for the next-generation viral diagnostics in either hospital or resource-limited settings. © 2023 SPIE.

Immunotherapy: FAMILIAL CD45RA DEPLETED T CELLS TO TREAT SEVERE REFRACTORY INFECTIONS IN IMMUNOCOMPROMISED PATIENTS

Background & Aim: Immunocompromised patients are susceptible to high-risk opportunistic infections and malignant diseases. If available, most antiviral and antifungal drugs are quite toxic, relatively ineffective, and induce resistance in the long term. Methods, Results & Conclusion(s): We have previously demonstrated the safety of adoptive cell therapy for COVID-19 patients with CD45RA negative cells containing SARS-CoV-2-specific T cells from a donor, chosen based on HLA compatibility and cellular response to SARS-CoV-2 peptide pools. After finishing a Phase 2 randomized multicenter clinical trial (RELEASE, NCT04578210), we concluded that the infusion is safe, effective, accelerates lymphocyte recovery and shows hallmarks of an immune response. To use adoptive cell therapy to treat COVID-19 it would be necessary to develop a biobank of living drugs. For that, we examined the immune evolution performing a longitudinal analysis from previously SARS-CoV-2 infected and infection- naive individuals covering 21 months from infection. Cellular responses were maintained over time while humoral responses increased after vaccination but were gradually lost. Therefore, the best donors would be recovered individuals and two months after vaccination. We also evaluated the effect of dexamethasone (current standard of care treatment for COVID-19 and other infections involving lymphopenia) and Interleukin-15 (cytokine involved in T-cell maintenance and survival) on CD45RA negative. Dexamethasone did not alter cell functionality, proliferation or phenotype at a clinical-practice concentration, while interleukin-15 increased the memory T-cell and T-regulatory cell activation state, and interferon gamma release. Furthermore, we applied the adoptive passive transfer of CD45RA negative cells containing pathogen-specific memory T-cells to other infectious diseases characterized by sustained lymphopenia. We infused six immunocompromised patients with Cytomegalovirus, BK virus, Aspergillus, and Epstein-Barr virus lymphoproliferative disease. Patients experienced pathogen clearance, resolution of symptoms and lymphocyte increase. Transient microchimerism was detected in three patients. The use of CD45RA negative cells containing specific memory T cells of a third-party donor for treating severe pathogenic diseases in immunocompromised patients is feasible, safe, and effective, and has an advantage over other cell therapies such as lower costs and a less complex regulatory environment.Copyright © 2023 International Society for Cell & Gene Therapy

Taking hospital pathogen surveillance to the next level.

High-throughput bacterial genomic sequencing and subsequent analyses can produce large volumes of high-quality data rapidly. Advances in sequencing technology, with commensurate developments in bioinformatics, have increased the speed and efficiency with which it is possible to apply genomics to outbreak analysis and broader public health surveillance. This approach has been focused on targeted pathogenic taxa, such as Mycobacteria, and diseases corresponding to different modes of transmission, including food-and-water-borne diseases (FWDs) and sexually transmitted infections (STIs). In addition, major healthcare-associated pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and carbapenemase-producing Klebsiella pneumoniae are the focus of research projects and initiatives to understand transmission dynamics and temporal trends on both local and global scales. Here, we discuss current and future public health priorities relating to genome-based surveillance of major healthcare-associated pathogens. We highlight the specific challenges for the surveillance of healthcare-associated infections (HAIs), and how recent technical advances might be deployed most effectively to mitigate the increasing public health burden they cause.

The Pivotal Role of Galectin-3 in Viral Infection: A Multifaceted Player in Host-Pathogen Interactions.

Galectin-3 (Gal-3), a beta-galactoside-binding lectin, plays a pivotal role in various cellular processes, including immune responses, inflammation, and cancer progression. This comprehensive review aims to elucidate the multifaceted functions of Gal-3, starting with its crucial involvement in viral entry through facilitating viral attachment and catalyzing internalization. Furthermore, Gal-3 assumes significant roles in modulating immune responses, encompassing the activation and recruitment of immune cells, regulation of immune signaling pathways, and orchestration of cellular processes such as apoptosis and autophagy. The impact of Gal-3 extends to the viral life cycle, encompassing critical phases such as replication, assembly, and release. Notably, Gal-3 also contributes to viral pathogenesis, demonstrating involvement in tissue damage, inflammation, and viral persistence and latency elements. A detailed examination of specific viral diseases, including SARS-CoV-2, HIV, and influenza A, underscores the intricate role of Gal-3 in modulating immune responses and facilitating viral adherence and entry. Moreover, the potential of Gal-3 as a biomarker for disease severity, particularly in COVID-19, is considered. Gaining further insight into the mechanisms and roles of Gal-3 in these infections could pave the way for the development of innovative treatment and prevention options for a wide range of viral diseases.

