Prevalence of COVID-19 among blood donors: The Jordan University of Science and Technology experience

The corona virus disease-19 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, had health and economic results that profoundly affected communities worldwide. Investigating the seroprevalence of SARS-Cov-2 in blood donors is of a significant clinical and scientific value as it adds to knowledge about local herd immunity levels.To study the prevalence of SARS-Cov-2 infection among blood donors at a tertiary referral hospital in the north of Jordan.This is a prospective study that included all blood donors between September 2020 and March 2021. Donors’ IgG antibodies were qualitatively immunoassayed to determine the antibody status against SARS-CoV-2. The Elecsys Anti-SARS-CoV-2 technique was utilized.One thousand samples were tested by total antibody against SARS-CoV-2. The median age was 29 years, 96.7% were males. The seroprevalence was 14.5%, and 80% of the positive participants did not report previous COVID-19 infection. The seroprevalence of COVID-19 antibodies was less among smokers and those with an O blood group and higher among donors with an AB blood group.The prevalence of COVID-19 among healthy young blood donors at a tertiary teaching health facility in the north of Jordan was 14.5%. Smokers and those with an O blood group were less likely to be seropositive, as opposed to donors with an AB blood group.     

Cross-Reactive Antibodies to SARS-CoV-2 and MERS-CoV in Pre-COVID-19 Blood Samples from Sierra Leoneans

Many countries in sub-Saharan Africa have experienced lower COVID-19 caseloads and fewer deaths than countries in other regions worldwide. Under-reporting of cases and a younger population could partly account for these differences, but pre-existing immunity to coronaviruses is another potential factor. Blood samples from Sierra Leonean Lassa fever and Ebola survivors and their contacts collected before the first reported COVID-19 cases were assessed using enzyme-linked immunosorbent assays for the presence of antibodies binding to proteins of coronaviruses that infect humans. Results were compared to COVID-19 subjects and healthy blood donors from the United States. Prior to the pandemic, Sierra Leoneans had more frequent exposures than Americans to coronaviruses with epitopes that cross-react with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), SARS-CoV, and Middle Eastern respiratory syndrome coronavirus (MERS-CoV). The percentage of Sierra Leoneans with antibodies reacting to seasonal coronaviruses was also higher than for American blood donors. Serological responses to coronaviruses by Sierra Leoneans did not differ by age or sex. Approximately a quarter of Sierra Leonian pre-pandemic blood samples had neutralizing antibodies against SARS-CoV-2 pseudovirus, while about a third neutralized MERS-CoV pseudovirus. Prior exposures to coronaviruses that induce cross-protective immunity may contribute to reduced COVID-19 cases and deaths in Sierra Leone.     

Immunoglobulin (Ig)A seropositivity against SARS-CoV-2 in healthcare workers in Israel, 4 April to 13 July 2020: an observational study

IntroductionThe COVID-19 pandemic has put healthcare workers (HCW) at significant risk. Presence of antibodies can confirm prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.AimThis study investigates the prevalence of IgA and IgG antibodies against SARS-CoV-2 in HCW.MethodsPerformance of IgA and IgG antibody ELISA assays were initially evaluated in positive and negative SARS-CoV-2 serum samples. IgA and IgG antibodies against SARS-CoV-2 were measured in 428 asymptomatic HCW. We assessed the risk of two groups: HCW with high exposure risk outside work (HROW) residing in areas where COVID-19 was endemic (n = 162) and HCW with high exposure risk at work (HRAW) in a COVID-19 intensive care unit (ICU) (n = 97).ResultsSensitivities of 80% and 81.2% and specificities of 97.2% and 98% were observed for IgA and IgG antibodies, respectively. Of the 428 HCW, three were positive for IgG and 27 for IgA. Only 3/27 (11%) IgA-positive HCW had IgG antibodies compared with 50/62 (81%) in a group of previous SARS-CoV-2-PCR-positive individuals. Consecutive samples from IgA-positive HCW demonstrated IgA persistence 18–83 days in 12/20 samples and IgG seroconversion in 1/20 samples. IgA antibodies were present in 8.6% of HROW and 2% of HRAW.ConclusionsSARS-CoV-2 exposure may lead to asymptomatic transient IgA response without IgG seroconversion. The significance of these findings needs further study. Out of work exposure is a possible risk of SARS-CoV-2 infection in HCW and infection in HCW can be controlled if adequate protective equipment is implemented.     

