COVID-19: unravelling the clinical progression of nature's virtually perfect biological weapon

Venous Thrombosis in Airborne Viral Infections: Is Coronavirus Disease 2019 now Any Different from Influenza?

One of the hallmarks of coronavirus disease 2019 (COVID-19), particularly in complicated cases (i.e., requiring hospitalization or intensive care support), is persistent hemostasis activation, which may be associated with a vast array of thrombotic episodes involving both the arterial and venous systems. The renewed emphasis on the relationship between viral infections and venous thrombosis paves the way for determining whether a more common and often underestimated infection disease, such as influenza, may also be associated with a significant burden of venous thrombotic episodes, and how this eventual thrombotic risk compares to that seen in COVID-19, both in the past and with newer variants. Our review of studies comparing the burden of venous thromboembolism (VTE) in patients with COVID-19 or influenza revealed that the thrombotic risk appears to be significantly higher in patients with COVID-19 but remains certainly not meaningless in those with influenza, particularly in subjects infected by highly virulent strains (i.e., H1N1), in those who develop pneumonia and require intensive care support. In these specific clinical settings, the adoption of tailored thromboprophylaxis may be indicated though more studies are compellingly needed on this matter. As COVID-19 variants emerge, there is a possibility that the VTE burden of COVID-19 will decrease, and progress to that of other respiratory viruses.

The Effect of Physiotherapy on Dyspnea, Muscle Strength and Functional Status in Patients with Long COVID Syndrome

BACKGROUND

Patients who were infected with COVID-19 may experience Long COVID syndrome. We examined the effectiveness of physiotherapy on dyspnea, muscle strength, and functional status in Long COVID syndrome.

METHODS

The exercise group underwent an 8-week supervised physiotherapeutic program consisting of interval aerobic exercise and strengthening exercises, each lasting 30 min. The control group did not engage in any exercise. Dyspnea, muscle strength, and functional status were assessed at the beginning and end of the intervention in both groups.

RESULTS

No significant baseline differences were found between the two groups. The exercise group demonstrated improvements compared to baseline in dyspnea, quadriceps muscle strength, and functional status. Specifically, there was a significant increase of 3.7 lifts in the 60-s sit-to-stand test (p = 0.01), an increase of 5.86 kg in right quadriceps muscle strength (p = 0.03), an increase of 8.26 kg in left quadriceps muscle strength (p = 0.01), and a decrease in dyspnea score by 0.95 points (p = 0.02).

CONCLUSIONS

Similar studies have reported improvements in dyspnea, muscle strength, and functional status in the exercise group. However, further research with larger sample sizes is needed to confirm these findings.

Effects of Recombinant SARS-CoV-2 Spike Protein Variants on Platelet Morphology and Activation

Platelets are central elements of hemostasis and also play a pivotal role in the pathogenesis of thrombosis in coronavirus disease 2019. This study was planned to investigate the effects of different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) recombinant spike protein variants on platelet morphology and activation. Citrated whole blood collected from ostensibly healthy subjects was challenged with saline (control sample) and with 2 and 20 ng/mL final concentration of SARS-CoV-2 recombinant spike protein of Ancestral, Alpha, Delta, and Omicron variants. Platelet count was found to be decreased with all SARS-CoV-2 recombinant spike protein variants and concentrations tested, achieving the lowest values with 20 ng/mL Delta recombinant spike protein. The mean platelet volume increased in all samples irrespective of SARS-CoV-2 recombinant spike protein variants and concentrations tested, but especially using Delta and Alpha recombinant spike proteins. The values of both platelet function analyzer-200 collagen-adenosine diphosphate and collagen-epinephrine increased in all samples irrespective of SARS-CoV-2 recombinant spike protein variants and concentrations tested, and thus reflecting platelet exhaustion, and displaying again higher increases with Delta and Alpha recombinant spike proteins. Most samples where SARS-CoV-2 recombinant spike proteins were added were flagged as containing platelet clumps. Morphological analysis revealed the presence of a considerable number of activated platelets, platelet clumps, platelet-monocyte, and platelet-neutrophils aggregates, especially in samples spiked with Alpha and Delta recombinant spike proteins at 20 ng/mL. These results provide support to the evidence that SARS-CoV-2 is capable of activating platelets through its spike protein, though such effect varies depending on different spike protein variants.

Role of epinephrine in attenuating cytokine storm, decreasing ferritin, and inhibiting ferroptosis in SARS-CoV-2

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for coronavirus disease 2019. It presents one of the most threatening pandemics in the history of humanity. The mortality and morbidity represent an unprecedented challenge to the modern medical era. SARS-CoV-2 results in acute respiratory distress syndrome, high concentrations of proinflammatory mediators, cytokine storm (CS) due to massive release of cytokines, hypercoagulation, and hemoglobin disintegration. Dysregulation of iron homeostasis, iron overload as indicated by high ferritin level, and ferroptosis are major factors in the pathogenesis of the disease. We report a case of SARS-CoV-2 in which the use of epinephrine (Epi) resulted in an unexpected attenuation of CS, decreasing ferritin level and inhibiting ferroptosis.

CASE PRESENTATION

A 64-year-old male patient with a history of multiple medical comorbidities had been diagnosed with SARS-CoV-2. Further evaluation showed marked increase in inflammatory markers, severe hyperferritinemia, and lymphopenia in laboratory blood tests. The characteristic score of CS was strongly positive, and in addition to regular treatment, the patient received Epi due to development of acute generalized skin rash, severe itching, and edema of lips and tongue. Epi may have successfully terminated not only the acute cutaneous condition, but also have attenuated CS, decreased ferritin level, and other inflammatory markers in addition to complete patient's recovery.

CONCLUSION

Epinephrine may attenuate CS and inhibit ferroptosis which is an iron-dependent, non-apoptotic mode of cell death. Epi interacts with ferric and/or ferrous iron and built a stable complex that impedes activation of beta-adrenergic receptors. Epi may cause marked decrease of ferritin and other inflammatory markers. Epi may be used to decrease iron overload which is associated with many medical diseases like type 2 diabetes mellitus and cardiometabolic diseases such as coronary heart disease and cerebrovascular disease. As a new clinical indication extensive studies are required for further assessment and possible therapeutic uses.

The association of hematological inflammatory markers and psychological function in COVID-19 patients: A cross-sectional study

Mental health disorders are linked to systemic inflammation. Due to high inflammation and mental health disorders in COVID-19 patients, we aimed to investigate the relationship between blood inflammatory markers such as red cell distribution width to platelet ratio (RPR), platelet-lymphocyte ratio (PLR), neutrophil/lymphocyte ratio (NLR), red cell distribution width (RDW), white blood cell (WBC), and psychological function in COVID-19 patients. In the current cross-sectional study, neuro-psychological function, and a complete blood count (CBC) were measured on 120 COVID-19 patients aged >30 years from the Imam Reza Hospital in Mashhad, Iran. Our results showed that anxiety related to MCHC (mean ± SD: 32.71 ± 1.68, p < 0.05), WBC (mean ± SD: 12.23 ± 5.43, p < 0.05), and PLR (median (IQR): 28.72 (15.88-41.31), p < 0.05) significantly. In the stress subgroup, only RPR was associated with stress (p < 0.05). Linear regression between hematological parameters and psychological score indicated that RDW and PLR had a significantly positive association with depression (β = 0.086; p = 0.045 and β = 1.326; p = 0.016, respectively) and anxiety scores (β = 0.100; p = 0.038 and β = 1.356; p = 0.010, respectively). Moreover, a positive correlation was found between PLR and stress (β = 1.102; p = 0.012). This study showed a positive association between depression/anxiety/stress symptoms and levels of hematological inflammatory markers including PLR and RDW. The findings of this study provide novel insights into mental health and physiological markers, underscoring the potential influence of inflammation on mood disorders. Our findings offer exciting prospects for future research and may lead to innovative approaches in the management and treatment of depression, anxiety, and stress.

Assessment of humoral and cellular immunity after bivalent BNT162b2 vaccination and potential association with reactogenicity

OBJECTIVES

This study investigated the feasibility and clinical value of using a novel, automated and high-throughput SARS-CoV-2 Interferon Gamma Release Assay (IGRA), combined with total anti-SARS-CoV-2 antibodies assessment, for evaluating the immune response after bivalent BNT162b2 vaccination.

