Impact of MERS-CoV and SARS-CoV-2 Viral Infection on Immunoglobulin-IgG Cross-Reactivity.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has posed a considerable threat to public health and global economies. SARS-CoV-2 has largely affected a vast world population and was declared a COVID-19 pandemic outbreak, with a substantial surge of SARS-CoV-2 infection affecting all aspects of the virus' natural course of infection and immunity. The cross-reactivity between the different coronaviruses is still a knowledge gap in the understanding of the SARS-CoV-2 virus. This study aimed to investigate the impact of MERS-CoV and SARS-CoV-2 viral infections on immunoglobulin-IgG cross-reactivity. Our retrospective cohort study hypothesized the possible reactivation of immunity in individuals with a history of infection to Middle East Respiratory Syndrome coronavirus (MERS-CoV) when infected with SARS-CoV-2. The total number of participants included was 34; among them, 22 (64.7%) were males, and 12 (35.29%) were females. The mean age of the participants was 40.3 ± 12.9 years. This study compared immunoglobulin (IgG) levels against SARS-CoV-2 and MERS-CoV across various groups with various histories of infection. The results showed that a reactive borderline IgG against both MERS-CoV and SARS-CoV-2 in participants with past infection to both viruses was 40% compared with 37.5% among those with past infection with MERS-CoV alone. Our study results establish that individuals infected with both SARS-CoV-2 and MERS-CoV showed higher MERS-CoV IgG levels compared with those of individuals infected previously with MERS-CoV alone and compared with those of individuals in the control. The results further highlight cross-adaptive immunity between MERS-CoV and SARS-CoV. Our study concludes that individuals with previous infections with both MERS-CoV and SARS-CoV-2 showed significantly higher MERS-CoV IgG levels compared with those of individuals infected only with MERS-CoV and compared with those of individuals in the control, suggesting cross-adaptive immunity between MERS-CoV and SARS-CoV.

Assessment of Proinflammatory Cytokines Among Patients with Middle East Respiratory Syndrome Coronavirus Infection.

Middle East respiratory syndrome coronavirus (MERS-CoV) is associated with significant morbidity and mortality. This study was performed to assess the proinflammatory cytokines profile among MERS-CoV patients. A total of 46 MERS-CoV-infected patients (27 symptomatic and 19 asymptomatic) were assessed and compared with 52 normal healthy controls for plasma levels of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-17, IL-7, IL-6, interferon (IFN)-α, and IL-15 using a customized luminex kit. Whereas asymptomatic MERS-CoV patients and controls were no different; the mean plasma levels among MERS-CoV symptomatic patients were significantly higher than the normal controls: IL-1ß (16.89 ± 1.23 vs. 12.80 ± 0.59 pg/mL; p < 0.001), TNF-α (14.04 ± 0.93 vs. 10.35 ± 0.29 pg/mL; p < 0.0001), IL-17 (14.3 ± 0.89 vs. 11.47 ± 0.61 pg/mL; p < 0.001), IL-7 (21.56 ± 1.00 vs. 16.31 ± 0.30 pg/mL; p < 0.0001), IL-6 (156.5 ± 37.90 vs. 18.60 ± 1.59 pg/mL; p < 0.0001), and IFN-α (68.73 ± 13.06 vs. 23.57 ± 1.05 pg/mL; p < 0.0001). The mean plasma levels of IL-7 (24.81 ± 1.63 vs. 19.79 ± 0.94 pg/mL; p < 0.01), IL-6 (312.7 ± 94.67 vs. 101.2 ± 25.67 pg/mL; p < 0.01), and IFN-α (89.00 ± 18.97 vs. 51.05 ± 8.68 pg/mL; p < 0.05) were significantly elevated among MERS-CoV symptomatic patients with fatal outcome compared with MERS-CoV symptomatic patients who survived. Only IL-7 was found to have a higher risk ratio of mortality (4.76, 95% confidence interval: 1.5-14.94; p < 0.01). No differences were observed in IL-15 levels among the groups. Significantly elevated proinflammatory cytokines among symptomatic MERS-CoV-infected patients may contribute to manifestations of cytokine storm frequently observed among critically ill MERS-CoV patients and IL-7 may serve as a marker for disease activity.

Differential expression of carcinoembryonic antigen-related cell adhesion molecule-5 (CEACAM5) and dipeptidyl peptidase-4 (DPP4) with detection of Middle East respiratory syndrome-coronavirus in peripheral blood.

