Evaluation of Hepcidin Level in COVID-19 Patients Admitted to the Intensive Care Unit.

Coronavirus disease 2019 (COVID-19) presents a clinical spectrum that ranges from a mild condition to critical illness. Patients with critical illness present respiratory failure, septic shock and/or multi-organ failure induced by the so called "cytokine storm". Inflammatory cytokines affect iron metabolism, mainly inducing the synthesis of hepcidin, a hormone peptide not routinely measured. High levels of hepcidin have been associated with the severity of COVID-19. The aim of this study was to analyze, retrospectively, the levels of hepcidin in a group of COVID-19 patients admitted to the intensive care unit (ICU) of the Policlinico Tor Vergata of Rome, Italy. Thirty-eight patients from November 2020 to May 2021 were enrolled in the study. Based on the clinical outcome, the patients were assigned to two groups: survivors and non-survivors. Moreover, a series of routine laboratory parameters were monitored during the stay of the patients in the ICU and their levels correlated to the outcome. Statistical differences in the level of hepcidin, D-dimer, IL-6, LDH, NLR, neutrophils level, CRP, TNF-α and transferrin were observed between the groups. In particular, hepcidin values showed significantly different median concentrations (88 ng/mL vs. 146 ng/mL) between survivors and non-survivors. In addition, ROC curves analysis revealed sensitivity and specificity values of 74% and 76%, respectively, at a cut-off of 127 (ng/mL), indicating hepcidin as a good biomarker in predicting the severity and mortality of COVID-19 in ICU patients.

Predictive Value of MR-proADM in the Risk Stratification and in the Adequate Care Setting of COVID-19 Patients Assessed at the Triage of the Emergency Department.

In the past two pandemic years, Emergency Departments (ED) have been overrun with COVID-19-suspicious patients. Some data on the role played by laboratory biomarkers in the early risk stratification of COVID-19 patients have been recently published. The aim of this study is to assess the potential role of the new biomarker mid-regional proadrenomedullin (MR-proADM) in stratifying the in-hospital mortality risk of COVID-19 patients at the triage. A further goal of the present study is to evaluate whether MR-proADM together with other biochemical markers could play a key role in assessing the correct care level of these patients. Data from 321 consecutive patients admitted to the triage of the ED with a COVID-19 infection were analyzed. Epidemiological; demographic; clinical; laboratory; and outcome data were assessed. All the biomarkers analyzed showed an important role in predicting mortality. In particular, an increase of MR-proADM level at ED admission was independently associated with a threefold higher risk of IMV. MR-proADM showed greater ROC curves and AUC when compared to other laboratory biomarkers for the primary endpoint such as in-hospital mortality, except for CRP. This study shows that MR-proADM seems to be particularly effective for early predicting mortality and the need of ventilation in COVID-19 patients admitted to the ED.

Infection Rate of Respiratory Viruses in the Pandemic SARS-CoV-2 Period Considering Symptomatic Patients: Two Years of Ongoing Observations.

BACKGROUND: In the last two years, the SARS-CoV-2 pandemic has determined radical changes in human behaviors and lifestyles, with a drastic reduction in socialization due to physical distancing and self-isolation. These changes have also been reflected in the epidemiological patterns of common respiratory viruses. For this reason, early discrimination of respiratory viruses is important as new variants emerge. METHODS: Nasopharyngeal swabs of 2554 patients, with clinically suspected Acute Respiratory Infections (ARIs) from October 2019 to November 2021, were collected to detect 1 or more of the 23 common respiratory pathogens, especially viruses, via BioFilmArray RP2.1plus, including SARS-CoV-2. Demographical characteristics and epidemiological analyses were performed as well as a laboratory features profile of positive patients. RESULTS: An observational study on 2300 patients (254 patients were excluded because of missing data) including 1560 men and 760 women, median age of 64.5 years, was carried out. Considering the respiratory virus research request, most of the patients were admitted to the Emergency Medicine Department (41.2%, of patients), whereas 29.5% were admitted to the Infectious Diseases Department. The most frequently detected pathogens included SARS-CoV-2 (31.06%, 707/2300, from March 2020 to November 2021), InfA-B (1.86%, 43/2300), HCoV (2.17% 50/2300), and HSRV (1.65%, 38/2300). Interestingly, coinfection rates decreased dramatically in the SARS-CoV-2 pandemic period. The significative decrease in positive rate of SARS-CoV-2 was associated with the massive vaccination. CONCLUSION: This study represents a dynamic picture of the epidemiological curve of common respiratory viruses during the two years of pandemic, with a disregarded trend for additional viruses. Our results showed that SARS-CoV-2 had a preferential tropism for the respiratory tract without co-existing with other viruses. The possible causes were attributable either to the use of masks, social isolation, or to specific respiratory receptors mostly available for this virus, external and internal lifestyle factors, vaccination campaigns, and emergence of new SARS-CoV-2 variants.