METHODS

A cohort of healthcare workers, who already underwent primary vaccination and boosting with monovalent BNT162b2 vaccine, received a booster dose of the new BNT162b2 bivalent formulation. Blood samples were taken immediately before vaccination (T0) and 1 month afterwards (T1). Humoral and cellular immunity were assayed with Roche Elecsys Anti-SARS-CoV-2 and Roche Elecsys IGRA SARS-CoV-2, respectively.

RESULTS

The study population consisted of 51 subjects (median age: 43 years; 51% females). Total anti-SARS-CoV-2 antibodies and IGRA SARS-CoV-2 values increased at T1 from 9,050 to 25,000 BAU/mL (p<0.001), and from 0.44 to 0.78 IU/mL (p=0.385), accounting for median increase of 2.0 and 1.6 folds, respectively. Increased T1 values of total anti-SARS-CoV-2 antibodies and IGRA SARS-CoV-2 were recorded in 100% and 68.6% subjects, respectively. In those with baseline values below the median, post-vaccine levels displayed larger increases of 3.3 and 5.1 folds for anti-SARS-CoV-2 total antibodies and IGRA SARS-CoV-2, respectively. The variation of total anti-SARS-CoV-2 antibodies was inversely associated with their T0 values (r=-0.97; p<0.001), whilst that of IGRA SARS-CoV-2 was inversely associated with its T0 value (r=-0.58; p<0.001). No other signifcant associations were found with demographical or clinical variables, including side effects.

CONCLUSIONS

The bivalent BNT162b2 vaccine booster enhances humoral and cellular immunity against SARS-CoV-2, especially in recipients with lower baseline biological protection.

Prime-Pull Immunization of Mice with a BcfA-Adjuvanted Vaccine Elicits Sustained Mucosal Immunity That Prevents SARS-CoV-2 Infection and Pathology

Vaccines against SARS-CoV-2 that induce mucosal immunity capable of preventing infection and disease remain urgently needed. In this study, we demonstrate the efficacy of Bordetella colonization factor A (BcfA), a novel bacteria-derived protein adjuvant, in SARS-CoV-2 spike-based prime-pull immunizations. We show that i.m. priming of mice with an aluminum hydroxide- and BcfA-adjuvanted spike subunit vaccine, followed by a BcfA-adjuvanted mucosal booster, generated Th17-polarized CD4+ tissue-resident memory T cells and neutralizing Abs. Immunization with this heterologous vaccine prevented weight loss following challenge with mouse-adapted SARS-CoV-2 (MA10) and reduced viral replication in the respiratory tract. Histopathology showed a strong leukocyte and polymorphonuclear cell infiltrate without epithelial damage in mice immunized with BcfA-containing vaccines. Importantly, neutralizing Abs and tissue-resident memory T cells were maintained until 3 mo postbooster. Viral load in the nose of mice challenged with the MA10 virus at this time point was significantly reduced compared with naive challenged mice and mice immunized with an aluminum hydroxide-adjuvanted vaccine. We show that vaccines adjuvanted with alum and BcfA, delivered through a heterologous prime-pull regimen, provide sustained protection against SARS-CoV-2 infection.

Regulation of Epithelial Sodium Transport by SARS-CoV-2 Is Closely Related with Fibrinolytic System-Associated Proteins

Dyspnea and progressive hypoxemia are the main clinical features of patients with coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pulmonary pathology shows diffuse alveolar damage with edema, hemorrhage, and the deposition of fibrinogens in the alveolar space, which are consistent with the Berlin Acute Respiratory Distress Syndrome Criteria. The epithelial sodium channel (ENaC) is a key channel protein in alveolar ion transport and the rate-limiting step for pulmonary edema fluid clearance, the dysregulation of which is associated with acute lung injury/acute respiratory distress syndrome. The main protein of the fibrinolysis system, plasmin, can bind to the furin site of γ-ENaC and induce it to an activation state, facilitating pulmonary fluid reabsorption. Intriguingly, the unique feature of SARS-CoV-2 from other β-coronaviruses is that the spike protein of the former has the same furin site (RRAR) with ENaC, suggesting that a potential competition exists between SARS-CoV-2 and ENaC for the cleavage by plasmin. Extensive pulmonary microthrombosis caused by disorders of the coagulation and fibrinolysis system has also been seen in COVID-19 patients. To some extent, high plasmin (ogen) is a common risk factor for SARS-CoV-2 infection since an increased cleavage by plasmin accelerates virus invasion. This review elaborates on the closely related relationship between SARS-CoV-2 and ENaC for fibrinolysis system-related proteins, aiming to clarify the regulation of ENaC under SARS-CoV-2 infection and provide a novel reference for the treatment of COVID-19 from the view of sodium transport regulation in the lung epithelium.

Clinical utility of haematological inflammatory biomarkers in predicting 30-day mortality in hospitalised adult patients with COVID-19

Coronavirus disease 2019 (COVID-19) is a multisystem disease affecting respiratory, cardiovascular, gastrointestinal, neurological, immunological and haematological systems. The most important indices that have been studied are platelet (PLT) indices in addition to the PLT count and red blood cell distribution width (RDW). This retrospective study included 95 patients with COVID-19 and was conducted at the Hospital Isolation, Scientific and Medical Research Centre and Clinical Pathology Department at Zagazig University Hospitals, Egypt over 6 months from March to August 2021. All patients on admission had a full blood count, which included white blood cell (WBC) count, haemoglobin, RDW, PLT count and its indices in addition to PLT-to-WBC ratio (PWR) and PLT-to-lymphocyte ratio (PLR), which were calculated for all the study patients. There were significant linear correlations for higher levels of the PLR, PWR and RDW and mortality rate (p = 0.03, p < 0.001 and p < 0.001 respectively). Moreover, on multivariable analysis the RDW, PLT count and PWR levels were independent prognostic predictors for mortality with a hazard ratio [HR] of 1.25 (95% confidence interval [CI] 1.09-1.44, p = 0.002), 1.00 (95% CI 0.99-1.00, p = 0.03) and 2.3 (95% CI 1.21-4.48, p = 0.01) respectively. The RDW and PLT indices are accessible predictors that can be valuable prognostic factors for survival assessment and risk stratification of COVID-19.

What We Know (and Do not Know) Regarding the Pathogenesis of Pulmonary Thrombosis in COVID-19

The clinical course of coronavirus disease 2019 (COVID-19) is often complicated by the onset of venous thrombosis and thromboembolism (VTE), encompassing also pulmonary thrombosis. Recent statistics attests that the cumulative frequency of VTE can be as high as 30% in COVID-19 hospitalized patients, increasing to nearly 40 to 70% (depending on systematic screening) in those with severe illness, mechanical ventilation, or intensive care unit admission. The risk of venous thrombosis seems mostly limited to the active phase of disease, and is directly associated with some genetic (i.e., inherited prothrombotic predisposition) and demographical factors (male sex, overweight/obesity), disease severity (risk increasing progressively from hospitalization to development of severe illness, being the highest in patients needing mechanical ventilation and/or intensive care), presence and extent of pulmonary disease, coexistence of multiple risk factors (immobilization, mechanical ventilation, co- or superinfections), along with increased values of inflammatory and thrombotic biomarkers. At least three different phenotypes of pulmonary thrombosis may develop in COVID-19 patients, one caused by typical embolization from peripheral venous thrombosis (e.g., deep vein thrombosis), a second type triggered by local inflammation of nearby pulmonary tissue, and a third one mostly attributable to the prothrombotic state consequent to the pronounced systemic inflammatory response (i.e., the so-called cytokine storm) that is frequently observed in COVID-19. Although the pathogenesis of these three conditions has different features, their discrimination is essential for diagnostic and therapeutic purposes. The prognosis of COVID-19 patients who develop pulmonary thrombosis is also considerably worse than those who do not, thus probably needing frequent monitoring and more aggressive therapeutic management.

