Infectious Disease Agents Research Articles

Exploring hospital resilience protective or risk factors: lessons for future disaster response efforts.

Hospital resilience is essential in responding to disasters, but current research focuses mainly on frameworks and models rather than the protection of resilience and analysis of risk factors during public health emergencies. This study aims to examine the development of resilience in Chinese frontline hospitals during the initial COVID-19 outbreak in 2020, providing insights for future disaster response efforts. We conducted interviews with 26 hospital staff members who were involved in the initial response to the COVID-19 outbreak in China. We used a semi-structured interview approach and employed purposive sampling and snowball sampling techniques. The interview outline was guided by the 'Action Framework' proposed by the World Health Organization (WHO) for responding to infectious disease emergencies. This framework includes dimensions such as command, surveillance, risk communication, medical response, and public health response. We analyzed the collected data using Colaizzi's seven-step data analysis method and the template analysis method. WHO's 'action framework' effectively highlights the factors that contribute to hospital resilience. While medical response, including the availability of materials and facilities, the use of information technology, and the capacity for infectious disease diagnosis and treatment, remains crucial, other important aspects include awareness and beliefs about infections, treatment experience, interdisciplinary collaboration, and more. Additionally, it is essential to establish an intelligent command system, foster trusting partnerships between teams, improve monitoring capabilities for infectious disease agents, enhance risk communication through information synchronization and transparency, strengthen infection control planning, and improve environmental disinfection capabilities for effective public health emergency response. These contradictions significantly impact the enhancement of hospital resilience in dealing with major infectious disease outbreaks. In responding to sudden major infectious diseases, hospitals play a vital role within the healthcare system. Enhancing hospital resilience involves more than just improving treatment capabilities. It also requires effective command coordination at the hospital level, infection control planning, and the deployment of intelligent equipment. Additionally, planning for effective communication and coordination between hospitals, communities, and the national healthcare system can further enhance hospital resilience.

Scientific justification of Mycobacterium avium survival in natural environment of Republic of Dagestan

Contamination of the environment with the infectious animal disease agents is still a pressing problem for the poultry farms. Mycobacterium avium can grow and replicate in organic wastes from the poultry farms for a long time thus contaminating vast adjacent areas and being the source of infection not only for wild and domestic animals but also for humans. The studies were aimed at the examination of the duration of Mycobacterium avium survival in the natural environment in two geographical regions of the Republic of Dagestan characterized by different soil and climate. Samples of Mycobacterium avium-contaminated feces and soil collected from pastures and farmyards (on the surface and from 5 cm depth) were tested. The experiments demonstrated that pathogenic for chickens mycobacteria survived for up to 30 days in the samples collected in the sub-mountainous areas in summertime, when the air temperature ranged from 15.1 to 30 °С, land surface temperature – from 17 to 38 °С, air humidity – from 44 to 94% and average monthly precipitation amounted to 1.5 mm. From September to May, with the air temperature ranging from –10.8 to +25 °C, land surface temperature from –14 to +30 °C, air humidity 26–100% and average precipitation 0.39 mm, the bacteria survived for up to 213 days on the soil surface on the pastures and farmyards, and for up to 243 days at the depth of 5 cm and in the feces. In the plain area, in the same time period in the slightly saline soil with high humus content and at air temperature from –11.9 to +27.3 °C, soil temperature from –13 to +45 °C, air humidity from 37 to 100% and average precipitation 20.4 mm, Mycobacterium avium survived just like in the sub-mountainous area, i.e. for 213 and 243 days, respectively. The post-mortem lesions in the internal organs of the poultry corresponded to the tuberculosis clinical signs in 86 of 171 birds (50.3%). The study results will allow for the development of the optimal algorithm for animal health and management measures aimed at tuberculosis eradication on the poultry farms.

