Antibody Response after SARS-CoV-2 Infection with the Delta and Omicron Variant.

The SARS-CoV-2 virus caused a worldwide COVID-19 pandemic. So far, 6,120,834 confirmed cases of COVID-19 with 116,773 deaths have been reported in Poland. According to WHO, a total of 54,662,485 vaccine doses have been administered. New variants emerge that become dominant. The aim of this study was a comparison of antibody level after infection caused by Delta and Omicron variants. The study included 203 persons who underwent mild COVID-19 despite two doses of vaccine. The obtained results indicate that a significantly lower titer was observed in patients with the Omicron variant infection. Therefore, these patients may be at risk of reinfection with new strains of the Omicron variant. Due to the possibility of reinfection, booster vaccinations are necessary. Further epidemiological and clinical studies are necessary to develop new prevention strategies.

Antibodies to NCP, RBD and S2 SARS-CoV-2 in Vaccinated and Unvaccinated Healthcare Workers.

In a few months, the SARS-CoV-2 virus caused a worldwide COVID-19 pandemic. In Poland, 6 million cases of the disease and 113,000 deaths from COVID-19 have been reported. Healthcare workers (HCWs) constitute one of the main COVID-19 risk groups. The Microblot-Array COVID-19 IgG assay was used to detect antibodies against three major SARS-CoV-2 antigens: nucleocapsid (NCP), RBD, and Spike 2 (S2). The aim of our study was to determine the seroprevalence and titer of anti-SARS-CoV-2 IgG antibodies-NCP, RBD, and S2-as markers of the humoral response in vaccinated and unvaccinated HCWs. The study included 203 persons who were divided into four groups: "COVID-19 Vaccinated", "COVID-19 Unvaccinated", "Non-COVID-19 Vaccinated", and "Non-COVID-19 Unvaccinated". The obtained results indicate that both seroprevalence and the antibody titer are the highest in the "COVID-19 Vaccinated" group. There is no so-called sterile vaccination, and after 6 months from the second dose of vaccine, most vaccinated people have a fairly high level of antibodies. We suggest that multiple vaccination and continuous testing are necessary. The Microblot-Array assay can distinguish between antibodies acquired after infection and/or vaccination.

Lessons learned from 2001-2021 - from the bioterrorism to the pandemic era.

INTRODUCTION AND OBJECTIVE: The aim of the study was to analyze available literature on the development of biological warfare and combating the SARS CoV-2 pandemic. Against the background of contemporary threats from biological factors, the strengths and weaknesses of response in the event of a bioterrorist attack during the ongoing COVID-19 pandemic have been identified. The scope and importance of international cooperation in the fight against the pandemic is assessed. REVIEW METHODS: The more important literature on bioterrorism, biological weapons and the COVID-19 pandemic, both from earlier work and recent publications, was analyzed, emphasizing new threats and adequate defence against them. BRIEF DESCRIPTION OF THE STATE OF KNOWLEDGE: The bio-warfare threat and the current COVID 19 pandemic that has hit mankind on a global scale has clearly shown how dangerous biological agents are and what effects they can cause, negatively affecting every sphere of human activity with catastrophic consequences. Data on examples of bioterrorist attacks carried out and research on the development of biological weapons and methods of combating pandemic COVID-19, were reviewed. New threats related to technological development,including those resulting from genetic manipulation, biosynthesis, and modern means of delivery, are pointed out. Attention has been paid to the implications of controlling the proliferation of biological weapons and the issues of international cooperation in the fight against bioterrorism and the COVD-19 pandemic. SUMMARY: The lesson learned clearly demonstrates the weakness of states in responding to such threats. The risks of uncontrolled scientific advances are still underestimated. Appropriate international control measures must be taken urgently to prepare for new pandemics, bioterrorist attacks, and the possibility of using modern biological weapons.

The analysis of Fe-dependent serum enzymes in severe COVID-19 with a pulmonary thrombotic event.