Antibody-Dependent Enhancement of SARS-CoV-2 Infection of Human Immune Cells: In Vitro Assessment Provides Insight in COVID-19 Pathogenesis

Patients with COVID-19 generally raise antibodies against SARS-CoV-2 following infection, and the antibody level is positively correlated to the severity of disease. Whether the viral antibodies exacerbate COVID-19 through antibody-dependent enhancement (ADE) is still not fully understood. Here, we conducted in vitro assessment of whether convalescent serum enhanced SARS-CoV-2 infection or induced excessive immune responses in immune cells. Our data revealed that SARS-CoV-2 infection of primary B cells, macrophages and monocytes, which express variable levels of FcγR, could be enhanced by convalescent serum from COVID-19 patients. We also determined the factors associated with ADE, and found which showed a time-dependent but not viral-dose dependent manner. Furthermore, the ADE effect is not associated with the neutralizing titer or RBD antibody level when testing serum samples collected from different patients. However, it is higher in a medium level than low or high dilutions in a given sample that showed ADE effect, which is similar to dengue. Finally, we demonstrated more viral genes or dysregulated host immune gene expression under ADE conditions compared to the no-serum infection group. Collectively, our study provides insight into the understanding of an association of high viral antibody titer and severe lung pathology in severe patients with COVID-19.     

Prevalence of Anti-SARS-CoV-2 Specific Antibodies in Health-Care Workers Compared to General Population during an Early Phase of the Pandemic,Tehran-Iran

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapidly transmits in general population, mainly between health-care workers (HCWs) who are in close contact with patients. Objective: To study the seropositivity of HCWs as a high-risk group compared to general population. Methods: 72 samples were obtained from HCWs working in Masih Daneshvari hospital as one of the main COVID-19 admission centers in Tehran, during April 4 to 6, 2020. Also we collected 2021 blood samples from general population. The SARS-CoV-2 specific IgM, and IgG antibodies in the collected serum specimens were measured by commercial ELISA kits. Results: Based on the clinical manifestations, 25.0%, 47.2%, and 27.8% of HCWs were categorized as symptomatic with typical symptoms, symptomatic with atypical symptoms, and asymptomatic, respectively. Symptomatic individuals with typical and atypical symptoms were 63.2% and 36.8% positive in RT-PCR test, respectively. Anti-SARS-CoV-2 IgM and IgG antibodies were detected in 15.3% and 27.8% of HCWs samples, respectively. Antibody testing in the general population indicated that SARS-CoV-2 specific IgM and IgG were found in (162/2021) 8%, and (290/2021) 14.4%, respectively. The frequency of positive cases of IgM and IgG were significantly increased in HCWs compared to general population (p= 0.028 for IgM and p= 0.002 for IgG). Conclusion: The frequency of SARS-CoV-2 specific antibodies in HCWs was higher than general population indicating a higher viral transmission via close exposure with COVID-19 patients.     

Liver diseases in COVID-19:Etiology,treatment and prognosis

In December 2019, a novel coronavirus named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) was identified in Wuhan, China causing coronavirus disease-2019(COVID-19). Numerous studies have shown varying degrees of liver damage in patients infected with SARS-CoV-2. However, in previous case studies of COVID-19, the exact cause of liver injury has not been clearly elucidated, nor is there clear evidence of the interaction between liver injury and COVID-19. This study will analyze the causes of liver injury in COVID-19 and the influence of liver-related complications on the treatment and prognosis of COVID-19.     