Recent Advances in Enzyme Inhibition: A Pharmacological Review

Abstract: Enzyme inhibition is a crucial mechanism for regulating biological processes and developing therapeutic interventions. This pharmacological review summarizes recent advances in enzyme inhibition, focusing on key developments and their implications for drug discovery and therapeutic strategies. It explains basic ideas, including the different kinds of inhibitors and how they work, and looks at recent advances in small-molecule inhibitor design, fragment-based drug discovery, and virtual screening techniques. The review also highlights the advances in targeting specific enzyme families, explaining the structural basis of enzyme-inhibitor interactions, optimizing inhibitor potency, selectivity, and pharmacokinetic properties, and new trends in enzyme inhibition. The clinical implications of recent advances in enzyme inhibition include the development of novel therapeutic agents for diseases like cancer, infectious diseases, and neurological disorders. The review addresses challenges and future directions in the field, such as optimizing drug safety, resistance mechanisms, and personalized medicine approaches. Overall, the insights provided in this review may inspire further research and collaborations to accelerate the translation of enzyme inhibitors into effective clinical treatments.

Resistance of a mixed bacterial culture isolated from bee dysbiosis to disinfectant in laboratory conditions

Disinfection is one of the components of preventive actions to prevent disease in animals by infectious agents. Through the elimination of agents of infectious diseases in the environment, it is able to interrupt the mechanisms of the epizootic process. For the development of beekeeping and obtaining quality and products, it is necessary to carry out activities in apiaries, which include disinfection. The introduction of new disinfectants in the field is possible after preliminary laboratory tests. The aim of our research objective to investigate the resistance of a mixed bacterial culture isolated from bees with the symptoms of dysbiosis to disinfectant under laboratory conditions. Bacteriological investigations carried out in Petri dishes using meat-peptone agar and Mueller-Hinton agar.  The disinfectant diluted with distilled water at concentrations of 0.25 %, 0.5 %, 1,25 % and 2,5 %. On the Mueller Hinton agar, the bacterial elimination zones recorded at 1.25 % (11,6 ± 0,45 mm) and 2.5 % (12,4 ± 0,27 mm) concentration of disinfectant at 1 day of investigation, and 7,4 ± 0,27 mm (1,25 %), 11,2 ± 0,42 mm (2.5 %) at 72 hours of the experiment, respectively. In addition, the bacterial growth inhibition effect increased with experimental time and ranged from 24.0 ± 0.35 mm (0.5 %) to 28.2 ± 0.22 mm (2.5 %) on day 3 of the study. Bacteriostatic and bactericidal effects appeared to be less pronounced on meat-peptone agar. The highest diameters of inhibition of the processes of reproduction and development of microorganisms from mixed microbial association on this medium were recorded at 1.25 % and 2.5 % concentrations of the disinfectant at the 3rd day of the investigation with diameters of the zones of inhibition of growth 15.6 ± 0.45 mm and 26.4 ± 0.27 mm, respectively. The specificity of diffusion of the investigated active substance from the discs into the agar medium thickness was also noted. This effect has a varying effect on infectious agents in in vitro experiments. Thus bacteriological laboratory experiments should be performed on several culture media in purpose of obtaining accurate results. The analysis of the obtained results indicates the demonstration of antimicrobial effect of the investigated disinfectant against mixed bacterial culture in the form of bactericidal and bacteriostatic actions. Therefore, a promising direction of research for veterinary doctors and apiary business owners is the search for effective and efficient disinfectants. Laboratory investigation of the activity of a remedy are the first step before it is approbation.

Genetic Marker Detection of Natural-Focal Infectious Disease Pathogens in Samples of Ixodidae Ticks, Collected on the Territory of the Republic of Guinea