COVID-19 and pregnancy: clinical outcomes; mechanisms, and vaccine efficacy

As the COVID-19 pandemic continues into its third year, emerging data indicates increased risks associated with SARS-CoV-2 infection during pregnancy, including pre-eclampsia, intrauterine growth restriction, preterm birth, stillbirth, and risk of developmental defects in neonates. Here, we review clinical reports to date that address different COVID-19 pregnancy complications. We also document placental pathologies induced by SARS-CoV-2 infection, entry mechanisms in placental cells, and immune responses at the maternal-fetal interface. Since new variants of SARS-CoV-2 are emerging with characteristics of higher transmissibility and more effective immune escape strategies, we also briefly highlight the genomic and proteomic features of SARS-CoV-2 investigated to date. Vector and mRNA-based COVID-19 vaccines continue to be rolled out globally. However, because pregnant individuals were not included in the vaccine clinical trials, some pregnant individuals have safety concerns and are hesitant to take these vaccines. We describe the recent studies that have addressed the effectiveness and safety of the current vaccines during pregnancy. This review also sheds light on important areas that need to be carefully or more fully considered with respect to understanding SARS-CoV-2 disease mechanisms of concern during pregnancy.

Antiviral activity of amiodarone in SARS-CoV-2 disease

Amiodarone seems to exhibit some antiviral activity in the disease caused by SARS-CoV-2. Here we have examined the SARS-CoV-2 disease course in the entire population of the Czech Republic and compared it with the course of the disease in patients treated with amiodarone in two major Prague’s hospitals. In the whole population of the Czech Republic SARS-CoV-2 infected 1665070 persons (15.6 %) out of 10694000 (100 %) between 1 April 2020 and 30 June 2021. In the same time period only 35 patients (3.4 %) treated with amiodarone were infected with SARS-CoV-2 virus out of 1032 patients (100 %) who received amiodarone. It appears that amiodarone can prevent SARS-CoV-2 virus infection by multiple mechanisms. In in-vitro experiments it exhibits SARS-CoV-2 virus replication inhibitions. Due to its anti-inflammatory and antioxidant properties, it may have beneficial effect on the complications caused by SARS-CoV-2 as well. Additionally, inorganic iodine released from amiodarone can be converted to hypoiodite (IO-), which has antiviral and antibacterial activity, and thus can affect the life cycle of the virus.

Antiviral activity of amiodarone in SARS-CoV-2 disease

Amiodarone seems to exhibit some antiviral activity in the disease caused by SARS-CoV-2. Here we have examined the SARS-CoV-2 disease course in the entire population of the Czech Republic and compared it with the course of the disease in patients treated with amiodarone in two major Prague's hospitals. In the whole population of the Czech Republic SARS-CoV-2 infected 1665070 persons (15.6 %) out of 10694000 (100 %) between 1 April 2020 and 30 June 2021. In the same time period only 35 patients (3.4 %) treated with amiodarone were infected with SARS-CoV-2 virus out of 1032 patients (100 %) who received amiodarone. It appears that amiodarone can prevent SARS-CoV-2 virus infection by multiple mechanisms. In in-vitro experiments it exhibits SARS-CoV-2 virus replication inhibitions. Due to its anti-inflammatory and antioxidant properties, it may have beneficial effect on the complications caused by SARS-CoV-2 as well. Additionally, inorganic iodine released from amiodarone can be converted to hypoiodite (IO-), which has antiviral and antibacterial activity, and thus can affect the life cycle of the virus.

High Plasma Levels of Activated Factor VII-Antithrombin Complex Point to Increased Tissue Factor Expression in Patients with SARS-CoV-2 Pneumonia: A Potential Link with COVID-19 Prothrombotic Diathesis

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causal agent of coronavirus disease 2019 (COVID-19), in which coagulation abnormalities and endothelial dysfunction play a key pathogenic role. Tissue factor (TF) expression is triggered by endothelial dysfunction. Activated factor VII-antithrombin (FVIIa-AT) complex reflects indirectly FVIIa-TF interaction and has been proposed as a potential biomarker of prothrombotic diathesis. FVIIa-AT plasma concentration was measured in 40 patients (30 males and 10 females; 64.8 ± 12.3 years) admitted with SARS-CoV-2 pneumonia during the first pandemic wave in Italy. Two sex- and age-matched cohorts without COVID-19, with or without signs of systemic inflammation, were used to compare FVIIa-AT data. The FVIIa-AT plasma levels in COVID-19 patients were higher than those in non-COVID-19 subjects, either with or without inflammation, while no difference was observed among non-COVID-19 subjects. The association between COVID-19 and FVIIa-AT levels remained significant after adjustment for sex, age, C-reactive protein, renal function, fibrinogen, prothrombin time and activated partial thromboplastin time. Our results indicate that SARS-CoV-2 infection, at least during the first pandemic wave, was characterized by high FVIIa-AT levels, which may suggest an enhanced FVIIa-TF interaction in COVID-19, potentially consistent with SARS-CoV-2-induced endotheliopathy.

Pregnancy and COVID-19

Evidence indicates that SARS-CoV-2 infection increases the likelihood of adverse pregnancy outcomes. Modifications in the circulatory, pulmonary, hormonal, and immunological pathways induced by pregnancy render pregnant women as a high-risk group. A growing body of research shows that SARS-CoV-2 infection during pregnancy is connected to a number of maternal complications, including pneumonia and intensive care unit (ICU) hospitalization. Miscarriages, stillbirth, preterm labor, as well as pre-eclampsia and intrauterine growth restriction are also among the most often documented fetal implications, particularly among expecting women who have significant COVID-19 symptoms, often affecting the timing and route of delivery. Thus, prevention of infection and pharmacological treatment options should aim to minimize the aforementioned risks and ameliorate maternal, obstetric and fetal/neonatal outcomes.

The association between macrovascular complications and intensive care admission, invasive mechanical ventilation, and mortality in people with diabetes hospitalized for coronavirus disease-2019 (COVID-19)

BACKGROUND

It is not clear whether pre-existing macrovascular complications (ischemic heart disease, stroke or peripheral artery disease) are associated with health outcomes in people with diabetes mellitus hospitalized for COVID-19.

METHODS

We conducted cohort studies of adults with pre-existing diabetes hospitalized for COVID-19 infection in the UK, France, and Spain during the early phase of the pandemic (between March 2020-October 2020). Logistic regression models adjusted for demographic factors and other comorbidities were used to determine associations between previous macrovascular disease and relevant clinical outcomes: mortality, intensive care unit (ICU) admission and use of invasive mechanical ventilation (IMV) during the hospitalization. Output from individual logistic regression models for each cohort was combined in a meta-analysis.

RESULTS

Complete data were available for 4,106 (60.4%) individuals. Of these, 1,652 (40.2%) had any prior macrovascular disease of whom 28.5% of patients died. Mortality was higher for people with compared to those without previous macrovascular disease (37.7% vs 22.4%). The combined crude odds ratio (OR) for previous macrovascular disease and mortality for all four cohorts was 2.12 (95% CI 1.83-2.45 with an I² of 60%, reduced after adjustments for age, sex, type of diabetes, hypertension, microvascular disease, ethnicity, and BMI to adjusted OR 1.53 [95% CI 1.29-1.81]) for the three cohorts. Further analysis revealed that ischemic heart disease and cerebrovascular disease were the main contributors of adverse outcomes. However, proportions of people admitted to ICU (adjOR 0.48 [95% CI 0.31-0.75], I² 60%) and the use of IMV during hospitalization (adjOR 0.52 [95% CI 0.40-0.68], I² 37%) were significantly lower for people with previous macrovascular disease.

CONCLUSIONS

This large multinational study of people with diabetes mellitus hospitalized for COVID-19 demonstrates that previous macrovascular disease is associated with higher mortality and lower proportions admitted to ICU and treated with IMV during hospitalization suggesting selective admission criteria. Our findings highlight the importance correctly assess the prognosis and intensive monitoring in this high-risk group of patients and emphasize the need to design specific public health programs aimed to prevent SARS-CoV-2 infection in this subgroup.

A Quantitative ELISA to Detect Anti-SARS-CoV-2 Spike IgG Antibodies in Infected Patients and Vaccinated Individuals

There is an ongoing need for high-precision serological assays for the quantitation of anti-SARS-CoV-2 antibodies. Here, a trimeric SARS-CoV-2 spike (S) protein was used to develop an ELISA to quantify specific IgG antibodies present in serum, plasma, and dried blood spots (DBS) collected from infected patients or vaccine recipients. The quantitative S-ELISA was calibrated with international anti-SARS-CoV-2 immunoglobulin standards to provide test results in binding antibody units per mL (BAU/mL). The assay showed excellent linearity, precision, and accuracy. A sensitivity of 100% was shown for samples collected from 54 patients with confirmed SARS-CoV-2 infection more than 14 days after symptom onset or disease confirmation by RT-PCR and 58 vaccine recipients more than 14 days after vaccination. The assay specificity was 98.3%. Furthermore, antibody responses were measured in follow-up samples from vaccine recipients and infected patients. Most mRNA vaccine recipients had a similar response, with antibody generation starting 2-3 weeks after the first vaccination and maintaining positive for at least six months after a second vaccination. For most infected patients, the antibody titers increased during the second week after PCR confirmation. This S-ELISA can be used to quantify the seroprevalence of SARS-CoV-2 in the population exposed to the virus or vaccinated.

