The antiviral compound remdesivir potently inhibits RNA-dependent RNA polymerase from Middle East respiratory syndrome coronavirus.

Antiviral drugs for managing infections with human coronaviruses are not yet approved, posing a serious challenge to current global efforts aimed at containing the outbreak of severe acute respiratory syndrome-coronavirus 2 (CoV-2). Remdesivir (RDV) is an investigational compound with a broad spectrum of antiviral activities against RNA viruses, including severe acute respiratory syndrome-CoV and Middle East respiratory syndrome (MERS-CoV). RDV is a nucleotide analog inhibitor of RNA-dependent RNA polymerases (RdRps). Here, we co-expressed the MERS-CoV nonstructural proteins nsp5, nsp7, nsp8, and nsp12 (RdRp) in insect cells as a part a polyprotein to study the mechanism of inhibition of MERS-CoV RdRp by RDV. We initially demonstrated that nsp8 and nsp12 form an active complex. The triphosphate form of the inhibitor (RDV-TP) competes with its natural counterpart ATP. Of note, the selectivity value for RDV-TP obtained here with a steady-state approach suggests that it is more efficiently incorporated than ATP and two other nucleotide analogs. Once incorporated at position i, the inhibitor caused RNA synthesis arrest at position i + 3. Hence, the likely mechanism of action is delayed RNA chain termination. The additional three nucleotides may protect the inhibitor from excision by the viral 3'-5' exonuclease activity. Together, these results help to explain the high potency of RDV against RNA viruses in cell-based assays.

Detection of Coronaviruses Using RNA Toehold Switch Sensors.

A rapid, sensitive and simple point-of-care (POC) nucleic acid diagnostic test is needed to prevent spread of infectious diseases. Paper-based toehold reaction, a recently emerged colorimetric POC nucleic acid diagnostic test, has been widely used for pathogen detection and microbiome profiling. Here, we introduce an amplification method called reverse transcription loop-mediated amplification (RT-LAMP) prior to the toehold reaction and modify it to enable more sensitive and faster colorimetric detection of RNA viruses. We show that incorporating the modified RT-LAMP to the toehold reaction detects as few as 120 copies of coronavirus RNA in 70 min. Cross-reactivity test against other coronaviruses indicates this toehold reaction with the modified RT-LAMP is highly specific to the target RNA. Overall, the paper-based toehold switch sensors with the modified RT-LAMP allow fast, sensitive, specific and colorimetric coronavirus detection.

Neuroimaging and neurologic findings in COVID-19 and other coronavirus infections: A systematic review in 116 patients.

Various neurologic syndromes have been described in patients with COVID-19 and other coronavirus infections. In this paper, we systematically reviewed the available imaging findings of patients diagnosed with neurological symptoms associated with coronavirus infections. Diverse radiologic results in the context of different neurologic presentations have been demonstrated using CT and MRI. While many patients have normal imaging evaluations, some patients present with intra-axial and extra-axial abnormalities. Stroke (both ischemic and hemorrhagic), encephalomyelitis, meningitis, demyelinating disorders such as acute disseminated encephalomyelitis (ADEM), and encephalopathy have been reported. Familiarity with these radiologic patterns will guide radiologists and referring clinicians to consider coronavirus infections in patients with worsening or progressive neurologic findings, particularly during the current COVID-19 pandemic. As data on this topic is very limited, further research and investigation are required.

Identification and design of novel small molecule inhibitors against MERS-CoV papain-like protease via high-throughput screening and molecular modeling.

The development of new therapeutic agents against the coronavirus causing Middle East Respiratory Syndrome (MERS) is a continuing imperative. The initial MERS-CoV epidemic was contained entirely through public health measures, but episodic cases continue, as there are currently no therapeutic agents effective in the treatment of MERS-CoV, although multiple strategies have been proposed. In this study, we screened 30,000 compounds from three different compound libraries against one of the essential proteases, the papain-like protease (PLpro), using a fluorescence-based enzymatic assay followed by surface plasmon resonance (SPR) direct binding analysis for hit confirmation. Mode of inhibition assays and competition SPR studies revealed two compounds to be competitive inhibitors. To improve upon the inhibitory activity of the best hit compounds, a small fragment library consisting of 352 fragments was screened in the presence of each hit compound, resulting in one fragment that enhanced the IC50 value of the best hit compound by 3-fold. Molecular docking and MM/PBSA binding energy calculations were used to predict potential binding sites, providing insight for design and synthesis of next-generation compounds.