Antibody response to COVID-19 vaccine: A point of view that can help to optimize dose distribution.

The global strategy to control coronavirus disease is based on the availability of COVID-19 vaccines. More information about response to a single dose vaccine could help to better understand and optimize the management of the vaccine campaign. Workers from the University of Rome "Tor Vergata" and the University Hospital of University of Rome "Tor Vergata," were monitored during their vaccination program. Serum samples were collected between the first and second dose and after the second dose. University personnel has been vaccinated with two doses of Vaxzevria vaccine 12 weeks apart, while hospital personnel has been vaccinated with two doses of Comirnaty 3 weeks apart. IgG antibodies (Abs) against the Receptor Binding Domain (RBD) of the virus spike surface glycoprotein and neutralizing antibodies (NT) anti-SARS-CoV-2 that block the interaction between RBD and the surface receptor cellular angiotensin converting enzyme (ACE2) were measured using the CL-series Mindray chemiluminescent assays, respectively. Different amounts of antibodies produced after the two doses of vaccine were found. Individuals with a previous natural infection developed a higher Abs titer. Among the individuals with no history of past SARS-CoV-2 infection, 5% had an Abs level of the same order of magnitude of infected people, suggesting that they acquired the infection in an asymptomatic way. In such individuals, one dose of vaccine may be sufficient to obtain a protective immune response.

Lactoferrin as Antiviral Treatment in COVID-19 Management: Preliminary Evidence.

Lactoferrin (Lf), a multifunctional cationic glycoprotein synthesized by exocrine glands and neutrophils, possesses an in vitro antiviral activity against SARS-CoV-2. Thus, we conducted an in vivo preliminary study to investigate the antiviral effect of oral and intranasal liposomal bovine Lf (bLf) in asymptomatic and mild-to-moderate COVID-19 patients. From April 2020 to June 2020, a total of 92 mild-to-moderate (67/92) and asymptomatic (25/92) COVID-19 patients were recruited and divided into three groups. Thirty-two patients (14 hospitalized and 18 in home-based isolation) received only oral and intranasal liposomal bLf; 32 hospitalized patients were treated only with standard of care (SOC) treatment; and 28, in home-based isolation, did not take any medication. Furthermore, 32 COVID-19 negative, untreated, healthy subjects were added for ancillary analysis. Liposomal bLf-treated COVID-19 patients obtained an earlier and significant (p < 0.0001) SARS-CoV-2 RNA negative conversion compared to the SOC-treated and untreated COVID-19 patients (14.25 vs. 27.13 vs. 32.61 days, respectively). Liposomal bLf-treated COVID-19 patients showed fast clinical symptoms recovery compared to the SOC-treated COVID-19 patients. In bLf-treated patients, a significant decrease in serum ferritin, IL-6, and D-dimers levels was observed. No adverse events were reported. These observations led us to speculate a potential role of bLf in the management of mild-to-moderate and asymptomatic COVID-19 patients.