The circulation of a rather wide range of pathogens of natural-focal infectious diseases transmitted by ticks was detected in West Africa at different points of time: Borrelia, Rickettsia, Coxiella, Crimean-Congo hemorrhagic fever (CCHF), Bhanja, and bluetongue viruses, etc. Current epidemiological and epizootiological situation on natural-focal infectious diseases on the territory of the Republic of Guinea is not entirely clarified.The aim of this work was to identify genetic markers (RNA/DNA) of natural-focal infectious disease agents in samples of Ixodidae ticks collected in the Republic of Guinea, and to determine the spectrum of pathogens circulating in various landscape-geographical zones of the country.Materials and methods. To conduct research on the territory of all landscape-geographical zones of the Republic of Guinea, 4695 specimens of Ixodidae ticks of 11 species were collected. Taking into account the species appurtenance, gender, phase of development, as well as the site of collection, a panel of 1645 samples was compiled. Genetic markers of Crimean-Congo hemorrhagic fever and tick-borne encephalitis viruses, as well as Borrelia burgdorferi s.l., Ehrlichia chaffeensis, Ehrlichia muris, Anaplasma phagocytophilum, Coxiella burnetii, Rickettsia of the tick-borne spotted fever (TBSF) group, and Francisella tularensis were detected using polymerase chain reaction (PCR) and reverse transcription polymerase chain reaction (RT-PCR).Results and discussion. The following markers of natural-focal disease agents were found in the Ixodidae tick suspensions: DNA of Rickettsia of the TBSF group (25.6 % of all samples studied), DNA of C. burnetii (6.2 %), cDNA of B. burgdorferi s.l. (9.1 %), and RNA of the CCHF virus (2.5 %). The listed spectrum of pathogens has been registered in all landscape-geographical zones of Guinea. Genetic markers of tularemia, anaplasmosis, ehrlichiosis and tick-borne encephalitis pathogens have not been identified in this study. The results obtained made it possible to clarify the probable spectrum of tick-borne diseases in the territory of the Republic of Guinea, determined the need for further study of the circulation of natural-focal infectious disease agents in West Africa and conducting regular epizootiological monitoring.

Fate and Proliferation of Vancomycin Resistance Genes in Two Typical Pharmaceutical Wastewater Treatment Plants

The emergence of vancomycin-resistant Enterococcus (VRE) and vancomycin resistance genes (VRGs) complicates the application of vancomycin, which is a last-line agent for human infectious diseases, and pharmaceutical wastewater treatment plants (PWWTPs) are widely thought to be important sources of corresponding antibiotic resistance genes (ARGs). In this study, two VRGs (vanA and vanB) were evaluated in two PWWTPs using quantitative polymerase chain reaction (qPCR) analysis to characterize the occurrence and fate of VRGs. The VRG concentration tended to decrease throughout all processing stages, while anaerobic treatment promoted the propagation of antibiotic-resistant bacteria and led to an increase in VRG abundance. Finally, the absolute concentrations of vanA and vanB exceeded 104 copies/mL in the effluents, and a significant amount of VRGs was transferred to sludge at 1.68 × 1017 copies/d. Redundancy analysis demonstrated that the relative abundance of ARGs was significantly correlated with the concentrations of vancomycin and COD. Furthermore, the relative abundance of vanA was increased in wastewater with multiple antibiotics, while the relative abundance of vanB only increased in the presence of vancomycin. This observation implied different intrinsic resistance mechanisms for different VRG subtypes. Overall, in this report, we describe the first comprehensive study on the fate and behavior of VRGs with different physicochemical or biochemical treatments and different antibiotic selection pressures in PWWTPs; this report provides important references for the environmental spread of VRGs.

Neurotropic enteroviruses (Picornaviridae: Enterovirus): predominant types, basis of neurovirulence.

Enteroviruses are one of the most common causative agents of infectious diseases of the central nervous system. They are characterized by genetic variability, the ability to infect a wide range of cells, including brain microglial cells and astrocytes, and persist in the central nervous system tissue, causing delayed and chronic diseases. The review presents data on the basis of neurovirulence of non-polio enteroviruses and the most common pathogens causing enteroviral neuroinfections.

An Integrated ddPCR Lab-on-a-Disc Device for Rapid Screening of Infectious Diseases.