The Global Impact of COVID-19 on Threat Appraisals

We planned an infodemiological analysis to estimate the global impact of coronavirus disease 2019 (COVID-19) on threat appraisals. We accessed Google Trends using the search terms “Anxiety”, “Distress”, “Fear”, “Rumination”, “Stress” and “Worry” within the “topic” domain, setting the geographical location to “worldwide”, between July 2017 and July 2022. The weekly Google Trends score for the six search terms, thus, mirroring Web popularity and probable prevalence, was compared between the two search periods, “pre-COVID” (between July 2017 and February 2020) and COVID (between March 2020 and July 2022), thus, reflecting the volume of searches before and during the ongoing COVID-19 pandemic. The median weekly Google Trends score of all these search terms significantly increased during the COVID-19 pandemic, i.e., anxiety by 22%, distress by 13%, fear by 9%, rumination by 18%, stress by 13% and worry by 20%. With variable strength, the weekly Google Trends scores of each search term were found to be significantly associated (all p < 0.001). We can, hence, conclude that the enhanced burden of threat appraisals observed after SARS-CoV-2 spread leads the way to establish preventive, diagnostic and therapeutic measures in order to limit the unfavorable mental health consequences caused by the ongoing COVID-19 pandemic.

Serum Antibodies SARS-CoV-2 Spike (S) Protein Receptor-Binding Domain in OBGYN Residents and Effectiveness 3 Months after COVID-19 Vaccination

BACKGROUND: The health care workers are considered as vulnerable people who had higher infecting dose of SARS-CoV-2 infection compared to other society. Among more than 500 deaths of Indonesians physicians, obstetrics and gynecologist (OBGYN) has become the most specialists who died in this pandemic. AIM: The objective of our study is to evaluate the antibodies of SARS-CoV-2 in serum OBGYN residents post-vaccination as well as the presence of infection 3 months after the vaccination. METHODS: A prospective cohort study was conducted in OBGYN residents Universitas Indonesia. Serum antibodies SARS-CoV-2 spike (S) protein receptor-binding domain (RBD) was measured using electrochemiluminescence immunoassay, 21 days after Sinovac vaccination, with basic characteristics being recorded. Within 3 months follow-up, the participants were monthly checked related to post-vaccination infection. RESULTS: The median antibodies SARS-CoV-2 for all participants were 50.72 (19.09–98.57) U/mL. There were 20 residents (24.1%) who had post-vaccination infection within 3 months and dominated by asymptomatic to mild symptoms. Body mass index (r = –0.221, p = 0.044) and sleep hours (r = –0.225, p = 0.041) were found to be inversely correlated with antibodies SARS-CoV-2 S RBD. CONCLUSION: Antibodies SARS-CoV-2 S RBD found to be correlated with BMI and sleep hours. The 3-month post-vaccine infection among OBGYN residents was almost similar to Jakarta’s positivity rate and the efficacy rate was higher than expected by National Agency of Drug and Food Control.

D-dimers-"Normal" Levels versus Elevated Levels Due to a Range of Conditions, Including "D-dimeritis," Inflammation, Thromboembolism, Disseminated Intravascular Coagulation, and COVID-19

D-dimers reflect a breakdown product of fibrin. The current narrative review outlines how D-dimers can arise in normal individuals, as well as in patients suffering from a wide range of disease states. D-dimers in normal individuals without evident thrombosis can arise from background fibrinolytic activity in various tissues, including kidney, mammary and salivary glands, which ensures smooth flow of arising fluids where any blood contamination could be immediately lysed. In addition, healthy individuals can also regularly sustain minor injuries, often unbeknown to them, and wound healing follows clot formation in these situations. D-dimers can also arise in anxiety and following exercise, and are also markers of inflammation. Lung inflammation (triggered by microbes or foreign particles) is perhaps also particularly relevant, since the hemostasis system and fibrinolysis help to trap and remove such debris. Lung inflammation in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may contribute to D-dimer levels additive to thrombosis in patients with COVID-19 (coronavirus disease 2019). Indeed, severe COVID-19 can lead to multiple activation events, including inflammation, primary and secondary hemostasis, and fibrinolysis, all of which may contribute to cumulative D-dimer development. Finally, D-dimer testing has also found a role in the diagnosis and triaging of the so-called (COVID-19) vaccine-induced thrombotic thrombocytopenia.

The humoral response and antibodies against SARS-CoV-2 infection

Two and a half years into the COVID-19 pandemic, we have gained many insights into the human antibody response to the causative SARS-CoV-2 virus. In this Review, we summarize key observations of humoral immune responses in people with COVID-19, discuss key features of infection- and vaccine-induced neutralizing antibodies, and consider vaccine designs for inducing antibodies that are broadly protective against different variants of the SARS-CoV-2 virus.

Homocysteine in coronavirus disease (COVID-19): a systematic literature review

OBJECTIVES

Coronavirus disease 2019 (COVID-19) is a life-threatening infectious disorder characterized by a sustained prothrombotic state. Since homocysteine is a potential biomarker of thrombotic diseases, the aim of this article is to provide an updated overview on the possible role played by hyperhomocysteinemia in influencing an unfavorable COVID-19 progression.

METHODS

We carried out an electronic search in Medline (PubMed interface) using the keywords ("COVID-19" OR "SARS-CoV-2") AND "homocysteine", between 2019 and the present time, with no language restrictions, to identify all articles which explored the concentration of homocysteine in COVID-19 patients with or without unfavorable disease progression.

RESULTS

Three studies, totaling 694 hospitalized COVID-19 patients, were included in our systematic review. Overall, the differences between the mean homocysteine values in non-severe vs. severe COVID-19 patients were always positive (i.e., 15.1%, 24.1% and 22.8%, generating a positive weight mean difference of 1.75 μmol/L (95%CI, 1.26-2.25 μmol/L; p=0.011), which translates into a cumulative difference of approximately ∼1.2 μmol/L.

CONCLUSIONS

Despite the limited evidence that has been garnered so far, increased homocysteine ​​levels may be a potentially useful marker for predicting the risk of unfavorable progression in patients with COVID-19.

Magnetofluid-Integrated Multicolor Immunochip for Visual Analysis of Neutralizing Antibodies to SARS-CoV-2 Variants

The global spread of SARS-CoV-2 virus has severely affected human health, life, and work. Vaccine immunization is considered to be an effective means to protect the body from infection. Therefore, timely analysis of the antibody level is helpful to identify people with low immune response or attenuated antibodies so as to carry out targeted and precise vaccine booster immunization. Herein, we develop a magnetofluid-integrated multicolor immunochip, as a sample-to-answer system in a fully enclosed space, for visual analysis of neutralizing antibodies of SARS-CoV-2. Generally, this chip adopts an innovative three-dimensional two-phase system that utilizes mineral oil to block the connection between reagent wells in the vertical direction and provides a wide interface for rapid and nondestructive shuttle of magnetic beads during the immunoassay. In order to obtain visualized signal output, gold nanorods with a size-dependent color effect are used as the colorful chromogenic substrates for evaluation of the antibody level. Using this chip, the neutralizing antibodies were successfully detected in vaccine-immunized volunteers with 83.3% sensitivity and 100% specificity. Furthermore, changes in antibody levels of the same individual over time were also reflected by the multicolor assay. Overall, benefiting from simple operation, airtight safety, and nonrequirement of external equipment, this platform can provide a new point-of-care testing strategy for alleviating the shortage of medical resources and promoting epidemic control in underdeveloped areas.

The Evolutionary Dance between Innate Host Antiviral Pathways and SARS-CoV-2

Compared to what we knew at the start of the SARS-CoV-2 global pandemic, our understanding of the interplay between the interferon signaling pathway and SARS-CoV-2 infection has dramatically increased. Innate antiviral strategies range from the direct inhibition of viral components to reprograming the host’s own metabolic pathways to block viral infection. SARS-CoV-2 has also evolved to exploit diverse tactics to overcome immune barriers and successfully infect host cells. Herein, we review the current knowledge of the innate immune signaling pathways triggered by SARS-CoV-2 with a focus on the type I interferon response, as well as the mechanisms by which SARS-CoV-2 impairs those defenses.