The COVID-19 pandemic: viral variants and vaccine efficacy.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has prompted the scientific community and the pharmaceutical companies to put maximum efforts into developing vaccines to contain the spread of this disease. Presently, many vaccines have been developed and authorized for use in human beings in different countries. In particular, in Europe to date, the Pfizer-BioNTech, Moderna, AstraZeneca and Janssen COVID-19 vaccines have been authorized. All of them are based on a version of the spike (S) glycoprotein characterized at the beginning of the pandemic. However, they differ by their level of efficacy against COVID-19. SARS-COV-2, like other RNA viruses, mutates continually. Genome sequencing analysis shows a nucleotide substitution rate of about 1 × 10-3 substitutions per year that leads to the emergence of variants through point mutations, insertions, deletions and recombination. There is concern about the ability of the current vaccines to protect against emerging viral variants. Mutations in the S-glycoprotein may affect transmission dynamics and the risk of immune escape. In this review, we address the different technological platforms in use for developing COVID-19 vaccines, the impact of emerging viral variants on virus transmission, hospitalization, and response to current vaccines, as well as rare but important adverse reactions to them. Finally, different methods for measuring antibody response to the vaccines, including the importance of using the WHO International Standard to calibrate immunoassays accurately to an arbitrary unit, to reduce interlaboratory variation and to create a common language for reporting results, are reported.

Post-Mortem RT-PCR Assay for SARS-CoV-2 RNA in COVID-19 Patients' Corneal Epithelium, Conjunctival and Nasopharyngeal Swabs.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease has been described to possibly be associated with ocular surface disturbances. However, whether the virus could invade ocular tissues still remains elusive. In the present study, we tried to investigate the post-mortem presence of SARS-CoV-2 RNA in corneal epithelium gathered by patients with an ante-mortem confirmed diagnosis of Coronavirus disease-19 (COVID-19). Cadavers with an ante-mortem confirmed diagnosis of moderate to severe COVID-19 were examined. Clinical and demographic features were retrieved from hospital patients' notes. For each cadaver, corneal scrapings, conjunctival swabs (CS) and nasopharyngeal swabs (NPS) were collected to perform real-time reverse transcriptase polymerase chain reaction ((RT)-PCR) for SARS-CoV-2. Fourteen consecutive cadavers with an ante-mortem confirmed diagnosis of moderate to severe COVID-19 were examined. The last NPS performed ante-mortem confirmed SARS-CoV-2 infection in 12/14 (85.7%) patients. The mean death-to-swab time (DtS) was 3.15 ± 0.5 (2.10-5.1) h. The post-mortem NPS and CS found positive for SARS-CoV-2 RNA were 9/14 (64.3%) and 3/28 (10.7%), respectively. None of the corneal epithelium scrapes tested positive to RT-PCR for SARS-CoV-2 RNA. These data promote the SARS-CoV-2 as not able to contaminate the post-mortem corneal epithelium, while it can persist in different other structures of the ocular surface (i.e., the conjunctiva). It is reasonable to assume that such a contamination can occur ante-mortem too.

Evaluation of S-RBD and high specificity ACE-2-binding antibodies on SARS-CoV-2 patients after six months from infection.

The antibody response to SARS-CoV-2 has not yet fully defined, but the availability of sensitive and specific serological assays is crucial to observe the presence of specific antibodies against the human receptor binding domain (S-RBD) and high specificity ACE-2-binding antibodies or neutralizing antibodies (NT) in response to vaccines. Indeed, these peculiar antibodies should prevent viral interaction between RBD and Angiotensin-Converting Enzyme 2 (ACE2) receptor, located on surface of host cells. In this study, 72 samples from 37 hospitalized COVID-19 patients and 35 not-hospitalized patients were analyzed longitudinally. The detection of S-RBD and NT antibodies was carried out using CLIA tests. Hospitalized patients showed elevated serum levels of S-RBD (97.22%) and NT (77.78%) antibodies, differently, not-hospitalized, who were paucisymptomatic or asymptomatic patients, showed lower serum levels of S-RBD (65.71%) and NT (38.14%) antibodies. The results suggest that the NT serum level is strongly related to disease severity (p < 0.001) and to the serum level of S-RBD antibodies (p < 0.0001).

Lactoferrin Against SARS-CoV-2: In Vitro and In Silico Evidences.