Pathogen genomics in public health laboratories: successes, challenges, and lessons learned from California's SARS-CoV-2 Whole-Genome Sequencing Initiative, California COVIDNet.

The capacity for pathogen genomics in public health expanded rapidly during the coronavirus disease 2019 (COVID-19) pandemic, but many public health laboratories did not have the infrastructure in place to handle the vast amount of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequence data generated. The California Department of Public Health, in partnership with Theiagen Genomics, was an early adopter of cloud-based resources for bioinformatics and genomic epidemiology, resulting in the creation of a SARS-CoV-2 genomic surveillance system that combined the efforts of more than 40 sequencing laboratories across government, academia and industry to form California COVIDNet, California's SARS-CoV-2 Whole-Genome Sequencing Initiative. Open-source bioinformatics workflows, ongoing training sessions for the public health workforce, and automated data transfer to visualization tools all contributed to the success of California COVIDNet. While challenges remain for public health genomic surveillance worldwide, California COVIDNet serves as a framework for a scaled and successful bioinformatics infrastructure that has expanded beyond SARS-CoV-2 to other pathogens of public health importance.

The effectiveness of disinfection protocols in medical school osteopathic manipulative medicine labs.

CONTEXT: In light of the COVID-19 pandemic, healthcare-associated infections have taken center stage. Healthcare has adjusted workflows to accommodate for more robust disinfecting regiments to help protect the community. This has resulted in the need for medical institutions to reevaluate the current disinfection protocols down to the student level. The osteopathic manipulative medicine (OMM) laboratory provides an optimal avenue for assessing the effectiveness of medical students' ability to clean examination tables. With OMM laboratories having a high level of interaction, adequate disinfection is important for the health and safety of students and teaching faculties. OBJECTIVES: This study will evaluate the effectiveness of the current disinfection protocols in the medical school OMM labs. METHODS: A cross-sectional, nonrandomized study was performed on 20 OMM examination tables utilized for osteopathic training. Tables were chosen based on their close proximity to the podium. Close proximity was utilized as a criteria to increase the probability of utilization by students. The sampled tables were observed to ensure their use by students during class. Initial samples were collected in the morning after disinfection by Environmental Services. Terminal samples were collected after Osteopathic medical students utilized and disinfected the OMM examination tables. Samples were collected from the face-cradle and midtorso regions and analyzed utilizing adenosine triphosphate (ATP) bioluminescence assays with an AccuPoint Advanced HC Reader. This reader provides a digital readout of the quantity of light measured in relative light units (RLUs), which is directly correlated to the amount of ATP present in the sample, providing an estimated pathogen count. For statistical analysis, a Wilcoxon signed-rank test was utilized to find statistical differences in RLUs in samples after initial and terminal disinfection. RESULTS: The face cradle showed a 40 % increase in failure rate in samples after terminal disinfection when samples were compared after initial disinfection. A Wilcoxon signed-rank test revealed an estimated pathogen level for face cradle that was significantly higher after terminal disinfection (median, 4,295 RLUs; range, 2,269-12919 RLUs; n=20) compared to initial disinfection (median, 769 RLUs; range, 29-2,422 RLUs; n=20), z=-3.8, p=0.00008, with a large effect size, d=2.2. The midtorso region showed a 75 % increase in samples after terminal disinfection when samples were compared after initial disinfection. A Wilcoxon signed-rank test revealed that the estimated pathogen levels for midtorso were significantly higher after terminal disinfecting (median, 656 RLUs; range, 112-1,922 RLUs; n=20) compared to initial disinfecting (median, 128 RLUs; range, 1-335 RLUs; n=20), z=-3.9, p=0.00012, with a large effect size, d=1.8. CONCLUSIONS: This study suggests that medical students frequently failed to disinfect high-touch regions on examination tables, such as the midtorso and the face cradle. It is recommended that the current OMM lab disinfection protocol be modified to include the disinfection of high-touch regions in order to reduce the possibility of pathogen transmission. Further research should explore the effectiveness of disinfection protocols in clinical settings such as outpatient offices.