BACKGROUND: Middle East respiratory syndrome-coronavirus (MERS-CoV) utilizes CD26 (dipeptidyl peptidase-4) and CD66e or CEACAM5 (carcinoembryonic antigen-related cell adhesion molecule 5) receptors for cell infection. Peripheral blood mononuclear cells (PBMCs) play a critical role in mounting adaptive immune response against the virus. This study was performed to assess the expression of CD26 and CD66e on PBMCs and their susceptibility to MERS-CoV infection. METHODS: Surface expression of CD26 and CD66e receptors on PBMCs from MERS-CoV patients (n = 20) and healthy controls (n = 20) was assessed by flow cytometry and the soluble forms were determined by enzyme-linked immunosorbent assay (ELISA). MERS-CoV UpE and Orf1a genes in PBMCs were detected by using Altona diagnostics reverse transcription polymerase chain reaction (RT-PCR) kit. RESULTS: Mean fluorescent intensity (MFI) of CD66e was significantly higher on CD4 + lymphocytes (462.4 ± 64.35 vs 325.1 ± 19.69; p < 0.05) and CD8 + lymphocytes (533.8 ± 55.32 vs 392.4 ± 37.73; p < 0.04) from patients with MERS-CoV infection compared to the normal controls. No difference in MFI for CD66e was observed on monocytes (381.8 ± 40.34 vs 266.8 ± 20.6; p = 0.3) between the patients and controls. Soluble form of CD66e among MERS-CoV patients was also higher than the normal controls (mean= 338.7 ± 58.75 vs 160.7 ± 29.49 ng/mL; p < 0.01). Surface expression of CD26 on PBMCs and its soluble form were no different between the groups. MERS-CoV was detected by RT-PCR in 16/20 (80%) patients from whole blood, among them 8 patients were tested in PBMCs, 4/8 (50%) patients were positive. CONCLUSION: Increased expression levels of CD66e (CEACAM5) may contribute to increased susceptibility of PBMCs to MERS-CoV infection and disease progression.

The short-term effect of different chlorhexidine forms versus povidone iodine mouth rinse in minimizing the oral SARS-CoV-2 viral load: An open label randomized controlled clinical trial study.

Several investigations evaluated the possibility of different types of mouth wash rinse in minimizing the SARS-CoV-2 load. However, results still controversial. The study aim is to assess the short-term efficiency of several over-the-counter mouth rinses and lozenges in minimizing the salivary viral load for SARS-CoV-2 in patients with confirmed COVID-19 in comparison to saline. This is a randomized controlled clinical trial with 4 arms. The recruited cases were randomized using a simple randomization technique and were assigned to chlorhexidine digluconate mouth rinse (CHX mouth rinse), 2 mg of chlorhexidine digluconate lozenges (CHX lozenges), povidone iodine mouth rinse (PVP-I mouth rinse) or saline as a control group. Saliva were collected from all study subjects by passive drool technique at two time points. First, prior to intervention with mouth rinse or the lozenges, the baseline saliva sample was collected. Second saliva samples were collected immediately after the mouth rinse. Real time PCR was conducted and the value threshold cycle (Ct) for each sample was recorded. Majority of the participants had an education level of high school or less (60%), were married (68.3), males (58.3%), and non-smokers (58.5%). No statistically significant differences between groups at the two times test (P > .05). However, a significant decrease of salivary viral load in all four groups combined (P-value for E genes = .027, and for S genes = .006), and in PVP-I mouth rinse specifically (P = .003 and P = .045, respectively). Povidone iodine mouth rinse showed a potential influence on the reduction of the viral load on a short-term basis. However, longer-term studies of the effect of these products should be conducted.

Possible vertical transmission of corona virus disease 19 (COVID-19) from infected pregnant mothers to neonates: a multicenter study.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly contagious with various possible routes of transmission, resulting in high mortality globally. Controversy exists regarding the vertical transmission of the SARS-CoV-2 infection to fetuses of COVID-19-infected women. The aim of this study was to investigate the possibility of the vertical transmission of SARS-CoV-2 from COVID-19-infected mothers to their neonates. MATERIALS AND METHODS: We prospectively collected demographical and clinical characteristics of 31 COVID-19 positive pregnant women and their neonates. All mothers and neonates were tested for SARS-CoV-2 infection using the real-time polymerase chain reaction on nasopharyngeal swabs and breast milk samples. Antenatal and placental abnormalities were ultrasonically and histopathologically examined. In cord blood samples, the immunoglobins (Ig) M and IgG were estimated qualitatively. RESULTS: The women's mean age and gestational age were 31 years and 38 weeks, respectively, with 58% undergoing an elective cesarean section. Gestational diabetes was reported in 29% of cases, 64.5% of women were medically free and only 16.12% were symptomatic. A normal antenatal ultrasound was observed in 77.42% of cases. Nine cord blood samples were positive for IgG. Villous infarction (24%), villous agglutination, and chorangiosis (51%), accelerated villous maturation (21%) and reduced and hypercoiling were reported for 6.97% of the umbilical cords. Three newborns had possible vertical transmission of SARS-CoV-2 infection, of which, two were preterm and IUFD. The third neonate was born full-term, admitted to NICU and later discharged in good health. CONCLUSION: Our findings support the possibility of the direct vertical transmission of the SARS-CoV-2 infection to neonates from infected mothers. Further studies with a larger sample size are required to validate the current findings.