Lactoferrin (Lf) is a cationic glycoprotein synthetized by exocrine glands and is present in all human secretions. It is also secreted by neutrophils in infection and inflammation sites. This glycoprotein possesses antimicrobial activity due to its capability to chelate two ferric ions per molecule, as well as to interact with bacterial and viral anionic surface components. The cationic features of Lf bind to cells, protecting the host from bacterial and viral injuries. Its anti-inflammatory activity is mediated by the ability to enter inside the nucleus of host cells, thus inhibiting the synthesis of proinflammatory cytokine genes. In particular, Lf down-regulates the synthesis of IL-6, which is involved in iron homeostasis disorders and leads to intracellular iron overload, favoring viral replication and infection. The well-known antiviral activity of Lf has been demonstrated against DNA, RNA, and enveloped and naked viruses and, therefore, Lf could be efficient in counteracting also SARS-CoV-2 infection. For this purpose, we performed in vitro assays, proving that Lf exerts an antiviral activity against SARS-COV-2 through direct attachment to both SARS-CoV-2 and cell surface components. This activity varied according to concentration (100/500 µg/ml), multiplicity of infection (0.1/0.01), and cell type (Vero E6/Caco-2 cells). Interestingly, the in silico results strongly supported the hypothesis of a direct recognition between Lf and the spike S glycoprotein, which can thus hinder viral entry into the cells. These in vitro observations led us to speculate a potential supplementary role of Lf in the management of COVID-19 patients.

The impact of the SARS-CoV-2 infection, with special reference to the hematological setting.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a disease known from a few months, caused by a recently arisen virus and, consequently, it is little known. The disease has a benign course in most infected subjects (children and young adults), is often symptomatic in adults over the age of 50 and often serious and life threatening in people with comorbidities and the elderly. The few data published on coronavirus disease-2019 (COVID-19) in the blood-oncology field report a serious clinical presentation, a serious course of the disease, and a high mortality rate, as has also been reported for other cancer contexts. The current strategy for treating patients with SARS-CoV-2 includes antivirals that are effective against other viral infections and drugs that can moderate the cytokine storm. There is no specific vaccine and consequently all possible precautions must be taken to prevent SARS-CoV-2 infection in the areas of oncology, oncohematology, and bone marrow transplantation. In this reviewer's article, we report the information currently available on SARS-CoV-2 infection to help young doctors and hematologists to successfully manage patients with COVID-19.

The importance of genomic analysis in cracking the coronavirus pandemic.

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has pushed the scientific community to undertake intense research efforts. Understanding SARS-CoV-2 biology is necessary to discover therapeutic or preventive strategies capable of containing the pandemic. Knowledge of the structural characteristics of the virus genome and proteins is essential to find targets for therapies and immunological interventions.Areas covered: This review covers different areas of expertise, genomic analysis of circulating strains, structural biology, viral mutations, molecular diagnostics, disease, and vaccines. In particular, the review is focused on the molecular approaches and modern clinical strategies used in these fields.Expert opinion: Molecular approaches to SARS-CoV-2 pandemic have been critical to shorten time for new diagnostic, therapeutic and prevention strategies. In this perspective, the entire scientific community is moving in the same direction. Vaccines, together with the development of new drugs to treat the disease, represent the most important strategy to protect human from viral disease and prevent further spread. In this regard, new molecular technologies have been successfully implemented. The use of a novel strategy of communication is suggested for a better diffusion to the broader public of new data and results.

SARS-CoV-2 Infection and the COVID-19 Pandemic Emergency: The Importance of Diagnostic Methods.

BACKGROUND: Currently, a pandemic of coronavirus disease 2019 (COVID-19) caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is underway, resulting in high morbidity and mortality across the globe. SUMMARY: A prompt and effective diagnosis is crucial to identify infected individuals, to monitor the infection, to perform contact tracing, and to limit the spread of the virus. Since the announcement of this public health emergency, several diagnostic methods have been developed including molecular and serological assays, and more recently biosensors. Here, we present the use of these assays as well as their main technical features, advantages, and limits. Key Messages: The development of reliable diagnostic assays is crucial not only for a correct diagnosis and containment of COVID-19 pandemic, but also for the decision-making process that is behind the clinical decisions, eventually contributing to the improvement of patient management. Furthermore, with the advent of vaccine and therapeutic monoclonal antibodies against SARS-CoV-2, serological assays will be instrumental for the validation of these new therapeutic options.

