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Three novel human coronaviruses have caused different worldwide outbreaks that had variable disease severity and geographic distribution: severe acute respiratory syndrome coronavirus (SARS-CoV) during 2003; Middle East respiratory syndrome (MERS) [...]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent for coronavirus 2019 (COVID-19) pneumonia. Little is known about the kinetics, tissue distribution, cross-reactivity, and neutralization antibody response in patients with COVID-19. Two groups of patients with RT-PCR-confirmed COVID-19 were enrolled in this study: 12 severely ill patients in intensive care units who needed mechanical ventilation and 11 mildly ill patients in isolation wards. Serial clinical samples were collected for laboratory detection. Results showed that most of the severely ill patients had viral shedding in a variety of tissues for 20-40 days after onset of disease (8/12, 66.7%), while the majority of mildly ill patients had viral shedding restricted to the respiratory tract and had no detectable virus RNA 10 days after onset (9/11, 81.8%). Mildly ill patients showed significantly lower IgM response compared with that of the severe group. IgG responses were detected in most patients in both the severe and mild groups at 9 days after onset, and remained at a high level throughout the study. Antibodies cross-reactive to SARS-CoV and SARS-CoV-2 were detected in patients with COVID-19 but not in patients with MERS. High levels of neutralizing antibodies were induced after about 10 days after onset in both severely and mildly ill patients which were higher in the severe group. SARS-CoV-2 pseudotype neutralization test and focus reduction neutralization test with authentic virus showed consistent results. Sera from patients with COVID-19 inhibited SARS-CoV-2 entry. Sera from convalescent patients with SARS or Middle East respiratory syndrome (MERS) did not. Anti-SARS-CoV-2 S and N IgG levels exhibited a moderate correlation with neutralization titers in patients' plasma. This study improves our understanding of immune response in humans after SARS-CoV-2 infection., Introduction Before November 2019, 6 coronaviruses (CoVs) were known to infect humans and cause respiratory disease: OC43, 229E, HKU1, and NL63, 4 community-acquired CoVs that are endemic in humans (1-4), [...]

The genome of severe acute respiratory coronavirus-2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19), has undergone a rapid evolution, resulting in the emergence of multiple SARS-CoV-2 variants with amino acid changes. This study aimed to sequence the whole genome of SARS-CoV-2 and detect the variants present in specimens from Saudi Arabia. Furthermore, we sought to analyze and characterize the amino acid changes in the various proteins of the identified SARS-CoV-2 variants. A total of 1161 samples from patients diagnosed with COVID-19 in Saudi Arabia, between 1 April 2021 and 31 July 2023, were analyzed. Whole genome sequencing was employed for variant identification and mutation analysis. The statistical analysis was performed using the Statistical Analytical Software SAS, version 9.4, and GraphPad, version 9.0. This study identified twenty-three variants and subvariants of SARS-CoV-2 within the population, with the Omicron BA.1 (21K) variant (37.0%) and the Delta (21J) variant (12%) being the most frequently detected. Notably, the Omicron subvariants exhibited a higher mean mutation rate. Amino acid mutations were observed in twelve proteins. Among these, the spike (S), ORF1a, nucleocapsid (N), and ORF1b proteins showed a higher frequency of amino acid mutations compared to other the viral proteins. The S protein exhibited the highest incidence of amino acid mutations (47.6%). Conversely, the ORF3a, ORF8, ORF7a, ORF6, and ORF7b proteins appeared more conserved, demonstrating the lowest percentage and frequency of amino acid mutations. The investigation of structural protein regions revealed the N-terminal S1 subunit of the S protein to frequently harbor mutations, while the N-terminal domain of the envelope (E) protein displayed the lowest mutation frequency. This study provides insights into the variants and genetic diversity of SARS-CoV-2, underscoring the need for further research to comprehend its genome evolution and the occurrence of mutations. These findings are pertinent to the development of testing approaches, therapeutics, and vaccine strategies. [ABSTRACT FROM AUTHOR]

RNA viruses, including SARS-CoV-2, rely on genetic mutation as a major evolutionary mechanism, leading to the emergence of variants. Organ transplant recipients (OTRs) may be particularly vulnerable to such mutations, making it crucial to monitor the spread and evolution of SARS-CoV-2 in this population. This cohort study investigated the molecular epidemiology of SARS-CoV-2 by comparing the SARS-CoV-2 whole genome, demographic characteristics, clinical conditions, and outcomes of COVID-19 illness among OTRs (n = 19) and non-OTRs with (n = 38) or without (n = 30) comorbid conditions. Most patients without comorbidities were female, whereas most OTRs were male. Age varied significantly among the three groups: patients with comorbidities were the oldest, and patients without comorbidities were the youngest. Whole-genome sequencing revealed that OTRs with mild disease had higher numbers of unusual mutations than patients in the other two groups. Additionally, OTRs who died had similar spike monoclonal antibody resistance mutations and 3CLpro mutations, which may confer resistance to nirmatrelvir, ensitrelvir, and GC37 therapy. The presence of those unusual mutations may impact the severity of COVID-19 illness in OTRs by affecting the virus's ability to evade the immune system or respond to treatment. The higher mutation rate in OTRs may also increase the risk of the emergence of new virus variants. These findings highlight the importance of monitoring the genetic makeup of SARS-CoV-2 in all immunocompromised populations and patients with comorbidity. [ABSTRACT FROM AUTHOR]

Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV), identified in 2012, causes a highly lethal pneumonia with a 34.5% mortality rate (https://www. who.int/emergencies/mers-cov). As of July 31, 2019, a total of [...]

