Middle East respiratory syndrome coronavirus infection profile in Qatar: An 8-year experience

Middle East Respiratory Syndrome Coronavirus Could be a Priority Pathogen to Cause Public Health Emergency: Noticeable Features and Counteractive Measures

Middle East respiratory syndrome (MERS) is caused by a specific strain of the 6 types of human coronaviruses (HCoV). MERS-CoV has spread unchecked since it was first discovered in Saudi Arabia in 2012. The virus most likely spreads through nosocomial and zoonotic channels. Genetic analyses suggest that bats were the initial hosts and that the disease spread to camels. Person-to-person transmission occurs with varying frequency, being most prevalent in clinical settings and the least common among the general population and among close relatives. Due to the severity of the illness, high fatality rate, potential for epidemic spread, and lack of adequate medical countermeasures, the World Health Organization (WHO) continues to list MERS-CoV as a priority pathogen. While no specific antiviral medicines exist, a combination of antivirals has shown promise in recent clinical trials. Vaccines against MERS-CoV are critically needed and are currently being developed. Early diagnosis and implementing appropriate infection control measures are keys to preventing hospital-associated outbreaks. Preventive measures include avoiding raw or undercooked meats and other animal products, ensuring proper hand hygiene in healthcare settings and around dromedaries, educating the public and healthcare personnel about the disease, and adhering to other recommended practices. Countries with a high prevalence of MERS should adhere to regulations designed to limit the transmission of the virus. The recent spread of MERS-CoV highlights the importance of public awareness regarding the significance of reporting symptoms so that appropriate control measures can be adopted. The narrative review discusses the incidence of MERS, its clinical presentation, potential transmission routes, recent reports, preventative and control measures, and current therapeutic options.

Middle East respiratory syndrome coronavirus and the 2022 world cup football tournament in Qatar

No Middle East respiratory syndrome coronavirus cases were detected during the 2022 FIFA World Cup in Qatar in November–December 2022, which attracted 1.4 million visitors. Robust monitoring mechanisms instituted by Qatar before and during the FIFA WC can serve as a template for future similar events to detect infectious diseases of global importance.

Assessment of Broadly Reactive Responses in Patients With MERS-CoV Infection and SARS-CoV-2 Vaccination

Importance

In the ongoing COVID-19 pandemic, there remain unanswered questions regarding the nature and importance of the humoral immune response against other coronaviruses. Although coinfection of the Middle East respiratory syndrome coronavirus (MERS-CoV) with the SARS-CoV-2 has not been documented yet, several patients previously infected with MERS-CoV received the COVID-19 vaccine; data describing how preexisting MERS-CoV immunity may shape the response to SARS-CoV-2 following infection or vaccination are lacking.

Objective

To characterize the cross-reactive and protective humoral responses in patients exposed to both MERS-CoV infection and SARS-CoV-2 vaccination.

Design, Setting, and Participants

This cohort study involved a total of 18 sera samples collected from 14 patients with MERS-CoV infection before (n = 12) and after (n = 6) vaccination with 2 doses of COVID-19 mRNA vaccine (BNT162b2 or mRNA-1273). Of those patients, 4 had prevaccination and postvaccination samples. Antibody responses to SARS-CoV-2 and MERS-CoV were assessed as well as cross-reactive responses to other human coronaviruses.

Main Outcomes and Measures

The main outcomes measured were binding antibody responses, neutralizing antibodies, and antibody-dependent cellular cytotoxicity (ADCC) activity. Binding antibodies targeting SARS-CoV-2 main antigens (spike [S], nucleocapsid, and receptor-binding domain) were detected using automated immunoassays. Cross-reactive antibodies with the S1 protein of SARS-CoV, MERS-CoV, and common human coronaviruses were analyzed using a bead-based assay. Neutralizing antibodies (NAbs) against MERS-CoV and SARS-CoV-2 as well as ADCC activity against SARS-CoV-2 were assessed.