SARS-CoV-2 Lineages and Sub-Lineages Circulating Worldwide: A Dynamic Overview.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) originated in Wuhan, China, in early December 2019 has rapidly widespread worldwide, becoming one of the major global public health issues of the last centuries. Key Messages: Over the course of the pandemic, due to the advanced whole-genome sequencing technologies, an unprecedented amount of genomes have been generated, providing invaluable insights into the ongoing evolution and epidemiology of the virus during the pandemic. Therefore, this large amount of data played an important role in the SARS-CoV-2 mitigation and control strategies. Key Messages: The active monitoring and characterization of the SARS-CoV-2 lineages circulating worldwide is useful for a more specific diagnosis, better care, and timely treatment. In this review, a concise characterization of all the lineages and sub-lineages circulating and co-circulating across the world has been presented in order to determine the magnitude of the SARS-CoV-2 threat and to better understand the virus genetic diversity and its dispersion dynamics.

Performance of a rapid antigen test in the diagnosis of SARS-CoV-2 infection.

Diagnostics is crucial for a prompt identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected patients, their isolation and treatment. Real-time PCR is the reference method for the diagnosis of SARS-CoV-2 infection; however, the unprecedented increase in the number of infections worldwide calls for faster and easy methods that do not require skilled personnel and special equipment. Rapid antigen tests have been developed and used as first line screening. Here, we assessed the performance of a rapid antigen test in comparison to a real-time qualitative PCR as gold standard. Fifty nasopharyngeal swabs from suspected cases of SARS-CoV-2 infection have been tested by Coris coronavirus disease 2019 Ag Respi-Strip test and Allplex 2019n-CoV assay. Of the 50 nasopharyngeal swabs tested, 11 were negative by both tests, 27 were negative by Ag test but positive by real-time PCR, and 12 were positive by both methods. PCR detected the 39 positive samples at a median cycle threshold (Ct) value of 22.78 (mean: 24.51; range: 13.59-39.6). In the 12 concordant samples, the median Ct value was 17.37. The sensitivity of the Ag test was 30.77% (95% confidence interval [CI]: 17.02%-47.57%), specificity 100% (95% CI: 71.51%-100.00%), positive predictive value 100%, negative predictive value 85.25% (95% CI: 82.42%-87.69%), and accuracy 86.15% (95% CI: 73.45%-94.28%). The level of agreement between the two tests was poor, k = 0.164. The Ag test performs well in the presence of high viral loads, whereas lower levels are missed. Considering the poor sensitivity of the method, real-time PCR remains the gold standard as front line screening for SARS-CoV-2 infection.

SARS-CoV-2 infection serology validation of different methods: Usefulness of IgA in the early phase of infection.

BACKGROUND AND AIMS: A novel coronavirus (SARS-CoV-2) was isolated from the respiratory samples of patients with pneumonia as showed by the sequence analysis of the virus genomes obtained in Wuhan, China. The antibody response to SARS-CoV-2 is not well understood yet, but the availability of sensitive and specific serological assays will be crucial for the early diagnosis of infection, for epidemiological studies and for defining the presence of neutralizing antibodies in response to a possible vaccine. MATERIALS AND METHODS: We tested and compared the performances of one chemiluminescent immunoassay (CLIA), two enzyme-linked immunosorbent assay (ELISA) and an electrochemiluminescence immunoassay (ECLIA). RESULTS: The ECLIA serological assay performed best and may be a valid screening method for SARS-COV-2 infection. The IgA detected by the ELISA assay might be a more reliable and stable early serological marker than IgM. Instead, IgGs, as expected, showed stable level after 10 days from symptoms onset. CONCLUSION: The ECLIA method could be used as screening test, considering both the excellent performance and the cost per single test; while ELISA assay for IgG and IgA, which are present at a higher level than IgM and last longer, might be used as confirmatory test.