Digital droplet PCR (ddPCR) is a powerful amplification technique for absolute quantification of viral nucleic acids. Although commercial ddPCR devices are effective in the lab bench tests, they cannot meet current urgent requirements for on-site and rapid screening for patients. Here, we have developed a portable and fully integrated lab-on-a-disc (LOAD) device for quantitively screening infectious disease agents. Our designed LOAD device has integrated (i) microfluidics chips, (ii) a transparent circulating oil-based heat exchanger, and (iii) an on-disc transmitted-light fluorescent imaging system into one compact and portable box. Thus, droplet generation, PCR thermocycling, and analysis can be achieved in a single LOAD device. This feature is a significant attribute for the current clinical application of disease screening. For this custom-built ddPCR setup, we have first demonstrated the loading and ddPCR amplification ability by using influenza A virus-specific DNA fragments with different concentrations (diluted from the original concentration to 107 times), followed by analyzing the droplets with an external fluorescence microscope as a standard calibration test. The measured DNA concentration is linearly related to the gradient-dilution factor, which validated the precise quantification for the samples. In addition to the calibration tests using DNA fragments, we also employed this ddPCR-LOAD device for clinical samples with different viruses. Infectious samples containing five different viruses, including influenza A virus (IAV), respiratory syncytial virus (RSV), varicella zoster virus (VZV), Zika virus (ZIKV), and adenovirus (ADV), were injected into the device, followed by analyzing the droplets with an external fluorescence microscope with the lowest detected concentration of 20.24 copies/µL. Finally, we demonstrated the proof-of-concept detection of clinical samples of IAV using the on-disc fluorescence imaging system in our fully integrated device, which proves the capability of this device in clinical sample detection. We anticipate that this integrated ddPCR-LOAD device will become a flexible tool for on-site disease detection.

The Identification of a Novel Spider Toxin Peptide, Lycotoxin-Pa2a, with Antibacterial and Anti-Inflammatory Activities.

With the increasing challenge of controlling infectious diseases due to the emergence of antibiotic-resistant strains, the importance of discovering new antimicrobial agents is rapidly increasing. Animal venoms contain a variety of functional peptides, making them a promising platform for pharmaceutical development. In this study, a novel toxin peptide with antibacterial and anti-inflammatory activities was discovered from the spider venom gland transcriptome by implementing computational approaches. Lycotoxin-Pa2a (Lytx-Pa2a) showed homology to known-spider toxin, where functional prediction indicated the potential of both antibacterial and anti-inflammatory peptides without hemolytic activity. The colony-forming assay and minimum inhibitory concentration test showed that Lytx-Pa2a exhibited comparable or stronger antibacterial activity against pathogenic strains than melittin. Following mechanistic studies revealed that Lytx-Pa2a disrupts both cytoplasmic and outer membranes of bacteria while simultaneously inducing the accumulation of reactive oxygen species. The peptide exerted no significant toxicity when treated to human primary cells, murine macrophages, and bovine red blood cells. Moreover, Lytx-Pa2a alleviated lipopolysaccharide-induced inflammation in mouse macrophages by suppressing the expression of inflammatory mediators. These findings not only suggested that Lytx-Pa2a with dual activity can be utilized as a new antimicrobial agent for infectious diseases but also demonstrated the implementation of in silico methods for discovering a novel functional peptide, which may enhance the future utilization of biological resources.

Molecular physiological characterization of the dynamics of persister formation in Staphylococcus aureus.

Bacteria possess the ability to enter a growth-arrested state known as persistence in order to survive antibiotic exposure. Clinically, persisters are regarded as the main causative agents for chronic and recurrent infectious diseases. To combat this antibiotic-tolerant population, a better understanding of the molecular physiology of persisters is required. In this study, we collected samples at different stages of the biphasic kill curve to reveal the dynamics of the cellular molecular changes that occur in the process of persister formation. After exposure to antibiotics with different modes of action, namely, vancomycin and enrofloxacin, similar persister levels were obtained. Both shared and distinct stress responses were enriched for the respective persister populations. However, the dynamics of the presence of proteins linked to the persister phenotype throughout the biphasic kill curve and the molecular profiles in a stable persistent population did show large differences, depending on the antibiotic used. This suggests that persisters at the molecular level are highly stress specific, emphasizing the importance of characterizing persisters generated under different stress conditions. Additionally, although generated persisters exhibited cross-tolerance toward tested antibiotics, combined therapies were demonstrated to be a promising approach to reduce persister levels. In conclusion, this investigation sheds light on the stress-specific nature of persisters, highlighting the necessity of tailored treatment approaches and the potential of combined therapy.

A metatranscriptomic evaluation of viruses in field-collected bed bugs.