Results

A total of 18 samples were collected from 14 male patients with MERS-CoV infection (mean [SD] age, 43.8 [14.6] years). Median (IQR) duration between primary COVID-19 vaccination and sample collection was 146 (47-189) days. Prevaccination samples had high levels of anti-MERS S1 immunoglobin M (IgM) and IgG (reactivity index ranging from 0.80 to 54.7 for IgM and from 0.85 to 176.3 for IgG). Cross-reactive antibodies with SARS-CoV and SARS-CoV-2 were also detected in these samples. However, cross-reactivity against other coronaviruses was not detected by the microarray assay. Postvaccination samples showed significantly higher levels of total antibodies, IgG, and IgA targeting SARS-CoV-2 S protein compared with prevaccination samples (eg, mean total antibodies: 8955.0 AU/mL; 95% CI, -5025.0 to 22936.0 arbitrary units/mL; P = .002). In addition, significantly higher anti-SARS S1 IgG levels were detected following vaccination (mean reactivity index, 55.4; 95% CI, -9.1 to 120.0; P = .001), suggesting potential cross-reactivity with these coronaviruses. Also, anti-S NAbs were significantly boosted against SARS-CoV-2 (50.5% neutralization; 95% CI, 17.6% to 83.2% neutralization; P < .001) after vaccination. Furthermore, there was no significant increase in antibody-dependent cellular cytotoxicity against SARS-CoV-2 S protein postvaccination.

Conclusions and Relevance

This cohort study found a significant boost in cross-reactive NAbs in some patients exposed to MERS-CoV and SARS-CoV-2 antigens. These findings suggest that isolation of broadly reactive antibodies from these patients may help guide the development of a pancoronavirus vaccine by targeting cross-reactive epitopes between distinct strains of human coronaviruses.

Genetic diversity of hepatitis E virus (HEV) in imported and domestic camels in Saudi Arabia

Camels gained attention since the discovery of MERS-CoV as intermediary hosts for potentially epidemic zoonotic viruses. DcHEV is a novel zoonotic pathogen associated with camel contact. This study aimed to genetically characterize DcHEV in domestic and imported camels in Saudi Arabia. DcHEV was detected by RT-PCR in serum samples, PCR-positive samples were subjected to sequencing and phylogenetic analyses. DcHEV was detected in 1.77% of samples with higher positivity in domestic DCs. All positive imported dromedaries were from Sudan with age declining prevalence. Domestic DcHEV sequences clustered with sequences from Kenya, Somalia, and UAE while imported sequences clustered with one DcHEV isolate from UAE and both sequences clustered away from isolates reported from Pakistan. Full-genome sequences showed 24 amino acid difference with reference sequences. Our results confirm the detection of DcHEV in domestic and imported DCs. Further investigations are needed in human and camel populations to identify DcHEV potential zoonosis threat.

Comparative evaluation of ventilator-associated pneumonia in critically ill COVID- 19 and patients infected with other corona viruses: a systematic review and meta-analysis

The Coronavirus disease 19 (COVID-19) pandemic is associated with an unprecedented requirement for intensive care unit (ICU) admission, invasive mechanical ventilation, and thereby significantly increasing the risk of secondary nosocomial pneumonia, Ventilator-Associated Pneumonia (VAP). Our study aims to identify the overall incidence of VAP, common organisms associated with it, and outcome in COVID-19 patients in comparison to the non-SARS-CoV-2 infected critically ill ventilated COVID-19 patients. A comprehensive screening was conducted using major electronic databases), from January 1st 2020 to May 31st 2021, as per the PRISMA statement. In our rapid review, we included a total of 34 studies (involving 8901 cases. Overall VAP was reported in 48.15 % (95% CI 42.3%-54%) mechanically ventilated COVID-19 patients and the mortality rate was 51.4% (95% CI 42.5%-60%). COVID-19 patients had increased risk of VAP and mortality in comparison to other non-SARS-CoV-2 viral pneumonia (OR=2.33; 95%CI 1.75-3.11; I2=15%, and OR=1.46; 95%CI 1.15-1.86; I2=0% respectively). Critically ill COVID-19 patients are prone to develop VAP, which worsens the outcome.