Evaluation of a new simultaneous anti-SARS-CoV-2 IgA, IgM and IgG screening automated assay based on native inactivated virus.

In addition to molecular testing, there is evolving interest for anti-SARS-CoV-2 antibodies serologic assays. Majority of them focus on IgM/IgG despite IgA important role in mucosal immunity. A simultaneous anti-SARS-CoV-2 IgA/IgG/IgM immunoassay, performed on an automated instrument by ELISA kit coated with native inactivated SARS-CoV-2, was detected on two control groups (negative swab healthcare workers; pre-pandemic healthy or with other viral infections individuals) and on two COVID-19 patient groups (early and late infection). Specificities were 100% in all groups, indicating no cross-reactivity with other infectious or pre-pandemic sera. Sensitivities were 94% in early infection group and 97% in total positive patient group, reaching 100% in late infection group. To our knowledge, this is the first technique based on native SARS-CoV-2. It is able to identify more positive samples than kits using recombinant antigens, therefore virus native epitopes as well as simultaneous anti-SARS-CoV-2 IgA/IgM/IgG detection could help to contain COVID-19 spreading.

The COVID-19 pandemic.

In December 2019, an outbreak of pneumonia of unknown origin was reported in Wuhan, Hubei Province, China. Pneumonia cases were epidemiologically linked to the Huanan Seafood Wholesale Market. Inoculation of respiratory samples into human airway epithelial cells, Vero E6 and Huh7 cell lines, led to the isolation of a novel respiratory virus whose genome analysis showed it to be a novel coronavirus related to SARS-CoV, and therefore named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 is a betacoronavirus belonging to the subgenus Sarbecovirus. The global spread of SARS-CoV-2 and the thousands of deaths caused by coronavirus disease (COVID-19) led the World Health Organization to declare a pandemic on 12 March 2020. To date, the world has paid a high toll in this pandemic in terms of human lives lost, economic repercussions and increased poverty. In this review, we provide information regarding the epidemiology, serological and molecular diagnosis, origin of SARS-CoV-2 and its ability to infect human cells, and safety issues. Then we focus on the available therapies to fight COVID-19, the development of vaccines, the role of artificial intelligence in the management of the pandemic and limiting the spread of the virus, the impact of the COVID-19 epidemic on our lifestyle, and preparation for a possible second wave.

Complete blood count might help to identify subjects with high probability of testing positive to SARS-CoV-2.

The SARS-CoV-2 pandemic has dramatically increased the workload for health systems and a consequent need to optimise resources has arisen, including the selection of patients for swab tests. We retrospectively reviewed consecutive patients presenting to the emergency department with symptoms suggestive of COVID-19 and undergoing swab tests for SARS-CoV-2. Complete blood counts (CBCs) were analysed looking for predictors of test positivity. Eight significant predictors were identified and used to build a 'complete' CBC score with a discriminatory power for COVID-19 diagnosis of AUC 92% (p<0.0001). When looking at the weight of individual variables, mean corpuscular volume (MCV), age, platelets and eosinophils (MAPE: MCV ≤90 fL, 65 points; age ≥45 years, 100 points; platelets ≤180×103/µL, 73 points; eosinophils <0.01/µL, 94 points) gave the highest contribution and were used to build a 'simplified' MAPE score with a discriminatory power of AUC 88%. By setting the cut-off MAPE score at ≥173 points, sensitivity and specificity for COVID-19 diagnosis were 83% and 82%, respectively, and the actual test positivity rate was 60% as compared to 6% of patients with MAPE score <173 points (odds ratio 23.04, 95% confidence interval [CI] 9.1-58.3, p-value <0.0001). In conclusion, CBC-based scores have potential for optimising the SARS-CoV-2 testing process: if these findings are confirmed in the future, swab tests may be waived for subjects with low score and uncertain symptoms, while they may be considered for asymptomatic or oligosymptomatic patients with high scores.