Total anti-SARS-CoV-2 antibodies measured 6 months after Pfizer-BioNTech COVID-19 vaccination in healthcare workers

Background

This study aimed at monitoring the kinetics of serum total anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) antibodies in a cohort of healthcare workers after voluntary vaccination with Pfizer-BioNTech coronavirus disease 2019 (COVID-19) mRNA-based vaccine.

Methods

The study population consisted of 787 healthcare workers (mean age 44±12 years; 66% females), who received two 30 mg doses of Pfizer-BioNTech COVID-19 vaccine, 3 weeks apart. Venous blood was drawn before the first vaccine dose, immediately before the second vaccine dose, and then at 1, 3 and 6 months after the second vaccine dose. Serological testing employed the total antiSARS-CoV-2 antibodies measurement with Roche Elecsys Anti-SARS-CoV-2 S chemiluminescent immunoassay.

Results

The median serum levels of total anti-SARS-CoV-2 antibodies reached the peak (1762 kU/L) 1 month after the second vaccine dose, but tended to progressively decline at the 3-month (1086 kU/L) and 6-month (802 kU/L) follow-up points. Overall, the values after 3and 6months were 37% and 57% lower than the corresponding concentrations measured at the peak. No healthcare worker had total anti-SARS-CoV-2 antibodies below the method-dependent cut-off after 6 months. The decline compared to the peak was more accentuated in baseline seropositive persons than in those who were baseline seronegative (74% vs. 52%) cohort. The 6-month post-vaccination anti-SARS-CoV-2 antibodies in subjects aged <65 years remained over 2-fold higher than in those aged ≥65 years (813 vs. 343 kU/L) and also remained consistently higher in women than in men.

Conclusions

Gradual decline of total anti-SARS-CoV-2 antibodies occurred 6 months after Pfizer-BioNTech COVID-19 vaccination, though values remained higher than the method-dependent cut-off, with no case of sero-negativization.

Inhibitory mechanism of Ambroxol and Bromhexine Hydrochlorides as potent blockers of molecular interaction between SARS-CoV-2 spike protein and human angiotensin-converting Enzyme-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects the host cells through interaction of its spike protein with human angiotensin-converting enzyme 2 (hACE-2). High binding affinity between the viral spike protein and host cells hACE-2 receptor has been reported to enhance the viral infection. Thus, the disruption of this molecular interaction will lead to reduction in viral infectivity. This study, therefore, aimed to analyze the inhibitory potentials of two mucolytic drugs; Ambroxol hydrochlorides (AMB) and Bromhexine hydrochlorides (BHH), to serve as potent blockers of these molecular interactions and alters the binding affinity/efficiency between the proteins employing computational techniques. The study examined the effects of binding of each drug at the receptor binding domain (RBD) of the spike protein and the exopeptidase site of hACE-2 on the binding affinity (ΔG_bind) and molecular interactions between the two proteins. Binding affinity revealed that the binding of the two drugs at the RBD-ACE-2 site does not alter the binding affinity and molecular interaction between the proteins. However, the binding of AMB (−56.931 kcal/mol) and BHH (−46.354 kcal/mol) at the exopeptidase site of hACE-2, significantly reduced the binding affinities between the proteins compared to the unbound, ACE-2-RBD complex (−64.856 kcal/mol). The result further showed the two compounds have good affinity at the hACE-2 site, inferring they might be potent inhibitors of hACE-2. Residue interaction networks analysis further revealed the binding of the two drugs at the exopeptidase site of hACE-2 reduced the number of interacting amino residues, subsequently leading to loss of interactions between the two proteins, with BHH showing better reduction in the molecular interaction and binding affinity than AMB. The result of the structural analyses additionally, revealed that the binding of the drugs considerably influences the dynamic of the complexes when compared to the unbound complex. The findings from this study suggest the binding of the two drugs at the exopeptidase site reduces the binding effectiveness of the proteins than their binding at the RBD site, and consequently might inhibit viral attachment and entry.

Early prediction of COVID-19-associated acute kidney injury: Are serum NGAL and serum Cystatin C levels better than serum creatinine?

BACKGROUND

Coronavirus disease-2019 (COVID-19) is associated with a high risk of acute kidney injury (AKI), often requiring renal replacement therapy (RRT). Serum Cystatin C (sCysC) and serum Neutrophil Gelatinase-Associated Lipocalin (sNGAL) are emerging biomarkers for kidney injury, and were suggested to be superior to serum creatinine (sCr) in several clinical settings. Moreover, elevated sCysC is associated with disease severity and mortality in COVID-19. We aimed to assess the utility of sCysC and sNGAL for predicting COVID-19-associated AKI, need for RRT, and need for intensive care unit (ICU) admission, when measured at presentation to the emergency department (ED).

METHODS

Patients presenting to the ED with laboratory-confirmed COVID-19 were included. The primary outcome was development of COVID-19-associated AKI, while the secondary outcomes were need for RRT and ICU admission.

RESULTS

Among 52 COVID-19 patients, 22 (42.3%) developed AKI with 8/22 (36.4%) requiring RRT. Both sCr and sCysC demonstrated excellent performance for predicting AKI (AUC, 0.86 and 0.87, respectively) and need for RRT (AUC, 0.94 and 0.95, respectively). sNGAL displayed acceptable performance for predicting AKI (AUC, 0.81) and need for RRT (AUC, 0.87).

CONCLUSIONS

SCr and sCysC measured at ED presentation are both highly accurate predictors of AKI and need for RRT, whereas sNGAL demonstrated adequate diagnostic performance. While sCyC was previously shown to be superior to sCr as a diagnostic biomarker of kidney injury in certain etiologies, our findings demonstrate that sCr is comparable to sCyC in the context of predicting COVID-19-associated AKI. Given the high sensitivity of these biomarkers for predicting the need for RRT, and as sCysC is associated with mortality in COVID-19 patients, we recommend their measurement for enabling risk stratification and early intervention.

Blocking EGFR with nimotuzumab: a novel strategy for COVID-19 treatment

Background: Lung injury and STAT1 deficit induce EGFR overexpression in SARS-CoV-2 infection. Patients & methods: A phase I/II trial was done to evaluate the safety and preliminary effect of nimotuzumab, an anti-EGFR antibody, in COVID-19 patients. Patients received from one to three infusions together with other drugs included in the national guideline. Results: 41 patients (31 severe and 10 moderate) received nimotuzumab. The median age was 62 years and the main comorbidities were hypertension, diabetes and cardiovascular disease. The antibody was very safe and the 14-day recovery rate was 82.9%. Inflammatory markers decreased over time. Patients did not show signs of fibrosis. Conclusion: Nimotuzumab is a safe antibody that might reduce inflammation and prevent fibrosis in severe and moderate COVID-19 patients.

Clinical Trial Registration: RPCEC00000369 (rpcec.sld.cu).

Background: After SARS-CoV-2 infection, many cells in the lung express a new receptor called EGFR. Overexpression of EGFR can worsen the pulmonary disease and provoke fibrosis. Patients & methods: The initial impact of using a drug that blocks EGFR, nimotuzumab, was evaluated in COVID-19 patients. Results: 41 patients received nimotuzumab by the intravenous route together with other medications. The median age was 62 years, and patients had many chronic conditions including hypertension, diabetes and cardiac problems. Treatment was well tolerated and 82.9% of the patients were discharged by day 14. Serial laboratory tests, x-rays and CT scan evaluations showed the improvement of the patients. Conclusion: Nimotuzumab is a safe drug that can be useful to treat COVID-19 patients.

Development and validation of SCOPE score: A clinical score to predict COVID-19 pneumonia progression to severe respiratory failure

Most patients infected with SARS-CoV-2 (COVID-19) experience mild, non-specific symptoms, but many develop severe symptoms associated with an excessive inflammatory response. Elevated plasma concentrations of soluble urokinase plasminogen activator receptor (suPAR) provide early warning of progression to severe respiratory failure (SRF) or death, but access to suPAR testing may be limited. The Severe COvid Prediction Estimate (SCOPE) score, derived from circulating concentrations of C-reactive protein, D- dimers, interleukin-6, and ferritin among patients not receiving non-invasive or invasive mechanical ventilation during the SAVE-MORE study, offers predictive accuracy for progression to SRF or death within 14 days comparable to that of a suPAR concentration of ≥6 ng/mL (area under receiver operator characteristic curve 0.81 for both). The SCOPE score is validated in two similar independent cohorts. A SCOPE score of 6 or more is an alternative to suPAR for predicting progression to SRF or death within 14 days of hospital admission for pneumonia, and it can be used to guide treatment decisions.