The impact of pandemic mental cognition on cultural values: an empirical study based on social media.

BACKGROUND: COVID-19 has triggered a global public health crisis, and had an impact on economies, societies, and politics around the world. Based on the pathogen prevalence hypothesis suggested that residents of areas with higher infection rates are more likely to be collectivists as compared with those of areas with lower infection rates. Many researchers had studied the direct link between infectious diseases and individualism/collectivism (infectious diseases→ cultural values), but no one has focused on the specific psychological factors between them: (infectious diseases→ cognition of the pandemic→ cultural values). To test and develop the pathogen prevalence hypothesis, we introduced pandemic mental cognition and conducted an empirical study on social media (Chinese Sina Weibo), hoping to explore the psychological reasons behind in cultural value changes in the context of a pandemic. METHODS: We downloaded all posts from active Sina Weibo users in Dalian during the pandemic period (January 2020 to May 2022) and used dictionary-based approaches to calculate frequency of words from two domains (pandemic mental cognition and collectivism/individualism), respectively. Then we used the multiple log-linear regression analysis method to establish the relationship between pandemic mental cognition and collectivism/individualism. RESULTS: Among three dimensions of pandemic mental cognition, only the sense of uncertainty had a significant positive relationship with collectivism, and also had a marginal significant positive relationship with individualism. There was a significant positive correlation between the first-order lag term AR(1) and individualism, which means the individualism tendency was mainly affected by its previous level. CONCLUSIONS: The study found that more collectivist regions are associated with a higher pathogen burden, and recognized the sense of uncertainty as its underlying cause. Results of this study validated and further developed the pathogen stress hypothesis in the context of the COVID-19 pandemic.

Clinical influence of multiplex polymerase chain reaction routine uses in urgent pediatric admissions.

BACKGROUND: The coronavirus disease 2019 outbreak has prompted some hospitals to implement screening tests upon admission since 2020. FilmArray® Respiratory 2.1 Panel (FilmArray) is a multiplex polymerase chain reaction (PCR) test with high sensitivity and specificity for detecting respiratory pathogens. We aimed to assess the clinical influence of the routine use of FilmArray for pediatric patients, including those without symptoms suggestive of an infection. METHODS: We conducted a single-center retrospective observational study, which investigated patients aged ≤15 years who underwent FilmArray on admission in 2021. We collected the patients' epidemiological information, symptoms, and FilmArray results from their electronic health records. RESULTS: A positive result was observed in 58.6% of patients admitted to the general ward or intensive care unit (ICU) but only in 1.5% of patients in the neonatal ward. Among the patients admitted to the general ward or ICU who tested positive, 93.3% had symptoms suggestive of infections, 44.6% had a sick contact before admission, and 70.5% had siblings. However, 62 (28.2%) out of 220 patients without the four (fever, respiratory, gastrointestinal, and dermal) symptoms also had positive results. Among them, 18 patients with adenovirus and three with respiratory syncytial virus were isolated to private rooms. However, 12 (57.1%) patients were discharged without symptoms suggestive of viral infection. CONCLUSION: Multiplex PCR routine use for all inpatients may lead to excessive management of positive cases because FilmArray cannot quantify microorganisms. Thus, targets for testing should be considered carefully based on patients' symptoms and histories of sick contacts.

Molecular characterization of Candida auris outbreak isolates in Qatar from patients with COVID-19 reveals the emergence of isolates resistant to three classes of antifungal drugs.