Anakinra,una alternativa potencial en el tratamiento de la infección respiratoria grave por SARS-CoV-2 refractaria a tocilizumab

SARS-CoV-2 is a new RNA virus which causes coronavirus disease 2019 (COVID-19), declared a pandemic by the World Health Organization (WHO). It triggers an atypical pneumonia that can progress to multiorgan failure. COVID-19 can cause dysregulation of the immune system, triggering an inflammatory response, and simulate haemophagocytic lymphohistiocytosis. Several studies have proposed that anti-IL-6 receptor antibodies, such as tocilizumab, play an important role in the treatment of severe acute respiratory infection associated with SARS-CoV-2. However, the role of anti-IL-1 receptor antibodies, such as anakinra, in the treatment of COVID-19 has not been established.We present a case report of a 51-year-old man diagnosed with severe respiratory infection associated with SARS-CoV-2 that was refractory to antiviral and anti-IL-6 treatment, with a favourable clinical outcome and analytical improvement after treatment with anti-IL-1 (anakinra).     

Molecular mechanisms implicated in SARS-CoV-2 liver tropism

The coronavirus disease 2019 (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Hepatic involvement is common in SARS-CoV-2-infected individuals. It is currently accepted that the direct and indirect hepatic effects of SARS-CoV-2 infection play a significant role in COVID-19. In individuals with pre-existing infectious and non-infectious liver disease, who are at a remarkably higher risk of developing severe COVID-19 and death, this pathology is most medically relevant. This review emphasizes the current pathways regarded as contributing to the gastrointestinal and hepatic ailments linked to COVID-19-infected patients due to an imbalanced interaction among the liver, systemic inflammation, disrupted coagulation, and the lung.     

Seroprevalence of SARS-CoV-2 antibodies among 925 staff members in an urban hospital accepting COVID-19 patients in Osaka prefecture,Japan: A cross-sectional study

The subclinical severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rate in hospitals during the pandemic remains unclear. To evaluate the effectiveness of our hospital''s current nosocomial infection control measures, we conducted a serological survey of anti-SARS-CoV-2 antibodies (immunoglobulin [Ig] G) among the staff of our hospital, which is treating coronavirus disease 2019 (COVID-19) patients.The study design was cross-sectional. We measured anti-SARS-CoV-2 IgG in the participants using a laboratory-based quantitative test (Abbott immunoassay), which has a sensitivity and specificity of 100% and 99.6%, respectively. To investigate the factors associated with seropositivity, we also obtained some information from the participants with an anonymous questionnaire. We invited 1133 staff members in our hospital, and 925 (82%) participated. The mean age of the participants was 40.0 ± 11.8 years, and most were women (80.0%). According to job title, there were 149 medical doctors or dentists (16.0%), 489 nurses (52.9%), 140 medical technologists (14.2%), 49 healthcare providers (5.3%), and 98 administrative staff (10.5%). The overall prevalence of seropositivity for anti-SARS-CoV-2 IgG was 0.43% (4/925), which was similar to the control seroprevalence of 0.54% (16/2970) in the general population in Osaka during the same period according to a government survey conducted with the same assay. Seropositive rates did not significantly differ according to job title, exposure to suspected or confirmed COVID-19 patients, or any other investigated factors.The subclinical SARS-CoV-2 infection rate in our hospital was not higher than that in the general population under our nosocomial infection control measures.     

浅谈新型冠状病毒疫苗的研发

目前,全球新型冠状病毒肺炎(COVID-19)感染人数达数千万,远超过2002-2003年严重急性呼吸综合征冠状病毒的感染人数。由于当前对于严重急性呼吸综合征冠状病毒、中东呼吸综合征冠状病毒及新型冠状病毒的致病机制并非十分清楚,也没有专门预防和治疗的特效药物,对于传播如此迅速的新型冠状病毒,有效的防控措施十分重要。而疫...     