Can periodontal pockets and caries lesions act as reservoirs for coronavirus?

The periodontal pocket and likely caries lesions may act as a reservoir and source of dissemination and development of systemic infections. While periodontal pockets have been found to harbor several viral species, there is no information on its ability to serve as a reservoir for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We have used a real-time polymerase chain reaction (RT-PCR) approach to evaluate SARS-CoV-2 in periodontal pockets and cavitated caries lesions in a cross-sectional study of 72 participants who were divided into six groups: symptomatic positive COVID-19 cases with periodontal pockets, symptomatic positive with cavitated caries lesions, asymptomatic positive with periodontal pockets, asymptomatic positive with cavitated caries lesions, positive control, and negative control. A total of 180 samples were interrogated by RT-PCR to amplify the SARS-CoV-2 E and S genes. SARS-CoV-2 was present in 41.7% of symptomatic positive COVID-19 cases with periodontal pockets and 16.7% of symptomatic positive with cavitated caries lesions. The mean Ct value of E and S genes in periodontal pockets patients were 36.06±0.46 and 30.06±6.73, respectively, and the mean Ct value for both genes in caries lesions patients were 35.73±4.14, and 34.78±1.93, respectively. The sensitivity, specificity, and accuracy to detect SARS-CoV-2 among periodontal pockets were 20.8% (95% CI 7.13-42.15), 100% (95% CI 73.54-100.0), and 47.2% (95% CI 30.22-64.51), respectively. Among cavitated caries lesions patients, they were 8.3% (95% CI 1.03-27.0), 100% (95% CI 73.54-100.0), and 38.9% (95% CI 23.14-56.54), respectively. SARS-CoV-2 can be detected in periodontal pockets and caries lesions, and these sites may act as reservoirs for the virus. However, the sensitivity of SARS-CoV-2 detection is low compared with other methods. To our knowledge, this report is the first to investigate the relationship between SARS-CoV-2 and periodontal pockets and caries.

Risk factors and predictors that influence SARS-Cov-2 IgG positivity: A cross-sectional study of blood donors in Riyadh, Saudi Arabia.

OBJECTIVES: To study the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after pandemic's peak and before the vaccine enrollment in Riyadh, Saudi Arabia and further explore predictors for SARS-CoV-2 positivity. METHODS: A cross-sectional study of 515 blood donors from November 22 to December 17, 2020 was conducted at King Saud University Medical City, Riyadh, Saudi Arabia to look at SARS-CoV-2 immunoglobulin G (IgG) positivity. The participants were asked questions about their demographic characteristics, past SARS-CoV-2 infection, SARS-CoV-2-related symptoms and exposures. RESULTS: The seroprevalence in our study was 12.2% (n=63/515). Being a non-citizen was associated with significantly higher seroprevalence (OR 2.10, p=0.02). Participants with history of SARS-CoV-2 exposure or symptoms regardless of SARS-CoV-2 diagnosis had higher SARS-CoV-2 IgG positivity compared to unexposed or asymptomatic participants (OR 2.47, p=0.0008 or 11.19, p=0.0001, respectively). Blood donors who had symptomatic SARS-CoV-2 IgG infection had a higher SARS-CoV-2 IgG positivity rate (OR 5.04, p=0.008) and index value (p=0.003) than the asymptomatic. Of all the reported symptoms, cough (p=0.004) and anosmia (p=0.002) were significant predictors of SARS-CoV-2 IgG. CONCLUSION: The seroprevalence of SARS-CoV-2 among the blood donors in Riyadh, Saudi Arabia is considerably lower than the percentages necessary for herd immunity. Developing SARS-CoV-2-symptoms is the critical factor for higher seropositivity after SARS-CoV-2 exposure.

Clinical characteristics and outcomes of hospitalized COVID-19 patients in a MERS-CoV referral hospital during the peak of the pandemic.