[Coronaviruses as the cause of respiratory infections]. / Coronaviren als Ursache respiratorischer Infektionen.

BACKGROUND: There are six human pathogenic coronaviruses (CoV), which mainly cause infections of the respiratory system. In everyday clinical practice, it is helpful to know the relevance and characteristics of these pathogens. OBJECTIVE: To present the epidemiology, clinical picture and differences of human pathogenic CoV and to provide information on the diagnostics and treatment of patients suspected of having CoV infections. MATERIAL AND METHODS: Selective literature search, presentation of results and discussion of fundamental works and expert recommendations, including publications by the World Health Organization (WHO), the European Centre for Disease Prevention and Control (ECDC) and the Robert Koch Institute. RESULTS: The four endemic human CoVs (HCoV-NL63, HCoV-229E, HCoV-OC43 and HCoV-HKU1) mainly cause mild respiratory tract infections. In addition to these four endemic HCoV, the two epidemic CoV, severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV can cause severe pneumonia. The SARS-CoV has not been detected in humans in the last 15 years and MERS-CoV has been circulating mainly on the Arabian Peninsula since 2012; however, neither a specific treatment nor approved vaccines exist for any of the six human pathogenic CoVs. CONCLUSION: All six human CoVs can be diagnosed using RT-PCR on respiratory specimens but this is rarely necessary for the four endemic strains. In current clinical practice SARS-CoV has no importance as it has not been detected in humans for 15 years; however, a possible MERS-CoV infection should be taken into account in patients with typical symptoms and travel history to endemic regions. In this case, rapid diagnostic and general hygiene practices are important to prevent further transmission.

DPP4, the Middle East Respiratory Syndrome Coronavirus Receptor, is Upregulated in Lungs of Smokers and Chronic Obstructive Pulmonary Disease Patients.

Background: Middle East respiratory syndrome coronavirus (MERS-CoV) causes pneumonia with a relatively high case fatality rate in humans. Smokers and chronic obstructive pulmonary disease (COPD) patients have been reported to be more susceptible to MERS-CoV infection. Here, we determined the expression of MERS-CoV receptor, dipeptidyl peptidase IV (DPP4), in lung tissues of smokers without airflow limitation and COPD patients in comparison to nonsmoking individuals (never-smokers). Methods: DPP4 expression was measured in lung tissue of lung resection specimens of never-smokers, smokers without airflow limitation, COPD GOLD stage II patients and in lung explants of end-stage COPD patients. Both control subjects and COPD patients were well phenotyped and age-matched. The mRNA expression was determined using qRT-PCR and protein expression was quantified using immunohistochemistry. Results: In smokers and subjects with COPD, both DPP4 mRNA and protein expression were significantly higher compared to never-smokers. Additionally, we found that both DPP4 mRNA and protein expression were inversely correlated with lung function and diffusing capacity parameters. Conclusions: We provide evidence that DPP4 is upregulated in the lungs of smokers and COPD patients, which could partially explain why these individuals are more susceptible to MERS-CoV infection. These data also highlight a possible role of DPP4 in COPD pathogenesis.

Clinical management of respiratory syndrome in patients hospitalized for suspected Middle East respiratory syndrome coronavirus infection in the Paris area from 2013 to 2016.