Background: The protozoan parasite Toxoplasma gondii may cause serious illness in the immunocompromised. The Toxoplasma gondii seropositive prevalence in pregnant women in WHO Eastern Mediterranean Region countries is inconsistent in the literature and it is associated with outcomes that have not be fully elucidated, hence the need for a better understanding of the pooled seroprevalence and associated maternal and fetal outcomes. Objective: The objective was to conduct a systematic literature review and determine the pooled prevalence of WHO Eastern Mediterranean Regional countries' pregnant women's seroprevalence of Toxoplasma gondii and the maternal–fetal outcomes. Methods: This quantitative study examined WHO Eastern Mediterranean countries' maternal–fetal outcomes and Toxoplasma gondii prevalence in pregnant women. The targeted population was pregnant women, while the primary outcome was seropositivity of Toxoplasma gondii, while other outcomes such as maternal and fetal associations and risk factors were determined PubMed, SCOPUS, MEDLINE, and Index Medicus for the Eastern Mediterranean Region (IMEMR) databases were searched up until 30 January 2023. The search terms used were "Toxoplasma gondii" OR "Toxoplasma infection" AND "Pregnant woman" or pregnan* OR Antenatal OR Prenatal OR Gravidity OR Parturition OR Maternal AND WHO Eastern Mediterranean Region). OpenMeta-Analyst and Jamovi were used to analyze the generated data. Results: In total, 95 of 2947 articles meeting the inclusion criteria examined Toxoplasma gondii prevalence in pregnant women from WHO Eastern Mediterranean countries. The pooled prevalence of Toxoplasma gondii in pregnant women was 36.5% (95%CI: 32.6–40.4) with a median value of 35.64%, range values of 1.38–75.30%, with 99.61% heterogeneity. The pooled seroprevalence of IgG of Toxoplasma gondii was 33.5% (95%CI: 29.8–37.2) with a median value of 33.51%, and a range values of 1.38–69.92%; the pooled seroprevalence of IgM was 3.6% (95%CI: 3.1–4.1)) with a median value of 3.62 and range values of 0.20–17.47%, while cases of pooled seroprevalence of both IgG and IgM positivity was 3.0% (95%CI: 1.9–4.4) with a median value of 2.05 and a range values of 0.05–16.62%. Of the Toxoplasma gondii seropositive women, 1281/3389 (34.8%) 174/1765 (32.9%), 1311/3101 (43.7%), and 715/1683 (40.8%) of them had contact with cats, drank unprocessed milk, ate raw or undercooked meat and ate unwashed raw vegetables, respectively. The maternal–fetal outcomes associated with Toxoplasma gondii seropositivity were a history of abortions, miscarriage, stillbirth, intrauterine fetal death, and premature birth, which were found in 868/2990 (32.5%), 112/300 (36.1%), 111/375 (25.7%), 3/157 (1.9%) and 96/362 (20.1%) of women who tested positive for Toxoplasma gondii antibodies. Conclusion: The study found a high proportion of Toxoplasma gondii seroprevalence in pregnant women in the WHO Eastern Mediterranean Region, which may be linked to poor outcomes for mothers and their babies. Thus, pregnant women require monitoring and comprehensive prevention strategies for Toxoplasma gondii infection. [ABSTRACT FROM AUTHOR]

Middle East respiratory syndrome coronavirus (MERS-CoV), first identified in 2012, has emerged as a cause of severe acute respiratory illness in humans. As of May 1, 2016, a total of [...]

Several nations have recently begun to relax their public health protocols, particularly regarding the use of face masks when engaging in outdoor activities. This is because there has been a general trend towards fewer cases of coronavirus disease 2019 (COVID‐19). However, new Omicron sub‐variants (designated BA.4 and BA.5) have recently emerged. These two subvariants are thought to be the cause of an increase in COVID‐19 cases in South Africa, the United States, and Europe. They have also begun to spread throughout Asia. They evolved from the Omicron lineage with characteristics that make them even more contagious and which allow them to circumvent immunity from a previous infection or vaccination. This article reviews a number of scientific considerations about these new variants, including their apparently reduced clinical severity. [ABSTRACT FROM AUTHOR]

A study evaluating the immune response in patients infected with severe acute respiratory syndrome coronavirus (SARS-CoV) showed antivirus antibodies in survivors can be detected by ELISA and immunofluorescence assay (IFA) [...]