Human ACE2 Polymorphisms from Different Human Populations Modulate SARS-CoV-2 Infection

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in over 6 million deaths worldwide. The high variability in COVID-19 symptoms remains one of the most interesting mysteries of the pandemic. Genetic and environmental factors are likely to be key determinants of COVID-19 symptomatology. Here, we explored ACE2 as a genetic determinant for SARS-CoV-2 infection and COVID-19 symptomatology. Each human genome encodes two alleles of ACE2, which encodes the cell entry receptor for SARS-CoV-2. Here, we determined whether naturally occurring human ACE2 (hACE2) polymorphisms in the human population affect SARS-CoV-2 infection and the severity of COVID-19 symptoms. ACE2 variants S19P, I21V, E23K, K26R, K31R, N33I, H34R, E35K, and T92I showed increased virus infection compared to wild-type ACE2; thus, these variants could increase the risk for COVID-19. In contrast, variants D38V, Y83H, I468V, and N638S showed reduced infection, indicating a potential protective effect. hACE2 variants K26R and T92I increased infection by three-fold without changing the levels of ACE2 on the surface of the cells, suggesting that these variants may increase the risk of severe COVID-19. On the contrary, hACE2 variants D38V and Y83H decreased SARS-CoV-2 infection by four- and ten-fold, respectively, without changing surface expression, suggesting that these variants may protect against severe COVID-19. Remarkably, all protective hACE2 Polymorphisms were found almost exclusively in Asian populations, which may provide a partial explanation for the low COVID-19 mortality rates in Asian countries. Thus, hACE2 polymorphisms may modulate susceptibility to SARS-CoV-2 in the host and partially account for the differences in severity of COVID-19 among different ethnic groups.     

Rapid Biosensor of SARS-CoV-2 Using Specific Monoclonal Antibodies Recognizing Conserved Nucleocapsid Protein Epitopes

Coronavirus disease 2019 (COVID-19), the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is characterized by symptoms such as fever, fatigue, a sore throat, diarrhea, and coughing. Although various new vaccines against COVID-19 have been developed, early diagnostics, isolation, and prevention remain important due to virus mutations resulting in rapid and high disease transmission. Amino acid substitutions in the major diagnostic target antigens of SARS-CoV-2 may lower the sensitivity for the detection of SARS-CoV-2. For this reason, we developed specific monoclonal antibodies that bind to epitope peptides as antigens for the rapid detection of SARS-CoV-2 NP. The binding affinity between antigenic peptides and monoclonal antibodies was investigated, and a sandwich pair for capture and detection was employed to develop a rapid biosensor for SARS-CoV-2 NP. The rapid biosensor, based on a monoclonal antibody pair binding to conserved epitopes of SARS-CoV-2 NP, detected cultured virus samples of SARS-CoV-2 (1.4 × 10³ TCID₅₀/reaction) and recombinant NP (1 ng/mL). Laboratory confirmation of the rapid biosensor was performed with clinical specimens (n = 16) from COVID-19 patients and other pathogens. The rapid biosensor consisting of a monoclonal antibody pair (75E12 for capture and the 54G6/54G10 combination for detection) binding to conserved epitopes of SARS-CoV-2 NP could assist in the detection of SARS-CoV-2 NP under the circumstance of spreading SARS-CoV-2 variants.     

Ensuring trust in COVID-19 data: A retrospective cohort study

There are no standardized methods for collecting and reporting coronavirus disease-2019 (COVID-19) data. We aimed to compare the proportion of patients admitted for COVID-19-related symptoms and those admitted for other reasons who incidentally tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).Retrospective cohort studyData were sampled twice weekly between March 26 and June 6, 2020 from a “COVID-19 dashboard,” a system-wide administrative database that includes the number of hospitalized patients with a positive SARS-CoV-2 polymerase chain reaction test. Patient charts were subsequently reviewed and the principal reason for hospitalization abstracted.Data collected during a statewide lockdown revealed that 92 hospitalized patients had positive SARS-CoV-2 test results. Among these individuals, 4.3% were hospitalized for reasons other than COVID-19-related symptoms but were incidentally found to be SARS-CoV-2-positive. After the lockdown was suspended, the total inpatient census of SARS-CoV-2-positive patients increased to 128, 20.3% of whom were hospitalized for non-COVID-19-related complaints.In the absence of a statewide lockdown, there was a significant increase in the proportion of patients admitted for non-COVID-19-related complaints who were incidentally found to be SARS-CoV-2-positive. In order to ensure data integrity, coding should distinguish between patients with COVID-19-related symptoms and asymptomatic patients carrying the SARS-CoV-2 virus.     