BACKGROUND: Patients with suspected Middle East respiratory syndrome coronavirus (MERS-CoV) infection should be hospitalized in isolation wards to avoid transmission. This suspicion can also lead to medical confusion and inappropriate management of acute respiratory syndrome due to causes other than MERS-CoV. METHODS: We studied the characteristics and outcome of patients hospitalized for suspected MERS-CoV infection in the isolation wards of two referral infectious disease departments in the Paris area between January 2013 and December 2016. RESULTS: Of 93 adult patients (49 male (52.6%), median age 63.4 years) hospitalized, 82 out of 93 adult patients had returned from Saudi Arabia, and 74 of them were pilgrims (Hajj). Chest X-ray findings were abnormal in 72 (77%) patients. The 93 patients were negative for MERS-CoV RT-PCR, and 70 (75.2%) patients had documented infection, 47 (50.5%) viral, 22 (23.6%) bacterial and one Plasmodium falciparum malaria. Microbiological analysis identified Rhinovirus (27.9%), Influenza virus (26.8%), Legionella pneumophila (7.5%), Streptococcus pneumoniae (7.5%), and non-MERS-coronavirus (6.4%). Antibiotics were initiated in 81 (87%) cases, with two antibiotics in 63 patients (67.7%). The median duration of hospitalization and isolation was 3 days (1-33) and 24 h (8-92), respectively. Time of isolation decreased over time (P < 0.01). Two patients (2%) died. CONCLUSION: The management of patients with possible MERS-CoV infection requires medical facilities with trained personnel, and rapid access to virological results. Empirical treatment with neuraminidase inhibitors and an association of antibiotics effective against S. pneumoniae and L. pneumophila are the cornerstones of the management of patients hospitalized for suspected MERS-CoV infection.

The use of complementary and alternative medicine by patients with cancer: a cross-sectional survey in Saudi Arabia.

BACKGROUND: A significant proportion of cancer patients use complementary and alternative medicine (CAM) along with conventional therapies (CT), whereas a smaller proportion delay or defer CT in favor of CAM. Previous studies exploring CAM use among cancer patients in the Middle East region have shown discrepant results. This study investigates the prevalence and pattern of CAM use by Saudi cancer patients. It also discusses the possible benefits and harm related to CAM use by cancer patients, and it explores the beliefs patients hold and their transparency with health care providers regarding their CAM use. METHODS: A cross-sectional study was conducted in oncology wards and outpatient clinics by using face-to-face interviews with the participants. RESULTS: A total of 156 patients with a median age of 50 years (18-84) participated in the study. The prevalence of CAM use was 69.9%; the most prominent types of CAM were those of a religious nature, such as supplication (95.4%), Quran recitation (88.1%), consuming Zamzam water (84.4%), and water upon which the Quran has been read (63.3%). Drinking camel milk was reported by 24.1% of CAM users, whereas camel urine was consumed by 15.7%. A variety of reasons were given for CAM use: 75% reported that they were using CAM to treat cancer, enhance mood (18.3%),control pain (11.9%), enhance the immune system (11%),increase physical fitness (6.4%), and improve appetite (4.6%). Thirty percent of CAM users had discussed the issue with their doctors; only 7.7% had done so with their nurses. CONCLUSIONS: The use of CAM, including camel products, is highly prevalent among cancer patients in the Middle East, but these patients do not necessarily divulge their CAM use to their treating physicians and nurses. Although CAM use can be beneficial, some can be very harmful, especially for cancer patients. Association is known between camel products and brucellosis and Middle East respiratory syndrome coronavirus (MERS-CoV). Both can lead to tremendous morbidity in immune-compromised patients. Doctor-patient communication regarding CAM use is of paramount importance in cancer care.

No MERS-CoV but positive influenza viruses in returning Hajj pilgrims, China, 2013-2015.

BACKGROUND: There is global health concern that the mass movement of pilgrims to and from Mecca annually could contribute to the international spread of Middle East Respiratory Syndrome Coronavirus (MERS-CoV). In China, about 11,000 Muslim pilgrims participate in the Hajj gathering in Mecca annually. This is the first report of MERS-CoV and respiratory virus molecular screening of returning pilgrims at points of entry in China from 2013 to 2015. METHODS AND RESULTS: A total of 847 returning Hajj pilgrims participated in this study. The test results indicated that of the travelers, 34 tested positive for influenza A virus, 14 for influenza B virus, 4 for metapneumo virus, 2 for respiratory syncytial virus, and 3 for human coronavirus. There was a significant difference in the rates of positive and negative influenza virus tests between Hajj pilgrims with symptoms and those without. The detection rates of influenza virus were not significantly different among the three years studied, at 5.3, 6.0 and 6.3% for 2013, 2014 and 2015, respectively. DISCUSSION AND CONCLUSION: The MERS-CoV and respiratory viruses detection results at points of entry in China from 2013 to 2015 indicated that there were no MERS-CoV infection but a 5.7% positive influenza viruses in returning Chinese pilgrims.