Objective: Mildly symptomatic COVID-19 patients may seek medical attention either in the Emergency Department (ED) or Ambulatory Clinics (AC). However, it is unclear if ED patients have different characteristics and outcomes than AC patients when discharged under telemedicine surveillance, which we explored in this study. Methods: Patients with mild or asymptomatic COVID-19 disease referred to a multidisciplinary Telemedicine clinical service (TM-CS) program in an urban tertiary-care hospital, between June 2020 and February 2021, were evaluated. Those referred from ED were labeled “ED Group” and ones from AC as “AC Group.” Their characteristics, clinical features and outcomes including telemedicine parameters, subsequent ED visits, hospital admission, oxygen requirements, intensive care unit (ICU) admission, and mortality were compared. Results: Out of 1132 confirmed non-admitted COVID-19 patients, 526 with mild (89%) or asymptomatic (11%) disease were enrolled in TM-CS. Majority of these were referred from ED (n = 370; 70%) and rest (n = 156, 30%) from the AC. Patients in the ED group compared to AC group, had higher BMI (28.9 vs. 27.5), higher Charlson Comorbidity Index (1.4 vs. 0.9), and higher incidence of comorbidities (50% vs. 22%), P ≤ 0.01. However, there were no differences in the ED and AC groups in subsequent ED visits (26% vs. 24%), hospital admission (18% vs. 15%), oxygen requirements (5% vs. 4%), ICU admission (1% vs. 2%), and mortality (0.3% vs. 0.6%), respectively (P > 0.40). Conclusion: Significant number of mild COVID-19 patients head to the ED for initial assistance but have similar outcomes to AC patients. TM-CS could be a safe alternative for follow-up monitoring of these patients. [ABSTRACT FROM AUTHOR]

The Middle East respiratory syndrome coronavirus (MERS-CoV) causes a highly lethal pneumonia. MERS was recently identified as a candidate for vaccine development, but most efforts focus on antibody responses, which are often transient after CoV infections. CoV-specific T cells are generally long-lived, but the virus-specific T cell response has not been addressed in MERS patients. We obtained peripheral blood mononuclear cells and/or sera from 21 MERS survivors. We detected MERS-CoV-specific CD4+ and CD8+ T cell responses in all MERS survivors and demonstrated functionality by measuring cytokine expression after peptide stimulation. Neutralizing (PRNT50) antibody titers measured in vitro predicted serum protective ability in infected mice and correlated with CD4+ but not CD8+ T cell responses; patients with higher PRNT50 and CD4+ T cell responses had longer intensive care unit stays and prolonged virus shedding and required ventilation. Survivors with undetectable MERS-CoV-specific antibody responses mounted CD8+ T cell responses comparable with those of the whole cohort. There were no correlations between age, disease severity, comorbidities, and virus-specific CD8+ T cell responses. In conclusion, measurements of MERS-CoV-specific T cell responses may be useful for predicting prognosis, monitoring vaccine efficacy, and identifying MERS patients with mild disease in epidemiological studies and will complement virus-specific antibody measurements. [ABSTRACT FROM AUTHOR]

A high percentage of camel handlers in Saudi Arabia are seropositive for Middle East respiratory syndrome coronavirus. We found that 12/100 camel handlers and their family members in Pakistan, a country with extensive camel MERS-CoV infection, were seropositive, indicating that MERS-CoV infection of these populations extends beyond the Arabian Peninsula. [ABSTRACT FROM AUTHOR]

BACKGROUND: Data on the management, clinical course, and outcome of critical patients with Middle East Respiratory Syndrome coronavirus are scarce. We report here our experience and long-term outcome of such patients. METHODS: Subjects intubated for management of ARDS from Middle East Respiratory Syndrome coronavirus pneumonia and ARDS during the April-May 2014 outbreak were included. Their characteristics, ICU course, management, and outcome were evaluated. RESULTS: Fourteen subjects, including 3 health-care workers, met study criteria. Besides 2 health-care workers, all subjects had comorbidities. Predominant symptoms were fever, cough, and dyspnea. The worst median P.../F... ratio of 118 post-intubation was seen on the third day, and median APACHE II score was 27. All subjects received lung-protective ventilation and 1 mg/kg/d methylprednisolone infusion for ARDS. Eleven subjects received ribavirin and peginterferon a-2a. Subjects had a critical ICU course and required neuromuscular blockade (n = 11; 79%), required rescue therapy for respiratory failure (n = 8; 57%), developed shock (n = 10; 71%), and required renal replacement therapy (n = 8; 57%). Declining C-reactive protein levels correlated with clinical improvement despite continued positive real-time polymerase chain reaction results. Nine subjects died in ICU. Five subjects, including 3 health-care workers, were discharged from hospital and were alive after 1 y. CONCLUSIONS: Middle East Respiratory Syndrome coronavirus pneumonia with ARDS has high mortality in subjects with comorbidities. The mainstay of treatment is meticulous ARDS management. Those who survived the acute infection and its complications remained well after 1 y in our study. The role of ribavirin and interferon warrants urgent further evaluation. [ABSTRACT FROM AUTHOR]