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SCOPE score is composed of C-reactive protein, D dimers, ferritin, and interleukin-6

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Values of 6 or more predict 6-fold risk for severe respiratory failure or death

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SCOPE score predicts risk for severe respiratory failure or death comparable to suPAR

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Anakinra treatment when SCOPE is 6 or more provides lower odds of poor outcome

Effects of age, sex, serostatus, and underlying comorbidities on humoral response post-SARS-CoV-2 Pfizer-BioNTech mRNA vaccination: a systematic review

With the advent of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, several vaccines have been developed to mitigate its spread and prevent adverse consequences of the Coronavirus Disease 2019 (COVID-19). The mRNA technology is an unprecedented vaccine, usually given in two doses to prevent SARS-CoV-2 infections. Despite effectiveness and safety, inter-individual immune response heterogeneity has been observed in recipients of mRNA-based vaccines. As a novel disease, the specific immune response mechanism responsible for warding off COVID-19 remains unclear at this point. However, significant evidence suggests that humoral response plays a crucial role in affording immunoprotection and preventing debilitating sequelae from COVID-19. As such, this paper focused on the possible effects of age, sex, serostatus, and comorbidities on humoral response (i.e. total antibodies, IgG, and/or IgA) of different populations post-mRNA-based Pfizer-BioNTech vaccination. A systematic search of literature was performed through PubMed, Cochrane CENTRAL, Google Scholar, Science Direct, medRxiv, and Research Square. Studies were included if they reported humoral response to COVID-19 mRNA vaccines. A total of 32 studies were identified and reviewed, and the percent differences of means of reported antibody levels were calculated for comparison. Findings revealed that older individuals, male sex, seronegativity, and those with more comorbidities mounted less humoral immune response. Given these findings, several recommendations were proposed regarding the current vaccination practices. These include giving additional doses of vaccination for immunocompromised and elderly populations. Another recommendation is conducting clinical trials in giving a combined scheme of mRNA vaccines, protein vaccines, and vector-based vaccines.

Red Blood Cell Distribution Width in Hospitalized COVID-19 Patients

Introduction: Coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is causing dramatic morbidity and mortality worldwide. The Red Blood Cell Distribution Width (RDW) has been strongly associated with increased morbidity and mortality in multiple diseases.

Objective: To assess if elevated RDW is associated with unfavorable outcomes in hospitalized COVID-19.

Methods: We retrospectively studied clinical outcomes of hospitalized COVID-19 patients for their RDW values. In-hospital mortality was defined as primary outcome, while septic shock, need for mechanical ventilation, and length of stay (LOS) were secondary outcomes.

Results: A total of 294 COVID-19 patients were finally studied. Overall prevalence of increased RDW was 49.7% (146/294). RDW was associated with increased risk of in-hospital mortality (aOR, 4.6; 95%CI, 1.5-14.6) and septic shock (aOR, 4.6; 95%CI, 1.4-15.1) after adjusting for anemia, ferritin, lactate, and absolute lymphocyte count. The association remained unchanged even after adjusting for other clinical confounders such as age, sex, body mass index, coronary artery disease, hypertension, diabetes mellitus, and chronic obstructive pulmonary disease. No association was found instead with mechanical ventilation and median LOS.

Conclusion: Elevated RDW in hospitalized COVID-19 patients is associated with a significantly increased risk of mortality and septic shock.

Efficacy of COVID-19 vaccine booster doses in older people

Aim

COVID-19 vaccine efficacy is high in older people, but declines after 4–6 months.

Findings

Booster doses are effective for restoring COVID-19 vaccine efficacy in older people.

Message

COVID-19 vaccine boosters generate higher protection than primary vaccination.

Purpose

We provide here an updated analysis on efficacy of COVID-19 vaccine booster doses in older people (i.e., aged ≥ 80 years) based on ongoing Italian nationwide COVID-19 vaccination campaign.

Methods

Data were obtained from the COVID-19 national integrated surveillance program, made available and regularly updated by the Italian National Institute of Health.

Results

Compared to those who completed the COVID-19 vaccination cycle for ≥ 5 months (n = 2,385,897), those receiving booster doses (n = 1,549,747) had 75% lower risk of SARS-CoV-2 infection, 82–83% lower risk of COVID-19 hospitalization and ICU admission, and 81% lower risk of death. Administration of COVID-19 vaccine boosters generated also greater protection (between 63 and 87% higher) against all these same endpoints compared to early completing (i.e., < 5 months; n = 335,458) a primary COVID-19 vaccination cycle.

Conclusions

The administration of COVID-19 vaccine booster doses is advisable for reducing the risk of morbidity and mortality in older people.

Headache, anosmia, ageusia and other neurological symptoms in COVID-19: a cross-sectional study

Background

Neurological symptoms are frequent among patients with COVID-19. Little is known regarding the repercussions of neurological symptoms for patients and how these symptoms are related to one another.

Objectives

To determine whether there is an association between the neurological symptoms in patients with COVID-19, and to characterize the headache.

Method

This was a cross-sectional study. All hospital inpatients and health workers at the Hospital Universitario Oswaldo Cruz with a PCR-confirmed COVID-19 infection between March and June 2020 were considered for the study and were interviewed by telephone at least 2-months after the acute phase of the disease. These patients were identified by the hospital epidemiological surveillance department. A semi-structured questionnaire was used containing sociodemographic and clinical data and the ID-Migraine.

Results

A total of 288 patients was interviewed; 53.1% were male; with a median age of 49.9 (41.5–60.5) years; 91.7% presented some neurological symptom; 22.2% reported some neurological symptom as the symptom that troubled them most during COVID-19. Neurological symptoms were: ageusia (69.8%), headache (69.1%), anosmia (67%), myalgia (44.4%), drowsiness (37.2%), agitation (20.8%); mental confusion (14.9%), syncope (4.9%) and epileptic seizures (2.8%). Females, those who presented with fever, sore throat, anosmia/ageusia and myalgia also presented significantly more with headache (logistic regression). The most frequent headache phenotype was a non-migraine phenotype, was of severe intensity and differed from previous headaches. This persisted for more than 30 days in 18% and for more than 90 days in 10% of patients. Thirteen percent of those with anosmia and 11% with ageusia continued with these complaints after more than 90 days of the acute phase of the disease. Aged over 50 years, agitation and epileptic seizures were significantly associated with mental confusion (logistic regression).

Conclusion

Headache is frequent in COVID-19, is associated with other symptoms such as fever, sore throat, anosmia, ageusia, and myalgia, and may persist beyond the acute phase of the disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01367-8.

Anti-Endothelial Cell Antibodies are not frequently elevated in hospitalized patients with COVID-19

n/a.

Clostridioides difficile infection (CDI) during the COVID-19 pandemic

The ongoing coronavirus disease (COVID-19) pandemic has dramatically tested healthcare systems around the world, with serious repercussions on the measures of prevention and control of hospital-acquired infections (HAIs). Among HAIs, Clostridioides difficile infection (CDI) represents one of the most important global public health threats. Although the full impact of the COVID-19 pandemic on CDI remains undetermined, depending on the development of the pandemic in the coming months, in this review literature studies of the last three years have been considered in order to depict the current situation, and make some considerations about possible future developments. If on the one hand, a general reduction in CDI incidence has been reported in several settings, mainly due to the extraordinary reinforcement of infection prevention measures, on the other hand, the critical circumstances experienced in many hospitals have limited the effectiveness of these measures, particularly in the intensive care units (ICUs), increasing the possibility of the occurrence of hospital-acquired CDI (HA-CDI). New concerns have arisen from the decrease in C. difficile testing and the increased use of broad-spectrum antibiotics reported during the pandemic. In particular, overuse of antibiotics and disinfectants may lead to a selection of resistant C. difficile strains not only in hospitals but also in the community. Furthermore, patients infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and patients that have survived COVID-19 may represent a new group of frail patients potentially at a higher risk of CDI, a group that could potentially increase in size due to SARS-CoV-2 evolution. In the dramatic COVID-19 era, the multifactorial nature of CDI has emerged more clearly than before, highlighting the necessity of a strong refocus on efforts to improve prevention strategies and to integrate CDI surveillance in a One Health prospective in order to curtail the public health threat posed by this infection in the next future.