OBJECTIVES: During the COVID-19 pandemic in Qatar, many patients who were severely ill were colonized and infected by Candida auris, an invasive multidrug-resistant yeast pathogen that spreads through nosocomial transmission within healthcare facilities. Here, we investigated the molecular epidemiology of these C. auris isolates and the mechanisms associated with antifungal drug resistance. METHODS: Whole genomes of 76 clinical C. auris isolates, including 65 from patients with COVID-19 collected from March 2020 to June 2021, from nine major hospitals were sequenced on Illumina NextSeq. Single nucleotide polymorphisms were used to determine their epidemiological patterns and mechanisms for antifungal resistance. The data were compared with those published prior to the COVID-19 pandemic from 2018 to 2020 in Qatar. RESULTS: Genomic analysis revealed low genetic variability among the isolates from patients with and without COVID-19, confirming a clonal outbreak and ongoing dissemination of C. auris among various healthcare facilities. Based on antifungal susceptibility profiles, more than 70% (22/28) of isolates were resistant to both fluconazole and amphotericin B. Variant analysis revealed the presence of multi-antifungal resistant isolates with prominent amino acid substitutions: Y132F in ERG11 and V704L in CDR1 linked to reduced azole susceptibility and the emergence of echinocandin resistance samples bearing mutations in FKS1 in comparison with pre-COVID-19 pandemic samples. One sample (CAS109) was resistant to three classes of antifungal drugs with a unique premature stop codon in ERG3 and novel mutations in CDR2, which may be associated with elevated amphotericin B and azole resistance. DISCUSSION: Candida auris isolates from patients with COVID-19 and from most patient samples without COVID-19 in Qatar were highly clonal. The data demonstrated the emergence of multidrug-resistant strains that carry novel mutations linked to enhanced resistance to azoles, echinocandins, and amphotericin B. Understanding the epidemiology and drug resistance will inform the infection control strategy and drug therapy.

Equity in the Pandemic Treaty: Access and Benefit-Sharing as a Policy Device or a Rhetorical Device?

Equity is a foundational concept for the new World Health Organization (WHO) Pandemic Treaty. WHO Member States are currently negotiating to turn this undefined concept into tangible outcomes by borrowing a policy mechanism from international environmental law: "access and benefit-sharing" (ABS).

Disease ecology of bats--the Canadian scene

Bats are hosts to a range of pathogens, which include zoonotic pathogens and pathogens of conservation concern. Brock Fenton's research on bat ecology has always balanced clear communication of potential health risks associated with bats and the need to communicate these risks precisely to avoid unnecessary persecution of bats. Here, we integrate Brock's work in the field of disease ecology with that of his students and collaborators and consider the potential advantages of studying disease ecology of bats within the Canadian context. The broad distribution of a few common species across the vast landscape of present-day Canada provides an opportunity to untangle the impacts of environmental variation on host-pathogen interactions and disease severity, particularly in the context of climate change. The varying migratory strategies and social structure of the bat species found in Canada could also facilitate informative interspecific studies to better understand how bat health is affected by interactions among rapid environmental changes, physiological traits, and the social behaviour of different species. We propose a series of priority research questions and approaches that could further our understanding of bat health and disease ecology in Canada, inspired by the work of Brock, his colleagues, and students.

The Biosafety Research Road Map: The Search for Evidence to Support Practices in the Laboratory-SARS-CoV-2.

Introduction: The SARS-CoV-2 virus emerged as a novel virus and is the causative agent of the COVID-19 pandemic. It spreads readily human-to-human through droplets and aerosols. The Biosafety Research Roadmap aims to support the application of laboratory biological risk management by providing an evidence base for biosafety measures. This involves assessing the current biorisk management evidence base, identifying research and capability gaps, and providing recommendations on how an evidence-based approach can support biosafety and biosecurity, including in low-resource settings. Methods: A literature search was conducted to identify potential gaps in biosafety and focused on five main sections, including the route of inoculation/modes of transmission, infectious dose, laboratory-acquired infections, containment releases, and disinfection and decontamination strategies. Results: There are many knowledge gaps related to biosafety and biosecurity due to the SARS-CoV-2 virus's novelty, including infectious dose between variants, personal protective equipment for personnel handling samples while performing rapid diagnostic tests, and laboratory-acquired infections. Detecting vulnerabilities in the biorisk assessment for each agent is essential to contribute to the improvement and development of laboratory biosafety in local and national systems.

Dynamics and profiles of a degenerated reaction-diffusion host-pathogen model with apparent and inapparent infection period.