Cimex lectularius, known as the common bed bug, is a widespread hematophagous human ectoparasite and urban pest that is not known to be a vector of any human infectious disease agents. However, few studies in the era of molecular biology have profiled the microorganisms harbored by field populations of bed bugs. The objective of this study was to examine the viruses present in a large sampling of common bed bugs and related bat bugs (Cimex pipistrelle). RNA sequencing was undertaken on an international sampling of > 500 field-collected bugs, and multiple workflows were used to assemble contigs and query these against reference nucleotide databases to identify viral genomes. Shuangao bed bug virus 2, an uncharacterized rhabdovirus previously discovered in Cimex hemipterus from China, was found in several bed bug pools from the USA and Europe, as well as in C. pipistrelle, suggesting that this virus is common among bed bug populations. In addition, Shuangao bed bug virus 1 was detected in a bed bug pool from China, and sequences matching Enterobacteria phage P7 were found in all bed bug pools, indicating the ubiquitous presence of phage-derived elements in the genome of the bed bug or its enterobacterial symbiont. However, viral diversity was low in bed bugs in our study, as no other viral genomes were detected with significant coverage. These results provide evidence against frequent virus infection in bed bugs. Nonetheless, our investigation had several important limitations, and additional studies should be conducted to better understand the prevalence and composition of viruses in bed bugs. Most notably, our study largely focused on insects from urban areas in industrialized nations, thus likely missing infrequent virus infections and those that could occur in rural or tropical environments or developing nations.

Сравнительная оценка токсичности и вирулицидных свойств дезинфектантов, применяемых при работе с вирусом SARS-CoV-2 в изолированных вирусологических лабораториях

The choice of disinfectants and their combinations for the final disinfection of the premises of «infectious» areas of laboratories of biosafety level 3–4, in which work is carried out with viruses with epidemic potential, is important for reducing the toxic effect of these disinfectants on personnel while maintaining 100?% disinfection efficiency. Purpose of the study: to study the toxicity of disinfectants of different groups for cell culture, to select a toxicity neutralizer, to study the virucidal activity of these disinfectants and their combinations against the SARS-CoV-2 virus. Materials and methods: experimental studies were carried out using the reference strain of coronavirus SARS-CoV-2, namely the hCoV-19/Australia/VIC01/2020 (AUS) strain (Wuhan variant), obtained from the State Collection of Causative Agents of Viral Infectious Diseases and Rickettsial Diseases, functioning on the basis of the Federal Budgetary Institution State Scientific Center for Virology and Biotechnology «Vector» of Rospotrebnadzor. The residual infectious activity of the virus was determined by titrating samples in cell culture. To conduct the research, we used a Vero E6 cell culture obtained from the Collection of Cell Cultures of the Federal Budgetary Institution of Scientific Research Center for Virology and Biochemistry «Vector» of Rospotrebnadzor in the form of a 2-day monolayer with a confluency of 95–100?%. Results. As a result of the studies, experimental data were obtained on the dynamics of the virucidal activity of different groups of disinfectants and their combinations against the SARS-CoV-2 virus. The degree of toxicity of disinfectants for Vero E6 cell culture is shown. Optimal combinations of disinfectants and a 40?% aqueous solution of formaldehyde (hereinafter referred to as formalin) have been selected, increasing its disinfection efficiency at an initial concentration halved, which can be used for final disinfection treatment of the premises of isolated virology laboratories conducting work with the SARS-CoV- coronavirus. Conclusion. The results obtained indicate that when using selected combinations of disinfectants to carry out final disinfection with formaldehyde vapors formed during the evaporation of formaldehyde as a result of its heating, a twofold decrease in the initial concentration of formalin is possible, leading to a decrease in its toxic effect on personnel, while maintaining 100?% efficiency disinfection. Keywords: disinfection, disinfectants, formaldehyde, SARS-CoV-2 coronavirus, disinfection efficiency, cytotoxicity.