Anti-Endothelial Cell Antibodies are not frequently elevated in hospitalized patients with COVID-19

COVID-19 is now established to be associated with a thrombotic phenomenon, now called COVID-19 associated coagulopathy (CAC). Anti-Endothelial Cell Antibodies (AECA) are a heterogenous group of autoantibodies targeting various endothelial cell antigens or antigens adhering to endothelial cells, They are commonly observed in a variety of auto-immune and rheumatologic conditions, and were observed in patients with the severe acute respiratory syndrome (SARS) in 2005. We aimed to assess AECA status in patients with COVID-19 and their potential contributing role to endothelial injury and CAC. AECA identification was a relatively infrequent finding in COVID-19 patients on admission, and their presence, albeit in only 2/33 patients, was not associated with disease severity. However, as the autoantibodies were only measured at admission, we cannot exclude the possibility of pathogenic AECA developing later in the course of diseaseFurther studies using additional methods are needed to evaluate the presence and potential pathogenic role of AECA in later stages of COVID-19.

Testing Antigens, Antibodies, and Immune Cells in COVID-19 as a Public Health Topic—Experience and Outlines

The current COVID-19 pandemic has triggered an accelerated pace in all research domains, including reliable diagnostics methodology. Molecular diagnostics of the virus and its presence in biological samples relies on the RT-PCR method, the most used and validated worldwide. Nonconventional tests with improved parameters that are in the development stages will be presented, such as droplet digital PCR or CRISPR-based assays. These molecular tests were followed by rapid antigen testing along with the development of antibody tests, whether based on ELISA platform or on a chemiluminescent microparticle immunoassay. Less-conventional methods of testing antibodies (e.g., lateral flow immunoassay) are presented as well. Left somewhere in the backstage of COVID-19 research, immune cells and, furthermore, immune memory cells, are gaining the spotlight, more so in the vaccination context. Recently, methodologies using flow-cytometry evaluate circulating immune cells in infected/recovered patients. The appearance of new virus variants has triggered a surge for tests improvement. As the pandemic has entered an ongoing or postvaccination era, all methodologies that are used to monitor public health focus on diagnostic strategies and this review points out where gaps should be filled in both clinical and research settings.

Blood lactate concentration in COVID-19: a systematic literature review

Coronavirus disease 2019 (COVID-19) is an infectious respiratory condition sustained by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which manifests prevalently as mild to moderate respiratory tract infection. Nevertheless, in a number of cases the clinical course may deteriorate, with onset of end organ injury, systemic dysfunction, thrombosis and ischemia. Given the clinical picture, baseline assessment and serial monitoring of blood lactate concentration may be conceivably useful in COVID-19. We hence performed a systematic literature review to explore the possible association between increased blood lactate levels, disease severity and mortality in COVID-19 patients, including comparison of lactate values between COVID-19 and non-COVID-19 patients. We carried out an electronic search in Medline and Scopus, using the keywords "COVID-19" OR "SARS-CoV-2" AND "lactate" OR "lactic acid" OR "hyperlactatemia", between 2019 and present time (i.e. October 10, 2021), which allowed to identify 19 studies, totalling 6,459 patients. Overall, we found that COVID-19 patients with worse outcome tend to display higher lactate values than those with better outcome, although most COVID-19 patients in the studies included in our analysis did not have sustained baseline hyperlactatemia. Substantially elevated lactate values were neither consistently present in all COVID-19 patients who developed unfavourable clinical outcomes. These findings suggest that blood lactate monitoring upon admission and throughout hospitalization may be useful for early identification of higher risk of unfavourable COVID-19 illness progression, though therapeutic decisions based on using conventional hyperlactatemia cut-off values (i.e., 2.0 mmol/L) upon first evaluation may be inappropriate in patients with SARS-CoV-2 infection.

A Smart Helmet-Based PLS-BPNN Error Compensation Model for Infrared Body Temperature Measurement of Construction Workers during COVID-19

In the context of the long-term coexistence between COVID-19 and human society, the implementation of personnel health monitoring in construction sites has become one of the urgent needs of current construction management. The installation of infrared temperature sensors on the helmets required to be worn by construction personnel to track and monitor their body temperature has become a relatively inexpensive and reliable means of epidemic prevention and control, but the accuracy of measuring body temperature has always been a problem. This study developed a smart helmet equipped with an infrared temperature sensor and conducted a simulated construction experiment to collect data of temperature and its influencing factors in indoor and outdoor construction operation environments. Then, a Partial Least Square–Back Propagation Neural Network (PLS-BPNN) temperature error compensation model was established to correct the temperature measurement results of the smart helmet. The temperature compensation effects of different models were also compared, including PLS-BPNN with Least Square Regression (LSR), Partial Least Square Regression (PLSR), and single Back Propagation Neural Network (BPNN) models. The results showed that the PLS-BPNN model had higher accuracy and reliability, and the determination coefficient of the model was 0.99377. After using PLS-BPNN model for compensation, the relative average error of infrared body temperature was reduced by 2.745 °C and RMSE was reduced by 0.9849. The relative error range of infrared body temperature detection was only 0.005~0.143 °C.

Cardiac Biomarkers in COVID-19: A Narrative Review

The diagnosis and risk stratification of coronavirus disease 2019 (COVID-19) is primarily based on discretionary use of laboratory resources. Several lines of evidence now attest that cardiovascular disease not only is a frequent complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but its pre-existence may increase the risk of morbidity, disability, and death in patients with COVID-19. To this end, routine assessment of biomarkers of cardiac injury (i.e., cardiac troponin I or T) and dysfunction (e.g., natriuretic peptides) has emerged as an almost essential practice in patients with moderate, severe, and critical COVID-19 illness. Therefore, this narrative review aims to provide an overview of cardiac involvement in patients with SARS-CoV-2 infection as well as the clinical background for including cardiac biomarkers within specific panels of laboratory tests for managing COVID-19 patients.

High immature platelet fraction with reduced platelet count on hospital admission. Can it be useful for COVID-19 diagnosis?

Introduction

Health professions are heavily engaged facing the current threat of SARS‐CoV‐2 (COVID‐19). Although there are many diagnostic tools, an accurate and rapid laboratory procedure for diagnosing COVID‐19 is recommended. We focused on platelet parameters as the additional biomarkers for clinical diagnosis in patients presenting to the emergency department (ED).

Materials and Methods

Five hundred and sixty‐one patients from February to April 2020 have been recruited. Patients were divided into three groups: (N = 50) COVID‐19 positive and (N = 21) COVID‐19 negative with molecular testing, (N = 490) as reference population without molecular testing. A Multiplex rRT‐PCR from samples collected by nasopharyngeal swabs was performed and the hematological data collected.

Results

We detected a mild anemia in COVID‐19 group and lymphopenia against reference population: hemoglobin (g/dL) 13.0 (11.5‐14.8) versus 13.9 (12.8‐15.0) (P = .0135); lymphocytes (10⁹/L) 1.24 (0.94‐1.73) versus 1.99 (1.49‐2.64) (P < .0001). In addition, abnormal platelet parameters as follows (COVID group vs reference population): PLT (×10⁹/L) 209 (160‐258) vs 236 (193‐279) (P = .0239). IPF (%) 4.05 (2.5‐5.9) versus 3.4 (2.2‐4.9) (P = .0576); H‐IPF (%) 1.25 (0.8‐2.2) versus 0.95 (0.6‐1.5) (P = .0171) were identified. In particular, COVID positive group had a high H‐IPF/IPF Ratio compared to reference population [0.32 (0.29‐0.36) versus 0.29 (0.26‐0.32), respectively, (P = .0003)]. Finally, a PLT difference of nearly 50 × 10⁹/L between pre/postCOVID‐19 sampling for each patient was found (N = 42) (P = .0194).

Conclusions

COVID‐19 group results highlighted higher IPF and H‐IPF values, with increased H‐IPF/IPF Ratio, associated to PLT count reduction. These findings shall be adopted for a timely diagnosis of patients upon hospital admission.

Is body temperature mass screening a reliable and safe option for preventing COVID-19 spread?