Feasibility of a randomized controlled trial to assess treatment of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection in Saudi Arabia: a survey of physicians.

BACKGROUND: The Middle East Respiratory Syndrome coronavirus (MERS-CoV) is an emerging respiratory pathogen with a high mortality rate and no specific treatments available to date. The purpose of this study was to determine the feasibility of conducting a randomized controlled trial (RCT) of convalescent plasma therapy for MERS-CoV-infected patients by using MERS-CoV-specific convalescent plasma obtained from previously recovered patients. METHODS: A survey was adapted from validated questionnaire originally aimed to measure network capacities and capabilities within the International Severe Acute Respiratory and emerging Infection Consortium (ISARIC). The questionnaire was modified for this study to include 26 items that were divided into three main domains of interest: (1) the ability to care for critically ill MERS-CoV patients; (2) laboratory capacity to diagnose MERS-CoV and blood bank ability to prepare convalescent plasma; and (3), research capacity to conduct randomized controlled trials. The questionnaire was emailed to physicians. RESULTS: Of 582 physicians who were invited to the survey, 327 responded (56.2 %). The professional focus of the majority of respondents was critical care (106/249 (43 %)), pediatrics (59/249, (24 %)) or internal medicine (52/249 (21 %)) but none was blood banking. Nearly all respondents (251/263 (95 %)) reported to have access to ICU facilities within their institutions. Most respondents (219/270 (81 %)) reported that intensivists were the most physician group responsible for treatment decisions about critically ill SARI patients. While 125/165 respondents (76 %) reported that they conduct research in ICUs, and 80/161 (49.7 %) had been involved in the conduct of RCTs, including using a placebo comparison (60/161 (37 %)), only 49/226 (21 %) of respondents regularly participated in research networks. CONCLUSIONS: Our survey indicated that in the Kingdom of Saudi Arabia (KSA), ICUs are the most likely clinical locations for conducting a clinical trial of convalescent plasma therapy for MERS-CoV, and that most ICUs have experience with such research designs.

Acute Middle East Respiratory Syndrome Coronavirus: Temporal Lung Changes Observed on the Chest Radiographs of 55 Patients.

OBJECTIVE: The objective of our study was to describe lung changes on serial chest radiographs from patients infected with the acute Middle East respiratory syndrome corona-virus (MERS-CoV) and to compare the chest radiographic findings and final outcomes with those of health care workers (HCWs) infected with the same virus. Chest radiographic scores and comorbidities were also examined as indicators of a fatal outcome to determine their potential prognostic value. MATERIALS AND METHODS: Chest radiographs of 33 patients and 22 HCWs infected with MERS-CoV were examined for radiologic features indicative of disease and for evidence of radiographic deterioration and progression. Chest radiographic scores were estimated after dividing each lung into three zones. The scores (1 [mild] to 4 [severe]) for all six zones per chest radiographic examination were summed to provide a cumulative chest radiographic score (range, 0-24). Serial radiographs were also examined to assess for radiographic deterioration and progression from type 1 (mild) to type 4 (severe) disease. Multivariate logistic regression analysis, Kaplan-Meier survival curve analysis, and the Mann-Whitney U test were used to compare data of deceased patients with those of individuals who recovered to identify prognostic radiographic features. RESULTS: Ground-glass opacity was the most common abnormality (66%) followed by consolidation (18%). Overall mortality was 35% (19/55). Mortality was higher in the patient group (55%, 18/33) than in the HCW group (5%, 1/22). The mean chest radiographic score for deceased patients was significantly higher than that for those who recovered (13 ± 2.6 [SD] vs 5.8 ± 5.6, respectively; p = 0.001); in addition, higher rates of pneumothorax (deceased patients vs patients who recovered, 47% vs 0%; p = 0.001), pleural effusion (63% vs 14%; p = 0.001), and type 4 radiographic progression (63% vs 6%; p = 0.001) were seen in the deceased patients compared with those who recovered. Univariate and logistic regression analyses identified the chest radiographic score as an independent predictor of mortality (odds ratio [OR], 1.38; 95% CI, 1.07-1.77; p = 0.01). The number of comorbidities in the patient group (n = 33) was significantly higher than that in the HCW group (n = 22) (mean number of comorbidities, 1.90 ± 1.27 vs 0.17 ± 0.65, respectively; p = 0.001). The Kaplan-Meier analysis revealed a median survival time of 15 days (95% CI, 4-26 days). CONCLUSION: Ground-glass opacity in a peripheral location was the most common abnormality noted on chest radiographs. A higher chest radiographic score coupled with a high number of medical comorbidities was associated with a poor prognosis and higher mortality in those infected with MERS-CoV. Younger HCWs with few or no comorbidities had a higher survival rate.