Antibacterial Activity of River Water Bacteriophage against Multidrug-resistant Gram-negative Bacteria, An In vitro Study

Microbes show a high antimicrobial resistance due to a high rate of mutations predisposed by many factors, especially the abuse of antibiotics. Therefore, there is a great need for an alternative therapeutic agent for infectious diseases caused by microbes resistant to antibiotics. Bacteriophages are viruses parasitizing microbes, that got a big scientist’s attention due to their ability as an alternative therapy for severe bacterial infections. This study is devoted to identifying bacteriophage from river water on tested pathogenic isolates isolated from clinical cases of UTI in vitro and finding out the effect of phage on these bacterial isolates as an initial step of further in vivo phage therapeutic study on the same tested isolates. The results showed a significant bactericidal effect of the isolated bacteriophages against the pathogenic bacterial isolates.

Epidemiologic investigation and genetic characterization of canine respiratory coronavirus in the Southeastern United States.

Canine respiratory coronavirus (CRCoV) is one of the main causative agents of canine infectious respiratory disease (CIRD), an illness whose epidemiology is poorly understood. We assessed the prevalence, risk factors, and genetic characterization of CRCoV in privately owned dogs in the Southeastern United States. We PCR-screened 189 nasal swabs from dogs with and without CIRD clinical signs for 9 CIRD-related pathogens, including CRCoV; 14% of dogs, all diagnosed with CIRD, were positive for CRCoV, with a significantly higher rate of cases in younger dogs and during warmer weather. Notably, the presence of CRCoV, alone or in coinfection with other CIRD pathogens, was statistically associated with a worse prognosis. We estimated a CRCoV seroprevalence of 23.7% retrospectively from 540 serum samples, with no statistical association to dog age, sex, or season, but with a significantly higher presence in urban counties. Additionally, the genomes of 6 CRCoVs were obtained from positive samples using an in-house developed targeted amplicon-based approach specific to CRCoV. Subsequent phylogeny clustered their genomes in 2 distinct genomic groups, with most isolates sharing a higher similarity with CRCoVs from Sweden and only 1 more closely related to CRCoVs from Asia. We provide new insights into CIRD and CRCoV epidemiology in the Southeastern United States and further support the association of CRCoV with more severe cases of CIRD. Additionally, we developed and successfully tested a new amplicon-based approach for whole-genome sequencing of CRCoV that can be used to further investigate the genetic diversity within CRCoVs.

Evidence for Bartonella quintana in Lice Collected from the Clothes of Ethiopian Homeless Individuals.

Human lice, Pediculus humanus, can transmit various pathogens, including Bartonella quintana, Borrelia recurrentis, and Rickettsia prowazekii. Xenosurveillance is an epidemiological approach to assessing human infection risks performed by screening vectors of infectious disease agents. In the proof-of-principle study reported herein, the DNA of 23 human lice was collected from the clothes of 30 homeless Ethiopian individuals. These samples were assessed using 16S rRNA gene-specific pan-eubacterial PCR for screening, followed by Bartonella genus 16S-23S internal transcribed spacer (ITS) sequence-specific PCR, Bartonella genus gltA gene-specific PCR, and 16S rRNA gene PCR with specificity for relapsing-fever-associated Borrelia spp. with subsequent sequencing of the amplicons. In one sample, the pan-eubacterial 16S rRNA gene-specific screening PCR, the Bartonella genus 16S-23S ITS sequence-specific PCR, and the Bartonella genus gltA gene-specific PCR allowed for the sequencing of B. quintana-specific amplicons. In two additional samples, Bartonella genus gltA gene-specific PCR also provided sequences showing 100% sequence identity with B. quintana. In total, 3/23 (13.0%) of the assessed lice were found to be positive for B. quintana. Correlating clinical data were not available; however, the assessment confirmed the presence of B. quintana in the local louse population and thus an associated infection pressure. Larger-sized cross-sectional studies seem advisable to more reliably quantify the infection risk of lice-infested local individuals. The need for prevention by providing opportunities to maintain standard hygiene for Ethiopian homeless individuals is stressed by the reported findings, especially in light of the ongoing migration of refugees.