新型冠状病毒肺炎研究进展

2019年12月底,中国暴发了一场不明微生物引发的病毒性肺炎。经研究确认,该不明微生物为一种新的冠状病毒,即严重急性呼吸综合征冠状病毒2（severe acute respiratory syndrome coronavirus 2, SARS-CoV-2）,2020年2月,WHO将SARS-CoV-2感染的肺炎正式命名为新型冠状病毒肺炎（coronavirus disease-2019, COVID-19）。随着对SARS-CoV-2及其引发肺炎研究的深入,SARS-CoV-2特点、COVID-19临床及流行病学特征、临床诊治技术等研究内容陆续在国内外杂志报道。本文对已开展的COVID-19研究工作梳理总结,围绕溯源分析、检测手段、临床表现、药物研发、病毒传播等5个方面进行综述,以期对临床及科研工作者提供帮助。     

COVID-19 cynomolgus macaque model reflecting human COVID-19 pathological conditions

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global threat to human health and life. A useful pathological animal model accurately reflecting human pathology is needed to overcome the COVID-19 crisis. In the present study, COVID-19 cynomolgus monkey models including monkeys with underlying diseases causing severe pathogenicity such as metabolic disease and elderly monkeys were examined. Cynomolgus macaques with various clinical conditions were intranasally and/or intratracheally inoculated with SARS-CoV-2. Infection with SARS-CoV-2 was found in mucosal swab samples, and a higher level and longer period of viral RNA was detected in elderly monkeys than in young monkeys. Pneumonia was confirmed in all of the monkeys by computed tomography images. When monkeys were readministrated SARS-CoV-2 at 56 d or later after initial infection all of the animals showed inflammatory responses without virus detection in swab samples. Surprisingly, in elderly monkeys reinfection showed transient severe pneumonia with increased levels of various serum cytokines and chemokines compared with those in primary infection. The results of this study indicated that the COVID-19 cynomolgus monkey model reflects the pathophysiology of humans and would be useful for elucidating the pathophysiology and developing therapeutic agents and vaccines.

At the end of 2019, cases of infection with a novel coronavirus, later named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), that causes various respiratory symptoms expanded globally from China. On 11 March 2020, the World Health Organization declared a pandemic status based on the spread of infection worldwide and increase in the number of deaths. The outbreak of SARS-CoV-2 has resulted in a miserable reality for global health and life, and infection cases are continuing to increase worldwide. A detailed understanding of pathological conditions and development of effective therapeutic agents are needed to overcome the pandemic of diseases caused by SARS-CoV-2 infection, which has been named COVID-19. A new strategy including the development of pharmaceutical products and the use of appropriate animal models reflecting the human pathogenesis of COVID-19 is required.The common clinical features of COVID-19 are respiratory symptoms associated with pneumonia including fever, cough, myalgia, fatigue, dyspnea, and lymphopenia (1). COVID-19 symptoms range from no symptoms to severe symptoms. COVID-19 has shown severe pathogenicity in people with underlying diseases and in elderly people (2, 3). The period from onset of COVID-19 symptoms to death varies depending on the age of the patient and underlying disease status of the patient (4). Therefore, in addition to elucidating the pathological features in healthy individuals, it is necessary to elucidate the pathological conditions in patients with underlying diseases and in elderly patients.Cynomolgus monkeys (CMs), which are common laboratory animals among nonhuman primates (NHPs), show various human-like characteristics, including higher brain functions, long life span, single pregnancy, and regular menstrual periods, which are not found in other experimental animals. In the present study, COVID-19 model CMs, including healthy young CMs, elderly CMs (23 to 30 y of age, equivalent to 69 to 90 y of age in humans), and CMs with underlying diseases including diabetes and hyperlipidemia were experimentally infected with SARS-CoV-2 as animal models reflecting human pathology.