Introduction: COVID-19 patients in critical condition requiring ICU admission are more likely to experience thromboembolic complications, especially pulmonary embolism. Since the outbreak of coronavirus disease 2019 (COVID-19), clinicians have struggled with the attempt to diagnose and manage the severe and fatal complications of COVID-19 appropriately. Several reports have described significant procoagulatory events, including life-threatening pulmonary embolism, in these patients. The aim of the study was to analyze the results of selected serum enzymes in patients with a radiologically confirmed pulmonary thrombotic event based on the pulmonary tissue involvement assessed in a computed tomography (CT) scan. Material and methods: The retrospective study covered a group of 226 COVID-19 patients. Groups were divided based on the degree of lung tissue involvement in CT examinations, including patients with confirmed pulmonary embolism. The analyzed group consisted of 136 men and 90 women with mean age of 70 years. Results: The group consisted of patients with < 50% of lung volume changes who had higher parameter values in each analyzed parameter, except red blood cells (RBC) (p < 0.05). Especially, the level of ferritin was much higher in the first group (p = 0.000008). Elevated ferritin levels were observed in all patients with lung tissue involvement. Discussion: This line of research is critical in order to assess the predisposing conditions for pulmonary embolism occurrence in COVID-19, which can be used as a predictive factor for course of the disease. The conducted research will resolve whether there is a relationship between the selected laboratory parameters and the occurrence of pulmonary embolism in patients with COVID-19. Conclusions: The study demonstrated that elevated levels of several inflammatory and thrombotic parameters such as ferritin, D-dimer, C-reactive protein (CRP) as well as hemoglobin do not correlate with the degree of lung tissue involvement in the computed tomography image.

Review of studies on SARS-CoV-2 infection inhibitors.

INTRODUCTION AND OBJECTIVE: COVID-19 is a human infectious disease manifested by acute respiratory syndrome. On 30 January, 2020, the Word Heath Organization (WHO) declared a COVID-19 pandemic. The purpose of this article is to review publications on the search for substances that show inhibitory activity against SARS-CoV-2 infectivity, paying particular attention to the effect on different stages of the life cycle of the virus. REVIEW METHODS: The review was based on an analysis of the latest available scientific literature and international databases. The data collected relate to the years 2020-2021. BRIEF DESCRIPTION OF THE STATE OF KNOWLEDGE: Extremely intensive research is underway to find compounds that inhibit infection with the SARS-CoV-2 virus. Promising areas of research among the many current endeavours are antiviral compounds that stimulate the immune system, counter proliferation or affect individual viral replication cycles. These include, among others, interferons, monoclonal antibodies, natural compounds, peptides, aptamers, metal salts, and anti-inflammatory agents, inhibitors of viral enzymem, such as the RNA-dependent RNA polymerase. Preparations that help the body to combat the effects of infection have also assumed much importance. CONCLUSIONS: The ongoing research is focused on the development of new antiviral agents, as well as the use of the existing drugs on the market. The results of clinical trials are promising and give hope for the development of effective therapies against SARS-CoV-2 and emerging variants of this virus.

A new locality of the Haemaphysalis concinna tick (Koch, 1844) in Poland and its role as a potential vector of infectious diseases

The Haemaphysalis concinna tick is a rare species in Poland. To date, it was found only once a few decades ago. During tick collection for epidemiological studies, a stable population of this arachnid was found in a military training area near Nowa Deba. This report is particularly important, given the role of Haemaphysalis concinna in the spread of dangerous vector-borne diseases.

First molecular characterization of Dobrava-Belgrade virus found in Apodemus flavicollis in Poland.

INTRODUCTION: Dobrava-Belgrade virus (DOBV) is one of the emerging pathogens which have been reported during the last decades in Europe and have attracted the attention of researchers. The course of infection among humans may have a varied course - from the completely asymptomatic to the more severe forms, such as haemorrhagic fever with renal syndrome (HFRS). DOBV is hosted and carried by rodents like Apodemus flavicollis or A. agrarius, which occur commonly in Europe. OBJECTIVE: To-date, orthohantaviruses have been reported in Poland, both in humans and animals, but detailed country-scale studies have not yet been carried out. The aim of the study was molecular characterization of a strain which was found in A. flavicollis in south-eastern Poland. MATERIAL AND METHODS: The phylogenetic analysis of the first Dobrava-Belgrade virus found in A. flavicollis in the subcarpathian region of south-eastern Poland, presented in this study, was performed after virus proliferation in cell culture and sequencing of specific PCR products. RESULTS: Based on genetic sequences of fragments of three segments (S, M and L), the isolated virus was assigned to the Dobrava genotype, taking into consideration the most current classification of the DOBV species. CONCLUSIONS: The Dobrava-Belgrade virus strain isolated from A. flavicollis in the subcarpathian region of south-eastern Poland, has been molecularly characterized and assigned to Dobrava genotype, thereby the occurrence of that genotype in Poland has been confirmed by molecular techniques.