OBJECTIVE: To describe the clinical characteristics and outcomes of hospitalized coronavirus disease 2019 (COVID-19) patients in a middle east respiratory syndrome coronavirus (MERS-CoV) referral hospital during the peak months of the pandemic. DESIGN: A single-center case series of hospitalized individuals with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in King Saud University Medical City (KSUMC), an academic tertiary care hospital in Riyadh, Saudi Arabia. Clinical and biochemical markers were documented. Risks for ventilatory support, intensive care unit (ICU) admission and death are presented. RESULTS: Out of 12,688 individuals tested for SARS-CoV-2 by real time reverse transcriptase polymerase reaction (RT-PCR) from June 1 to August 31, 2020, 2,683 (21%) were positive for COVID-19. Of the latter, 605 (22%) patients required hospitalization with a median age of 55, 368 (61%) were male. The most common comorbidities were hypertension (43%) and diabetes (42%). Most patients presented with fever (66%), dyspnea (65%), cough (61%), elevated IL-6 (93.5%), D-dimer (90.1%), CRP (86.1%), and lymphopenia (41.7%). No MERS-CoV co-infection was detected. Overall, 91 patients (15%) died; risk factors associated with mortality were an age of 65 years or older OR 2.29 [95%CI 1.43-3.67], presence of two or more comorbidities OR 3.17 [95%CI 2.00-5.02], symptoms duration of seven days or less OR 3.189 [95%CI (1.64 - 6.19]) lymphopenia OR 3.388 [95%CI 2.10-5.44], high CRP OR 2.85 [95%CI 1.1-7.32], high AST OR 2.95 [95%CI 1.77-4.90], high creatinine OR 3.71 [95%CI 2.30-5.99], and high troponin-I OR 2.84 [95%CI 1.33-6.05]. CONCLUSION: There is a significant increase in severe cases of COVID-19. Mortality was associated with older age, shorter symptom duration, high CRP, low lymphocyte count, and end-organ damage.

Clinical Characteristics and Outcome of Hospitalized COVID-19 Patients in a MERS-CoV Endemic Area.

BACKGROUND: The Kingdom of Saudi Arabia (KSA) reported 170,639 cases and 1430 deaths from COVID-19 since the first case emerged in the country on March 2 through June 25, 2020. The objective of this report is to describe the characteristics and outcome observed among 99 hospitalized COVID-19 patients in the largest academic hospital in KSA, and assess co-infection with the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). METHODS: This single-center case series data included select epidemiological, clinical, radiological features and laboratory findings of all confirmed hospitalized cases of COVID-19 in King Saud University Medical City (KSUMC), Riyadh, KSA, from March 22 until May 31, 2020, followed through June 6, 2020. We conducted retrospective analysis of listed data from 99 hospitalized patients and present characteristics and factors associated with severity in percentages and univariate odds ratios. Cases were confirmed using nasopharyngeal or throat swab by real-time Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and MERS-CoV by RT-PCR. RESULTS: The 99 hospitalized COVID-19 patients included in this analysis constitute 16% of 632 positive SARS-CoV-2 among 6633 persons who were tested at the KSUMC (positivity rate, 9.4%). MERS-CoV PCR was negative in all 99 patients tested. The majority of these 99 hospitalized patients were males (66%), had a mean age of 44 years (range, 19-87), and a quarter (25.3%) were health care workers. Patients with comorbid conditions accounted for 52.5% of patients including the 8.1% who were asymptomatic; diabetes mellitus being the most frequent (31.3%), followed by hypertension (22.2%). The most common presenting symptoms were fever (67.7%), cough (60.6%), dyspnea (43.4%), upper respiratory symptoms (27.3%), fatigue (26.3%), diarrhea (19.2%) and loss of smell (9.1%). The clinical conditions among these 99 patients included upper respiratory tract infection (47.5%), abnormal chest X-ray, lymphopenia, high inflammatory markers a fifth (21%) of patients had moderate pneumonia, while 7% had severe pneumonia with 22.2% requiring admission to the intensive care unit and 12.1% died. Late presentation with severe disease, an abnormal chest X-ray, lymphopenia, high inflammatory markers (C-reactive protein, ferritin, and procalcitonin), and end organ damage (high creatinine or high aspartate aminotransferase) were predictors for admission to critical care unit or died. CONCLUSION: We observed no MERS-CoV co-infection in this early cohort of hospitalized COVID-19 patients who were relatively young, more than half had comorbid conditions, presented with fever and/or cough, an abnormal chest X-ray, lymphopenia, and high inflammatory markers. Given MERS-CoV endemicity in the country, co-monitoring of MERS-CoV and SARS-CoV-2 coinfection is critical.