With the ongoing coronavirus disease 2019 (COVID-19) pandemic continuing worldwide, mass screening of severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) infection is a cornerstone of strategies for limiting viral spread within communities. Although mass screening of body temperature with handheld, non-contact infrared thermometers and thermal imagine scanners is now widespread in a kaleidoscope of social and healthcare settings for the purpose of detecting febrile individuals bearing SARS-CoV-2 infection, this strategy carries some drawbacks, which will be highlighted and discussed in this article. These caveats basically include high rate of asymptomatic SARS-CoV-2 infections, the challenging definition of "normal" body temperature, variation of measured values according to the body district, false negative cases due to antipyretics, device inaccuracy, impact of environmental temperature, along with the low specificity of this symptom for screening COVID-19 in patients with other febrile conditions. Some pragmatic suggestions will also be endorsed for increasing accuracy and precision of mass screening of body temperature. These encompass the regular assessment of body temperature (possibly twice) with validated devices, which shall be constantly monitored over time and used following manufacturer's instructions, the definition of a range of "normal" body temperatures in the local population, patients interrogation on usual body temperature, measurement standardization of one body district, allowance of sufficient environmental acclimatization before temperature check, integration with contact history and other clinical information, along with exclusion of other causes of increased body temperature. We also endorse the importance of individual and primary care physician's regular and repeated check of personal body temperature.

The rapid adaptation of SARS-CoV-2-rise of the variants: transmission and resistance

The causative factor of COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is continuously mutating. Interestingly, identified mutations mainly occur in the spike (S) protein which interacts with the ACE2 receptor and is cleaved via serine protease TMPRSS2. Some mutated strains are becoming dominant in various parts of the globe because of increased transmissibility as well as cell entry efficacy. Remarkably, the neutralizing activity of monoclonal antibodies, convalescent sera, and vaccines against the variants has been reported to be significantly reduced. Therefore, the efficacy of various monoclonal antibodies therapy and vaccines against these variants is becoming a great global concern. We herein summarize the current status of SARS-CoV-2 with gears shifted towards the recent and most common genetic variants in relation to transmission, neutralizing activity, and vaccine efficacy.

C1-Inhibitor: Structure, Functional Diversity and Therapeutic Development

Human C1-Inhibitor (C1INH), also known as C1-esterase inhibitor, is an important multifunctional plasma glycoprotein that is uniquely involved in a regulatory network of complement, contact, coagulation, and fibrinolytic systems. C1INH belongs to a superfamily of serine proteinase inhibitor (serpins) and exhibits its inhibitory activities towards several target proteases of plasmatic cascades, operating as a major anti-inflammatory protein in the circulation. In addition to its inhibitory activities, C1INH is also involved in non-inhibitory interactions with some endogenous proteins, polyanions, cells and infectious agents. While C1INH is essential for multiple physiological processes, it is better known for its deficiency with regards to Hereditary Angioedema (HAE), a rare autosomal dominant disease clinically manifested by recurrent acute attacks of increased vascular permeability and edema. Since the link was first established between functional C1INH deficiency in plasma and HAE in the 1960s, tremendous progress has been made in the biochemical characterization of C1INH and its therapeutic development for replacement therapies in patients with C1INH-dependent HAE. Various C1INH biological activities, recent advances in the HAE-targeted therapies, and availability of C1INH commercial products have prompted intensive investigation of the C1INH potential for treatment of clinical conditions other than HAE. This article provides an updated overview of the structure and biological activities of C1INH, its role in HAE pathogenesis, and recent advances in the research and therapeutic development of C1INH; it also considers some trends for using C1INH therapeutic preparations for applications other than angioedema, from sepsis and endotoxin shock to severe thrombotic complications in COVID-19 patients.

Tofacitinib Use in Adults with Chronic Inflammatory Disease During the Severe Acute Respiratory Syndrome Coronavirus 2 Pandemic: What Is Known So Far?

Background

Concerns have been raised that the risk of severe acute respiratory syndrome coronavirus 2 infection, or more severe or critical coronavirus disease 2019 (COVID-19), may be higher in immunocompromised individuals receiving immunomodulatory therapies compared with immunocompetent individuals. Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis, psoriatic arthritis, ulcerative colitis, and polyarticular course juvenile idiopathic arthritis. To date, data on tofacitinib treatment during the COVID-19 pandemic are limited.

Objectives

To summarize current understanding of the use of tofacitinib in adults during the COVID-19 pandemic, and discuss research questions that are yet to be addressed, to further inform the safe and effective use of tofacitinib in clinical practice.

Methods

We conducted a review of the literature (as of February 2021), to summarize the expert recommendations for the management of rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis in the context of COVID-19, and to assess the current data regarding the use of tofacitinib in adult patients during the pandemic.

Results

Current recommendations for rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis state that tofacitinib treatment should be continued during the pandemic, except in cases of positive or presumed severe acute respiratory syndrome coronavirus 2 infection. However, limited data are available; analyses of data from international rheumatology and gastroenterology registries have suggested that tofacitinib may not be associated with an increased risk of hospitalization or treatment switching in adults with COVID-19.

Conclusions

Further assessment of tofacitinib use in patients with rheumatoid arthritis, psoriatic arthritis, or ulcerative colitis will be required to elucidate and establish the benefit:risk profile of tofacitinib during the current COVID-19 pandemic.

Association of COVID-19 transmission with high levels of ambient pollutants: Initiation and impact of the inflammatory response on cardiopulmonary disease

Ambient air pollution contributes to 7 million premature deaths annually. Concurrently, the ongoing coronavirus disease 2019 (COVID-19) pandemic, complicated with S-protein mutations and other variants, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in over 2.5 million deaths globally. Chronic air pollution-mediated cardiopulmonary diseases have been associated with an increased incidence of hospitalization and mechanical ventilation following COVID-19 transmission. While the underlying mechanisms responsible for this association remain elusive, air pollutant-induced vascular oxidative stress and inflammatory responses have been implicated in amplifying COVID-19-mediated cytokine release and vascular thrombosis. In addition, prolonged exposure to certain types of particulate matter (PM2.5, d < 2.5 μm) has also been correlated with increased lung epithelial and vascular endothelial expression of the angiotensin-converting enzyme-2 (ACE2) receptors to which the SARS-CoV-2 spike glycoproteins (S) bind for fusion and internalization into host cells. Emerging literature has linked high rates of SARS-CoV-2 infection to regions with elevated levels of PM2.5, suggesting that COVID-19 lockdowns have been implicated in regional reductions in air pollutant-mediated cardiopulmonary effects. Taken together, an increased incidence of SARS-CoV-2-mediated cardiopulmonary diseases seems to overlap with highly polluted regions. To this end, we will review the redox-active components of air pollutants, the pathophysiology of SARS-CoV-2 transmission, and the key oxidative mechanisms and ACE2 overexpression underlying air pollution-exacerbated SARS-CoV-2 transmission.

Protective Effects of Statins Administration in European and North American Patients Infected with COVID-19: A Meta-Analysis

Severe acute respiratory syndrome coronavirus 2 has spread rapidly throughout the world, becoming an overwhelming global health emergency. The array of injuries caused by this virus is broad and not limited to the respiratory system, but encompassing also extensive endothelial and systemic tissue damage. Since statins effectively improve endothelial function, these drugs may have beneficial effects in patients with coronavirus disease 2019 (COVID-19). Therefore, this investigation aimed to provide an updated overview on the interplay between statins and COVID-19, with particular focus on their potentially protective role against progression toward severe or critical illness and death. A systematic electronic search was performed in Scopus and PubMed up to present time. Data on statins use and COVID-19 outcomes especially in studies performed in Europe and North America were extracted and pooled. A total of seven studies met our inclusion criteria, totaling 2,398 patients (1,075 taking statins, i.e., 44.8%). Overall, statin usage in Western patients hospitalized with COVID-19 was associated with nearly 40% lower odds of progressing toward severe illness or death (odds ratio: 0.59; 95% confidence interval: 0.35-0.99). After excluding studies in which statin therapy was started during hospital admission, the beneficial effect of these drugs was magnified (odds ratio: 0.51; 95% confidence interval: 0.41-0.64). In conclusion, although randomized trials would be necessary to confirm these preliminary findings, current evidence would support a favorable effect of statins as adjuvant therapy in patients with COVID-19. Irrespective of these considerations, suspension of statin therapy seems highly unadvisable in COVID-19 patients.