Utilisation of peptides against microbial infections - a review.

The emergence of resistance in microorganisms on a global scale has made it necessary to search for new antimicrobial factors. Antimicrobial peptides (AMPs) seem to meet these expectations. AMPs are produced by bacteria, viruses, plants, and animals, and may be considered as a new class of drugs intended for the prophylaxis and treatment of both systemic and topical infections. The aim of this study is to review the results of studies on the use of peptides to combat infections in vivo. Antimicrobial peptides may be applied topically and systemically. Among the peptides used topically, a very important area for their application is ophthalmology. AMPs in ophthalmology may be used mainly for the protection of contact lenses from ocular pathogens. Many AMPs are in clinical trials for application in the therapy of local infections. There may be mentioned such preparations as: pexiganan (magainin analogue), MX-226 (based on indolicidin), NEUPREX (isolated from human BPI (bactericidal/permeability-increasing) protein), IB-367 (variant of porcine protegrin), P113 (based on histatin), daptomycin, polymyxins, as well as peptidomimetics. In the combat against systemic infections are used such peptides as: P113D (modified P113 peptide containing D-amino acids), colistin, peptoids, and peptides containing non-typical amino acids or non-peptide elements. AMPs are also used as antiprotozoal, antifungal, antitoxic and immunostimulatory agents. The limitations in the use of peptides in the treatment of infections, such as susceptibility to proteolysis, and resistance of microorganisms to the peptides, are also discussed. AMPs are a promising strategy in the fight against microbial infections.

Serological surveillance of vector-borne and zoonotic diseases among hunters in eastern Poland.

BACKGROUND & OBJECTIVES: Many etiological agents of zoonoses are considered as significant biological hazard to people visiting forested areas frequently, for instance, hunters. They may be exposed to ticks, rodents, and birds as well as excreta/secretions of wild animals or contaminated water and soil. Hence, this population is at risk of contracting infection with pathogens such as Borrelia burgdorferi sensu lato (s.l.), Anaplasma phagocytophilum, Babesia spp., tick-borne encephalitis virus, Bartonella spp., Francisella tularensis, Echinococcus spp., or hantaviruses. The aim of the study was to assess the seroprevalence of zoonotic agents, viz. A. phagocytophilum, hantaviruses, and Echinococcus spp., with special regard to B. burgdorferi s.l., among hunters in Lubelskie Voivodeship (eastern Poland). METHODS: Serum samples collected from 134 hunters from Lubelskie Voivodeship were analyzed with the use of immunological techniques (enzyme-linked immunosorbent assay, line immunoblot test, and indirect fluorescence assay) for the presence of antibodies against the agents. RESULTS: Specific antibodies were detected in 66% of the tested individuals. Antibodies against B. burgdorferi s.l. (39%), A. phagocytophilum (30%), hantaviruses (9%), and Echinococcus spp. (8%) were detected individually or as mixed results. INTERPRETATION & CONCLUSION: The results confirm that there is a risk of exposure to different pathogens in the forested areas in eastern Poland and that hunters are highly vulnerable to infection with the examined zoonotic agents. A significant proportion of co-occurring antibodies against different pathogens was noticed. Thus, hunters have to take special care of their health status evaluation and mitigate the exposure risk by using adequate prophylaxis measures.

Biased sex ratio among worms of the family Heligmosomidae--searching for a mechanism.