Feline Coronavirus Infection: Genomics and Epizootology

Introduction. The issue of coronavirus infection prevalence in cats is still acute. Particular danger of infecting the animals lies in possible mutations of the virus, the asymptomatic course of the disease, high prevalence of the virus carriage in cats and development of the viral peritonitis in some of the specimens often causing the death of animals. The aim of this work is to study the relation between the keeping conditions and the coronavirus infection prevalence in cat populations in different countries, as well as the possibility of the viral peritonitis development in this species of animal.Materials and Methods. The analysis of the Russian and foreign sources published before March 2023 was carried out. Based on the research made by the scientists from the Netherlands, Korea, Germany, Taiwan, Australia, Sweden, Czech Republic, Malaysia and Turkey, the relation between the cat keeping conditions and the coronavirus infection prevalence in their populations was studied and the brief characteristics of the disease was given.Results. Based on the analysis of the several epizootological study results, it was concluded that the rate of companion cats infection with the coronavirus reached 80 %, and one of the highest rates was recorded in Germany: 76.5 % (Confidence Interval (CI) 95 %: 69.8 %; 82.2 %) and 84 % (CI 95 %: 73.3 %; 94.9 %), respectively. Coronavirus infection prevalence in cats kept in groups, as well as in stray cats was significantly higher than in animals kept in isolation.Discussion and Conclusions. Studying the FCoV prevalence in various cat populations revealed its direct dependence from the keeping conditions. The need to control and limit the number of animals that are kept together, as well as to comply with all the keeping and quarantine standards, is shown, and could become the way for the cat owners to suppress the infectious disease agents transmission.

Rural-Urban Inequities in Tuberculosis-Related Practices in Equatorial Guinea.

Tuberculosis (TB) is one of the leading causes of mortality from a single infectious disease agent. Equatorial Guinea is a country with high estimated TB incidence in 2021 (275 cases per 100,000 population) and low TB case detection (42%). Early diagnosis and prompt treatment are crucial for TB control. Failure to seek adequate health care increases the disease's transmission and leads to poor treatment outcome, the mortality, even for easily manageable conditions. Information regarding community management of TB and treatment-seeking patterns in Equatorial Guinea is rare. The aim of this study was to explore differences in TB health-seeking behaviour among urban and rural population TB cases in Equatorial Guinea and the factors associated with this behaviour. A national cross-sectional study of 770 household caregivers was conducted in 2020 in Equatorial Guinea using multistage stratified sampling. The 284 caregivers that reported having had a TB case in their family were included in this study. A practice index was created. Poisson regression with robust variance was performed with the practices index as dependent variable to assess the factors associated with the health-seeking behaviour. Most of the cases (65%) have had good TB health-seeking practices. However, 23.2% of TB cases reported having abandoned treatment before 6 months. A higher probability of having good TB practices was observed with being women, aged and living in rural area. Those who were TB cases themselves have heard about TB on the radio, and had high knowledge about TB, hand also good practices. Disparities in tuberculosis health-seeking behaviour between rural and urban populations highlight the challenges existing in the fight against this infectious disease. The National Tuberculosis Control Program has to reinforce the health system needs to strengthen the follow-up of TB patients taking into account the population at risk of inappropriate TB behaviour. Not applicable.

Improved protocol for Bst polymerase and reverse transcriptase production and application to a point-of-care diagnostics system.

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has raised awareness in the scientific community about the importance of being prepared for sanitary emergencies. Many measures implemented during the COVID pandemic are now being expanded to other applications. In the field of molecular and immunological diagnostics, the need to massively test the population worldwide resulted in the application of a variety of methods to detect viral infection. Besides gold standard reverse transcription quantitative polymerase chain reaction (RT-qPCR), the use of reverse transcription loop-mediated isothermal amplification (RT-LAMP) arose as an alternative and sensitive method to amplify and detect viral genetic material. We have used openly available protocols and have improved the protein production of RT-LAMP enzymes Bst polymerase and HIV-reverse transcriptase. To optimize enzyme production, we tested different protein tags, and we shortened the protein purification protocol, resulting in reduced processing time and handling of the enzymes and, thus, preserved the protein activity with high purity. The enzymes showed significant stability at 4 °C and 25 °C, over 60 days, and were highly reliable when used as a one-step RT-LAMP reaction in a portable point-of-care device with clinical samples. The enzymes and the reaction setup can be further expanded to detect other infectious diseases agents.