Inapparent infection plays an important role in the disease spread, which is an infection by a pathogen that causes few or no signs or symptoms of infection in the host. Many pathogens, including HIV, typhoid fever, and coronaviruses such as COVID-19 spread in their host populations through inapparent infection. In this paper, we formulated a degenerated reaction-diffusion host-pathogen model with multiple infection period. We split the infectious individuals into two distinct classes: apparent infectious individuals and inapparent infectious individuals, coming from exposed individuals with a ratio of (1-p) and p, respectively. Some preliminary results and threshold-type results are achieved by detailed mathematical analysis. We also investigate the asymptotic profiles of the positive steady state (PSS) when the diffusion rate of susceptible individuals approaches zero or infinity. When all parameters are all constants, the global attractivity of the constant endemic equilibrium is established. It is verified by numerical simulations that spatial heterogeneity of the transmission rates can enhance the intensity of an epidemic. Especially, the transmission rate of inapparent infectious individuals significantly increases the risk of disease transmission, compared to that of apparent infectious individuals and pathogens in the environment, and we should pay special attentions to how to regulate the inapparent infectious individuals for disease control and prevention, which is consistent with the result on the sensitive analysis to the transmission rates through the normalized forward sensitivity index. We also find that disinfection of the infected environment is an important way to prevent and eliminate the risk of environmental transmission.

Probability of Infectious Disease in Humans during Epidemic

Popular SIR models and their modifications used to generate predictions about epidemics and, specifically, the COVID-19 pandemic, are inadequate. The aim of this study was to find the laws describing the probability of infection in a biological object. Using theoretical methods of research based on the probability theory, we constructed the laws describing the probability of infection in a human depending on the infective dose and considering the temporal characteristics of a given infection. The so-called generalized time-factor law, which factors in the time of onset and the duration of an infectious disease, was found to be the most general. Among its special cases are the law describing the probability of infection developing by some point in time t, depending on the infective dose, and the law that does not factor in the time of onset. The study produced a full list of quantitative characteristics of pathogen virulence. The laws described in the study help to solve practical tasks and should lie at the core of mathematical epidemiological modeling.Copyright © 2022 Obstetrics, Gynecology and Reproduction. All rights reserved.

Antiviral activity of the human endogenous retrovirus-R envelope protein against SARS-CoV-2

Coronavirus-induced disease-19 (COVID-19), caused by SARS-CoV-2, is still a major global health challenge. Human endogenous retroviruses (HERVs) represent retroviral elements that were integrated into the ancestral human genome. HERVs are important in embryonic development as well as in the manifestation of diseases, including cancer, inflammation, and viral infections. Here, we analyze the expression of several HERVs in SARS-CoV-2-infected cells and observe increased activity of HERV-E, HERV-V, HERV-FRD, HERV-MER34, HERV-W, and HERV-K-HML2. In contrast, the HERV-R envelope is downregulated in cell-based models and PBMCs of COVID-19 patients. Overexpression of HERV-R inhibits SARS-CoV-2 replication, suggesting its antiviral activity. Further analyses demonstrate the role of the extracellular signal-regulated kinase (ERK) in regulating HERV-R antiviral activity. Lastly, our data indicate that the crosstalk between ERK and p38 MAPK controls the synthesis of the HERV-R envelope protein, which in turn modulates SARS-CoV-2 replication. These findings suggest the role of the HERV-R envelope as a prosurvival host factor against SARS-CoV-2 and illustrate a possible advantage of integration and evolutionary maintenance of retroviral elements in the human genome.Copyright © 2023 The Authors.

Microbiology and Bioterrorism

It's been 2 decades since the posting of the anthrax letters in the United States in 2001. This event marked a pivotal point in our history. It highlighted the vulnerability of modern society to acts of bioterrorism and set countries on a course to develop capabilities to pre-empt, prevent, react to, investigate, and recover from acts of bioterrorism. The current COVID-19 pandemic is a stark reminder of the enormity of the impact that the release of a biological agent, natural or otherwise, can have on an immunological naïve society. The purpose of this article is to describe how microbiology is applied in the investigation of bioterrorism, highlighting the modern advances in technology, particularly the DNA technologies, which have assisted this discipline as a forensic practice. © 2023 Elsevier Ltd. All rights reserved.