According to Fisher's principle, an equal sex ratio is an evolutionary stable strategy. However, biased sex ratios have been reported in many metazoan parasite species, although the causes and mechanisms of the observed bias are still poorly understood. In the present study, we analysed sex ratios in long-term datasets from three populations of bank voles (Clethrionomys (=Myodes) glareolus) infected with Heligmosomum mixtum and Heligmosomoides glareoli. The overall sex ratios of both species were female-biased but in contrast to previous studies we did not find a relationship between the proportion of females and infection intensity. A higher female bias was observed in older hosts, suggesting that the sex ratio changes over time; the lifespan of nematodes in the family Heligmosomidae is known to be comparable with that of their hosts. We also compared the distributions of sexes in voles infected with two, three, four or five worms and we found significant differences from the expected values in both parasite species. In infections with four and five H. glareoli we observed more single-sex infections than expected, both female- and male-dominated, whereas in the case of H. mixtum female-dominated infections were more frequent.

Prevalence of Coxiella burnetii in environmental samples collected from cattle farms in Eastern and Central Poland (2011-2012).

Coxiella burnetii is the etiologic agent of Q fever. It may occur as two different morphological forms, a large cell variant (LCV) and a small cell variant (SCV). The SCV is characterized by unique resistance to physical and chemical factors and may survive in the environment for many months. The objective of this study was to examine environmental samples for the presence of C. burnetii using real-time PCR in areas where Q fever was previously reported and in randomly selected animal farms where Q fever was not reported. The samples were collected in the following provinces in Poland: Lublin, Subcarpathian and Masovian. Monitoring was performed with real-time PCR and serological methods. Of the 727 environmental samples, 33 (4.54%) contained the multi-copy insertion sequence IS1111, which is specific for C. burnetii. Subsequently, the presence of C. burnetii antibodies was determined using serological tests in selected herds in which positive genetic results were obtained. Serological analyses of 169 serum samples using CFT and ELISA were performed on Polish black-and-white Holstein-Friesian cows and one cow imported from Denmark. Using the CFT method, 11 samples were positive for phase I antibodies and six were positive for phase II antibodies. Moreover, in two cases, the presence of antibodies specific for both phase I and phase II antigens of C. burnetii was detected. However, of the 169 examined serum samples, 20 were positive by ELISA test, of which six were also positive by CFT. Additionally, multi spacer typing (MST) of isolated C. burnetii strains was performed. The MST results identified two new genotypes in Poland, ST3 and ST6. The results indicate that continued research regarding spread of this pathogen within a country is necessary.

Effect of isopropyl methylphosphonofluoridate (IMPF) poisoning on selected immunological parameters of angiogenesis.

INTRODUCTION AND OBJECTIVE: Acetylcholinesterase (AChE) and cholinergic receptors play an important role in the immune system, including lymphocyte-induced angiogenesis. However, their exact role is not fully understood. The presented work tests the influence of isopropyl methylphosphonofluoridate (IMPF), an irreversible inhibitor of AChE, on selected immune parameters associated with angiogenesis in mice. The levels of VEGF, bFGF, TNF-α, and IFN-γ production were measured, together with the ability of lymphoid spleen cells to induce local GvH reaction after a single dose of IMPF. MATERIALS AND METHOD: Experiments were performed in male BALB/c mice. Acetylcholinesterase activity in erythrocytes was determined by the Ellman`s procedure. Levels of cytokines were measured in serum using standard commercial ELISA kits. Influence of IMPF intoxication upon angiogenesis was examined by the LIA test, according to the Sidky and Auerbach procedure. RESULTS: The results showed a 6- and 8-fold increase in VEGF at days 1 and 7 of the experiment, respectively, as well as a decrease (at days 14 and 21 after administration), followed by a significant increase (day 1) in bFGF levels. A statistically significant decrease in the concentration of IFN-γ was observed throughout all experiments. The maximum decrease in the level of TNF-α was found at days 1 and 7 after administration of IMPF. Additionally, a significant decrease was found in the ability to form new blood vessels following IMPF administration. CONCLUSIONS: This study revealed that IMPF has a significant effect on the regulation of lymphocyte-induced angiogenesis, which is related with the modulation of angiogenic and pro-inflammatory cytokines secretion. The observed differences suggest a possible derangement of certain elements of the neuronal and/or non-neuronal cholinergic system.

Diversity of influenza-like illness etiology in Polish Armed Forces in influenza epidemic season.