Regulation of σB-Dependent Biofilm Formation in Staphylococcus aureus through Strain-Specific Signaling Induced by Diosgenin.

Staphylococcus aureus is a commensal skin bacterium and a causative agent of infectious diseases. Biofilm formation in S. aureus is a mechanism that facilitates the emergence of resistant strains. This study proposes a mechanism for the regulation of biofilm formation in S. aureus through strain-specific physiological changes induced by the plant steroid diosgenin. A comparison of diosgenin-induced changes in the expression of regulatory genes associated with physiological changes revealed the intracellular regulatory mechanisms involved in biofilm formation. Diosgenin reduced biofilm formation in S. aureus ATCC 6538 and methicillin-resistant S. aureus (MRSA) CCARM 3090 by 39% and 61%, respectively. Conversely, it increased biofilm formation in S. aureus ATCC 29213 and MRSA CCARM 3820 by 186% and 582%, respectively. Cell surface hydrophobicity and extracellular protein and carbohydrate contents changed in a strain-specific manner in response to biofilm formation. An assessment of the changes in gene expression associated with biofilm formation revealed that diosgenin treatment decreased the expression of icaA and spa and increased the expression of RNAIII, agrA, sarA, and sigB in S. aureus ATCC 6538 and MRSA CCARM 3090; however, contrasting gene expression changes were noted in S. aureus ATCC 29213 and MRSA CCARM 3820. These results suggest that a regulatory mechanism of biofilm formation is that activated sigB expression sequentially increases the expression of sarA, agrA, and RNAIII. This increased RNAIII expression decreases the expression of spa, a surface-associated adhesion factor. An additional regulatory mechanism of biofilm formation is that activated sigB expression decreases the expression of an unknown regulator that increases the expression of icaA. This in turn decreases the expression of icaA, which decreases the synthesis of polysaccharide intercellular adhesins and ultimately inhibits biofilm formation. By assessing strain-specific contrasting regulatory signals induced by diosgenin in S. aureus without gene mutation, this study elucidated the signal transduction mechanisms that regulate biofilm formation based on physiological and gene expression changes.

Understanding the interface between European wild boar (Sus scrofa) and domestic pigs (Sus scrofa domesticus) in Sweden through a questionnaire study

BackgroundIn recent years, the wildlife/livestock interface has attracted increased attention due to disease transmission between wild and domestic animal populations. The ongoing spread of African swine fever (ASF) in European wild boar (Sus scrofa) emphasize the need for further understanding of the wildlife/livestock interface to prevent disease spill-over between the wild and domestic populations. Although wild boar may also act as a potential source for other infectious disease agents, ASF is currently the most severe threat from wild boar to domestic pigs. To gather information on the wild boar situation at commercial pig producing farms in Sweden, a digital questionnaire survey was distributed through the animal health services.ResultsMost pigs produced for commercial purposes in Sweden are raised without outdoor access. Of the 211 responding pig producers, 80% saw wild boar or signs of wild boar activity in the vicinity of their farm at least once during the year. Observations were significantly correlated with geographical region, but there was no correlation between farm characteristics (farm size, main type of production, outdoor access) and observed wild boar presence or proximity. However, a reported higher frequency of wild boar observations was positively correlated with the observations being made in closer proximity to the farm.Hunting and strategic baiting were the most common mitigation strategies used to keep wild boar at bay. Of the 14 farms raising pigs with outdoor access, 12 responded that these pigs could be raised solely indoors if needed.Pigs with outdoor access are required to be fenced in, but double fencing in these outdoor pig enclosures was not practiced by all. A perimeter fence surrounding any type of pig farm was very rare. More than half of the producers that grew crops with intended use for pigs reported crop damage by wild boar.ConclusionThis study shows that although pigs raised for commercial purposes in Sweden are, to a large extent, kept indoors the potential for indirect contact with wild boar exists and must be considered. Variable local situations regarding wild boar abundance may require an adaptive approach regarding biosecurity efforts.