[Etiological, epidemiological and clinical aspects of coronavirus infection MERS-CoV]. / Etiologiczne, epidemiologiczne i kliniczne aspekty zakazenia koronawirusem MERS-CoV.

All medical staff and travellers to the Arabian Peninsula should be aware of a new epidemic caused by Middle East respiratory syndrome coronavirus (MERS-CoV), which has emerged in the Arabian Peninsula (2012), secondary cases have been seen in Africa, Europe, Asia and the United States. It seems likely that the outbreak will continue with sporadic adventive cases occurring outside the Middle East, including Poland. Polish medical literature on MERS-CoV is rather scant. Therefore, the article describes etiology, epidemiology, symptoms and diagnostic methods of MERS-CoV infection which are available in Poland. Selected cases of patients infected with MERS-CoV are also presented followed by preventive methods. Comparisons between MERS-CoV and SARS-CoV are briefly described. Epidemiological and genetic studies point at zoonotic transmission of MERS-CoV from camels and possibly bats. Infection is characterized by severe acute respiratory failure with a high fatality rate and the ability to spread from person to person; health care-associated outbreaks have been described. No known vaccine or antiviral therapy has been developed for MERS. The diagnosis is made by demonstrating the MERS-CoV in lower respiratory secretions by RT PCR. General hygiene measures such as regular hand washing before and after touching animals and avoiding contact with sick animals in the epidemic areas, should be adhered to. Health-care workers should always apply standard precautions consistently with all patients, regardless of their diagnosis due to non-specific symptoms of MERS-CoV in the early stage of infection.

Enhanced antiviral immunity and dampened inflammation in llama lymph nodes upon MERS-CoV sensing: bridging innate and adaptive cellular immune responses in camelid reservoirs.

Middle East respiratory syndrome coronavirus (MERS-CoV) infection can cause fatal pulmonary inflammatory disease in humans. Contrarily, camelids and bats are the main reservoir hosts, tolerant for MERS-CoV replication without suffering clinical disease. Here, we isolated cervical lymph node (LN) cells from MERS-CoV convalescent llamas and pulsed them with two different viral strains (clades B and C). Viral replication was not supported in LN, but a cellular immune response was mounted. Reminiscent Th1 responses (IFN-γ, IL-2, IL-12) were elicited upon MERS-CoV sensing, accompanied by a marked and transient peak of antiviral responses (type I IFNs, IFN-λ3, ISGs, PRRs and TFs). Importantly, expression of inflammatory cytokines (TNF-α, IL-1ß, IL-6, IL-8) or inflammasome components (NLRP3, CASP1, PYCARD) was dampened. The role of IFN-λ3 to counterbalance inflammatory processes and bridge innate and adaptive immune responses in camelid species is discussed. Our findings shed light into key mechanisms on how reservoir species control MERS-CoV in the absence of clinical disease.

Occupational Health Hazards Among Veterinarians in Saudi Arabia.