The aim of this study was to conduct an epidemiological and laboratory surveillance of Influenza-Like Illnesses (ILI) in Polish Armed Forces, civilian military personnel and their families in 2011/2012 epidemic season, under the United States Department of Defense-Global Emerging Infections Surveillance and Response System (DoD-GEIS). ILI incidence data were analyzed in relation to age, gender, patient category as well as pathogen patterns. Multiple viral, bacterial and viral-bacterial co-infections were identified. Nose and throat swabs of active duty soldiers in the homeland country and in the NATO peacekeeping forces KFOR (Kosovo Force), as well as members of their families were tested for the presence of viral and bacterial pathogens. From October 2011 to May 2012, 416 specimens from ILI symptoms patients were collected and analyzed for the presence of viral and bacterial pathogens. Among viruses, coronavirus was the most commonly detected. In the case of bacterial infections, the most common pathogen was Staphylococcus aureus.

Surveillance of hantaviruses in Poland: a study of animal reservoirs and human hantavirus disease in Subcarpathia.

The first cluster of hemorrhagic fever with renal syndrome (HFRS) in Poland was identified in 2007 in the Subcarpathian region. The natural environment of this area is a key habitat for hantavirus vectors. The animal reservoir of existing human HFRS clusters was studied to assess the occurrence of viruses (including Tula virus, Puumala virus, and Dobrava-Belgrade virus) among rodents. We examined 70 suspected human cases with symptoms corresponding to the clinical picture of HFRS. Serological analysis (indirect immunofluorescence assay and immunoblot) confirmed the presence of anti-hantavirus antibodies in 18 patients, which were surveyed with regard to developed symptoms and presumed rodent contact. Seroepidemiological analysis of newly confirmed human cases was performed, putative areas of human exposure were studied, and 194 rodents were subsequently captured from identified areas. Internal organs (lungs, heart, spleen, bladder, and kidneys) were collected from 64 Apodemus flavicollis, 55 Apodemus agrarius, 40 Myodes glareolus, 21 Mus musculus, and 14 Microtus arvalis and tested for the presence of hantavirus RNA by reverse transcription and subsequent real-time PCR. Positive samples were also tested by indirect immunofluorescence. Animal reservoir surveillance enabled the first detection of Puumala virus and Dobrava-Belgrade virus among animals in Poland. Furthermore, some places where rodents were captured correlated with areas of residence of laboratory-confirmed human cases and likely detected virus species. Moreover, three species of hantaviruses coexisting in a relatively small area were identified.

Review of methods used for identification of biothreat agents in environmental protection and human health aspects.

Modern threats of bioterrorism force the need to develop methods for rapid and accurate identification of dangerous biological agents. Currently, there are many types of methods used in this field of studies that are based on immunological or genetic techniques, or constitute a combination of both methods (immuno-genetic). There are also methods that have been developed on the basis of physical and chemical properties of the analytes. Each group of these analytical assays can be further divided into conventional methods (e.g. simple antigen-antibody reactions, classical PCR, real-time PCR), and modern technologies (e.g. microarray technology, aptamers, phosphors, etc.). Nanodiagnostics constitute another group of methods that utilize the objects at a nanoscale (below 100 nm). There are also integrated and automated diagnostic systems, which combine different methods and allow simultaneous sampling, extraction of genetic material and detection and identification of the analyte using genetic, as well as immunological techniques.

Acute respiratory distress syndrome (ARDS) in the course of influenza A/H1N1v infection--genetic aspects.

Influenza is a contagious respiratory disease caused by viruses belonging to the family Ortomyxoviridae. Among the influenza viruses type A, B and C, the A type virus shows the most pathogenic potential. Its surface receptor glycoproteins, hemagglutinin (HA) and neuraminidase (NA), are characterized by high antigenic variation, thus a host organism cannot develop permanent resistance. The case is described of a male patient with severe acute respiratory distress syndrome in the course of influenza A/N1H1v infection, confirmed by virological molecular analysis. During diagnostic procedures based on the MSSCP genotyping it was observed that the WHO recommended RT-PCR kits and/or procedure of sample collection from patients for molecular investigation could lead to false positive A/H1N1 pandemic strain detection because of the co-amplification during the RT-PCR fragments of the human genome.

Severe influenza outbreak in Western Ukraine in 2009--a molecular-epidemiological study.