Introduction Veterinarians and other professionals who interact with animals on a daily basis encounter an elevated risk of exposure to both known and as-yet-undiscovered microbial agents. Additionally, they are also exposed to physical, chemical, and environmental hazards. Enhancing occupational health and safety in this context carries significant global significance. Methods This study aimed to comprehensively identify and outline the various biological, physical, chemical, and environmental health threats that were encountered by veterinarians in Saudi Arabia. To achieve this, we designed a self-completed questionnaire for 529 participants. The survey encompassed potential occupational hazards such as microbial diseases, injuries resulting from animal bites and scratches, allergies, and environmental risks like sunstroke and dust storms. Results Among the 529 participating veterinarians, 45.9% (243 individuals) reported instances of zoonotic diseases within the past five years. Notably, potential viral agents included Middle East respiratory syndrome coronavirus, avian influenza, and foot-and-mouth disease virus. Bacterial diseases were also frequently documented, with brucellosis (18.7%) and salmonellosis (7.9%) being notable pathogens. Protozoal infections were led by Leishmaniosis, constituting the most commonly detected protozoa (29 /529, 5.5%). Interestingly, 345 (65.2%) of the individuals reported that they have experienced animal bites and scratches. Needle stick injuries were also a common occupational hazard, with an incidence rate of 19.1%. Additionally, chemical exposure was prevalent, particularly to disinfectants (57.5%) and veterinary drugs (23.4%). The study participants also reported their exposure to various environmental hazards, including sunstroke, dust, sandstorms, and heavy rains. Conclusion The findings of this study draw attention to a concerning trend among veterinarians in Saudi Arabia. Their personal health and safety appear to receive inadequate attention, potentially heightening the risk of occupationally related health hazards. These outcomes highlight the need for a reevaluation of safety protocols and infection control practices within the veterinary profession. The implications of this study can potentially inform the development of policies and initiatives aimed at mitigating occupationally related health hazards among veterinarians in Saudi Arabia.

Respiratory virus detection in returning travelers and pilgrims from the Middle East.

BACKGROUND: Pilgrims travelling to Saudi Arabia are commonly infected with respiratory viruses. Since the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) emerged in 2012, patients with acute respiratory symptoms returning from an endemic area can be suspected to be infected by this virus. METHODS: 98 patients suspected to have MERS-CoV infection from 2014 to 2019 were included in this retrospective cohort study. Upper and lower respiratory tract samples were tested by real-time RT-PCR for the detection of MERS-CoV and other respiratory viruses. Routine microbiological analyses were also performed. Patient data were retrieved from laboratory and hospital databases retrospectively. RESULTS: All patients with suspected MERS-CoV infection travelled before their hospitalization. Most frequent symptoms were cough (94.4%) and fever (69.4%). 98 specimens were tested for MERS-CoV RNA and none of them was positive. Most frequently detected viruses were Enterovirus/Rhinovirus (40/83; 48.2%), Influenzavirus A (34/90; 37.8%) and B (11/90; 12.2%), H-CoV (229E and OC43 10/83; 12% and 7/83; 8.4%, respectively). CONCLUSION: From 2014 to 2019, none of 98 patients returning from endemic areas was MERS-CoV infected. However, infections with other respiratory viruses were frequent, especially with Enterovirus/Rhinoviruses and Influenzaviruses.

Middle East Respiratory Syndrome coronavirus vaccine development: updating clinical studies using platform technologies.

Middle East Respiratory Syndrome coronavirus (MERS-CoV), a contagious zoonotic virus, causes severe respiratory infection with a case fatality rate of approximately 35% in humans. Intermittent sporadic cases in communities and healthcare facility outbreaks have continued to occur since its first identification in 2012. The World Health Organization has declared MERS-CoV a priority pathogen for worldwide research and vaccine development due to its epidemic potential and the insufficient countermeasures available. The Coalition for Epidemic Preparedness Innovations is supporting vaccine development against emerging diseases, including MERS-CoV, based on platform technologies using DNA, mRNA, viral vector, and protein subunit vaccines. In this paper, we review the usefulness and structure of a spike glycoprotein as a MERS-CoV vaccine candidate molecule, and provide an update on the status of MERS-CoV vaccine development. Vaccine candidates based on both DNA and viral vectors coding MERS-CoV spike gene have completed early phase clinical trials. A harmonized approach is required to assess the immunogenicity of various candidate vaccine platforms. Platform technologies accelerated COVID-19 vaccine development and can also be applied to developing vaccines against other emerging viral diseases.