INTRODUCTION: In the autumn of 2009 the authors participated in a humanitarian operation in Western Ukraine by undertaking an epidemiological investigation of an influenza-like-illness (ILI) in the L'viv Oblast region. Mobile biological survey teams took samples from civilian patients with severe acute respiratory distress syndrome, rapid transportation of the samples, and their molecular analysis in Poland to provide accurate results. OBJECTIVE: The aim of the study was the molecular and epidemiological analysis of the biological samples collected. MATERIAL AND METHODS: Real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR), multiplex PCR techniques, traditional Sanger Sequencing and classical viral culture methods were used. RESULTS: Among the 124 influenza-like illness cases, ~50% (58) were positive for influenza A virus in WHO-CDC molecular assay, including subtyping. The specimens were further analyzed to confirm results and determine the genetic sequence. Phylogenetically, the nucleotide similarity of both the Ukraine specimens and reference A/California/7/2009 (pH1N1) was 99.2-99.3%. Oseltamivir resistance was not registered. HA1 region characterization showed an overall protein identity of 98.5-99.4%. CONCLUSIONS: An unexpected high contribution of influenza A was confirmed among ILI patients, as well as a very limited number of other detected viruses, indicate that the 2009 epidemic in western Ukraine was strongly related to novel influenza A/H1N1. The importance of swift sharing of information and reference laboratories networking in surveillance, as well as serving governments and international agencies in pursuing adequate actions, should be stressed.

Determination of melatonin and its precursors and metabolites using capillary electrophoresis with UV and fluorometric detection.

A micellar electrokinetic chromatography method has been developed for simultaneous determination of melatonin and its precursors and metabolites. A 20 mM borate buffer pH 9.5 with 50 mM SDS served as the electrolyte. Tryptophan, 5-methoxyindoleacetic acid, 6-hydroxymelatonin, melatonin, serotonin, and 5-methoxytryptamine were baseline separated in less than 13 min. The limits of detection for UV detection and fluorometric detection based on native fluorescence of analytes were at the sub-ppm level. The proposed method with UV detection was applied to melatonin content control in pharmaceutical tablets with a precision expressed as RSD (n = 7) = 1.6%. For biological samples extraction with chloroform and ethyl acetate was examined. With ethyl acetate and chloroform recoveries of 87.2% and 82.1% melatonin, respectively, were obtained from plasma samples. The recovery of melatonin from spiked urine samples was 80.0% for ethyl acetate and 82.5% for chloroform. Fluorometric detection provides about two-fold improvement over UV in the detection of melatonin and minor improvements for three other analytes, but is much poorer than UV for tryptophan and 6-hydroxymelatonin in applied conditions.

Post-traumatic plasminogenesis in intraarticular exudate in the knee joint.

BACKGROUND: Intraarticular exudate, observed in the knee joint a few weeks after a traumatic incident, is one of post-traumatic complications. Evacuation of the exudate prevents damage of the articular cartilage by the fluid possessing potent proteolytic properties. In view of the lack of data concerning the role of the fibrinolysis system in proteolytic destructive processes induced by the exudate, the aim of the study was to find out whether plasmin is present in the post-traumatic intraarticular exudate and whether it is generated in connection with excessive plasminogen activator levels or deficiency of plasminogen activator inhibitors in the synovial fluid. MATERIAL/METHODS: 55 patients (mean age 35.1), with history of knee joint traumas and exudate appearing in the joint at least 3 weeks post-traumatically. The patients and 30 healthy controls were subjected to the following tests of the synovial fluid and plasma: the levels of tissue plasminogen activator, type 1 plasminogen activator inhibitor, plasmin-alpha 2-antiplasmin complexes, fibrinogen and von Willebrand factor antigen, the activity of urokinase plasminogen activator, prekallikrein, alpha-2-antiplasmin, C1 inhibitor, type 1 plasminogen activator inhibitor, euglobulin clot lysis time. RESULTS: The patients' plasma demonstrated significantly higher levels of fibrinogen and PAP complexes, and decreased u-PA activity in comparison in that obtained from the controls. Significantly higher levels of PAP complexes and u-PA antigen were found in the exudate than in the patients' plasma. CONCLUSIONS: Local, intraarticular plasmin generation, probably u-PA-dependent, occurs in knee joint exudate. Plasminogen activator inhibitors are probably not very closely associated with increased intraarticular plasminogenesis.