Middle East respiratory syndrome coronavirus (MERS-CoV) infection: Analyses of risk factors and literature review of knowledge, attitude and practices.

The study aimed to explore the risk factors for MERS-CoV infection and systematic review of knowledge, attitudes and practices (KAP) with regard to MERS-CoV among the health care workers (HCWs) and the general population. The World Health Organization's MERS-CoV line list (January 2013-January 2020) of the Kingdom of Saudi Arabia (KSA) was analysed. A Poisson regression model was used to calculate the univariate relative risk of outcomes to each potential risk factor, p-values and 95% confidence intervals. An electronic literature search was conducted to assess knowledge, attitudes and practices of the HCWs and general population of the KSA, with regards to transmission of the infection, risk factors and preventative measures. The line list analysis shows that age, gender, comorbidity, exposure to camels and camel milk consumption were associated with an increased risk of fatality; however, year-wise analysis did not show any decline. Over the years, the mean durations between the symptom onset and hospitalization; the hospitalization and laboratory confirmation have reduced. The review of literature shows that the health care workers and the general population had inadequate knowledge about MERS-CoV, lacked motivation and were disconnected from the health authorities. The WHO line list provides information on risk factors for MERS-CoV, KAP analysis helps to know the potential underlying factors. The literature review shows that continuous education for HCWs and increasing public awareness can help effectively manage future MERS-CoV.

Review of Thoracic Imaging Manifestations of COVID-19 and Other Pathologic Coronaviruses.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an easily transmissible coronavirus that emerged in late 2019 and has caused a global pandemic characterized by acute respiratory disease named coronavirus disease 2019 (COVID-19). Diagnostic imaging can be helpful as a complementary tool in supporting the diagnosis of COVID-19 and identifying alternative pathology. This article presents an overview of acute and postacute imaging findings in COVID-19.

Development of virus-like particles-based vaccines against coronaviruses.

Severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are the most impactful coronaviruses in human history, especially the latter, which brings revolutionary changes to human vaccinology. Due to its high infectivity, the virus spreads rapidly throughout the world and was declared a pandemic in March 2020. A vaccine would normally take more than 10 years to be developed. As such, there is no vaccine available for SARS-CoV and MERS-CoV. Currently, 10 vaccines have been approved for emergency use by World Health Organization (WHO) against SARS-CoV-2. Virus-like particle (VLP)s are nanoparticles resembling the native virus but devoid of the viral genome. Due to their self-adjuvanting properties, VLPs have been explored extensively for vaccine development. However, none of the approved vaccines against SARS-CoV-2 was based on VLP and only 4% of the vaccine candidates in clinical trials were based on VLPs. In the current review, we focused on discussing the major advances in the development of VLP-based vaccine candidates against the SARS-CoV, MERS-CoV, and SARS-CoV-2, including those in clinical and pre-clinical studies, to give a comprehensive overview of the VLP-based vaccines against the coronaviruses.

C1 esterase inhibitor-mediated immunosuppression in COVID-19: Friend or foe?

From asymptomatic to severe, SARS-CoV-2, causative agent of COVID-19, elicits varying disease severities. Moreover, understanding innate and adaptive immune responses to SARS-CoV-2 is imperative since variants such as Omicron negatively impact adaptive antibody neutralization. Severe COVID-19 is, in part, associated with aberrant activation of complement and Factor XII (FXIIa), initiator of contact system activation. Paradoxically, a protein that inhibits the three known pathways of complement activation and FXIIa, C1 esterase inhibitor (C1-INH), is increased in COVID-19 patient plasma and is associated with disease severity. Here we review the role of C1-INH in the regulation of innate and adaptive immune responses. Additionally, we contextualize regulation of C1-INH and SERPING1, the gene encoding C1-INH, by other pathogens and SARS viruses and propose that viral proteins bind to C1-INH to inhibit its function in severe COVID-19. Finally, we review the current clinical trials and published results of exogenous C1-INH treatment in COVID-19 patients.