Drivers of MERS-CoV transmission: what do we know?

Developments in treatment for middle east respiratory syndrome coronavirus (MERS-CoV)

INTRODUCTION

An important respiratory pathogen that has led to multiple hospital outbreaks both inside and outside of the Arabian Peninsula is the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Given the elevated case fatality rate, there exists a pressing requirement for efficacious therapeutic agents.

AREAS COVERED

This is an updated review of the developments in MERS treatment approaches. Using databases like PubMed, Embase, Cochrane, Scopus, and Google Scholar, a thorough search was carried out utilizing keywords like 'MERS,' 'MERS-CoV,' and 'Middle East respiratory syndrome' in conjunction with 'treatment' or 'therapy' from Jan 2012 to Feb 2024.

EXPERT OPINION

MERS-CoV is a highly pathogenic respiratory infection that emerged in 2012 and continues to pose a significant public health threat. Despite ongoing efforts to control the spread of MERS-CoV, there is currently no specific antiviral treatment available. While many agents have been tested both in vivo and in vitro, none of them have been thoroughly examined in extensive clinical trials. Only case reports, case series, or cohort studies have been made available as clinical studies. However, there is a limited number of randomized-controlled trials. Because cases are irregular and sporadic, conducting a large prospective randomized trials for establishing an efficacious treatment might be difficult.

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is Not Circulating Among Hajj Pilgrims

Since the emergence of the middle east respiratory syndrome coronavirus (MERS-CoV) 2012, the virus had caused multiple healthcare-associated outbreaks. The initial 2012 Hajj season started few weeks after the first case of MERS-CoV, but there were no reported cases among pilgrims in 2012. Since then, there had been multiple studies examining the prevalence of MERS-CoV among Hajj pilgrims. Subsequently, multiple studies utilized screening of pilgrims for MERS-CoV and > 10,000 pilgrims were screened with no identifiable cases of MERS.

Understanding the Role of Environmental Transmission on COVID-19 Herd Immunity and Invasion Potential

COVID-19 is caused by the SARS-CoV-2 virus, which is mainly transmitted directly between humans. However, it is observed that this disease can also be transmitted through an indirect route via environmental fomites. The development of appropriate and effective vaccines has allowed us to target and anticipate herd immunity. Understanding of the transmission dynamics and the persistence of the virus on environmental fomites and their resistive role on indirect transmission of the virus is an important scientific and public health challenge because it is essential to consider all possible transmission routes and route specific transmission strength to accurately quantify the herd immunity threshold. In this paper, we present a mathematical model that considers both direct and indirect transmission modes. Our analysis focuses on establishing the disease invasion threshold, investigating its sensitivity to both transmission routes and isolate route-specific transmission rate. Using the tau-leap algorithm, we perform a stochastic model simulation to address the invasion potential of both transmission routes. Our analysis shows that direct transmission has a higher invasion potential than that of the indirect transmission. As a proof of this concept, we fitted our model with early epidemic data from several countries to uniquely estimate the reproduction numbers associated with direct and indirect transmission upon confirming the identifiability of the parameters. As the indirect transmission possess lower invasion potential than direct transmission, proper estimation and necessary steps toward mitigating it would help reduce vaccination requirement.

A cross-sectional study of epidemiological determinants for Covid-19 infection among nurses of a tertiary care hospital

BACKGROUND

All health care workers including nurses are working in the frontline against coronavirus disease 2019 (Covid-19), which keeps them at high risk of getting infected. This study was conducted to identify risk factors for Covid-19 infection and compliance to Covid appropriate behavior among nurses.

MATERIAL AND METHODS

A cross-sectional study was conducted on 150 nurses in a tertiary care hospital attached to a medical college in Mumbai, from April 2020 to December 2020. Data were collected telephonically using an interviewer-administered pre-validated, semi-structured questionnaire. Data entry and analysis were performed using SPSS version 21.0.

RESULTS

The mean age of the nurses was 38.19 ± 12.14 years. The majority (80.7%) were exposed to Covid-19 while taking active care of Covid patients; a total of 108 (72%) were symptomatic at the time of testing; dietary modifications because of fear of Covid were performed by 121 (80.2%); 92.77% used the appropriate personal protective equipment (PPE) category according to the workplace; 121 (80.77%) followed all steps of donning and doffing at all times, and 19 (12.77%) reported a breach in PPE. A greater proportion of nurses working in Covid duties opted for hospital isolation than home isolation (p = 0.003). Risk factors such as sleep, shift duty, shift pattern, food timing, mode of travel, and type of PPE during travel were also found to be significantly associated with work type - Covid versus non-Covid (p < 0.05).

CONCLUSIONS

Use of workplace appropriate PPE, proper donning and doffing facilities, duty shifts with a fixed duration, adequate hand hygiene practices, and regular food intake with adequate sleep can prevent Covid-19 infection at the workplace among nurses.

Estimation of the Reproductive Number Trend of the Novel Coronavirus "COVID-19" in Southern Iran from July to November 2020

Background

Effective measures to control COVID-19 should be based on an understanding of its epidemiological pattern and the evaluation of its prevalence in the community. This study aimed to examine the reproductive number (R) of COVID-19 and its trend in Fars Province in southern Iran.

Methods

In this ecological study, the R trend was examined from July to November 2020. Data were collected from the daily reports of Shiraz University of Medical Sciences. R is the product of three components, namely the number of infection-producing contacts per unit time, the probability of transmission per contact, and the contagiousness period. Incidence and prevalence rates were used to calculate R. The R value was calculated in Microsoft Excel 2016.

Results

The first and second peaks of COVID-19 were observed on July 6^th and November 22^nd, respectively. The median and mean of R were 1.42 and 1.41, respectively. The highest and lowest values of R were observed on October 20^th (2.60) and September 1^st (0.46), respectively. The values of R had a slightly decreasing trend in the second half of July and November than the first half. In the second half of August and September, an increasing trend was observed than the first half. There was not much change in the second half of October.

Conclusion

The highest value of R was related to the dates when there was a higher probability of exposure to the virus, including public holidays and different occasions on which the probability of people's participation in ceremonies, communities, and gatherings was higher.

Emerging Zoonotic Infections, Social Processes and Their Measurement and Enhanced Surveillance to Improve Zoonotic Epidemic Responses: A "Big Events" Perspective

Zoonotic epidemics and pandemics have become frequent. From HIV/AIDS through COVID-19, they demonstrate that pandemics are social processes as well as health occurrences. The roots of these pandemics lie in changes in the socioeconomic interface between humanity and non-human host species that facilitate interspecies transmission. The degree to which zoonoses spread has been increased by the greater speed and extent of modern transportation and trade. Pre-existing sociopolitical and economic structures and conflicts in societies also affect pathogen propagation. As an epidemic develops, it can itself become a social and political factor, and change and interact with pre-existing sociobehavioral norms and institutional structures. This paper uses a "Big Events" approach to frame these processes. Based on this framework, we discuss how social readiness surveys implemented both before and during an outbreak might help public health predict how overall systems might react to an epidemic and/or to disease control measures, and thus might inform interventions to mitigate potential adverse outcomes or possibly preventing outbreaks from developing into epidemics. We conclude by considering what "pathways measures", in addition to those we and others have already developed, might usefully be developed and validated to assist outbreak and epidemic disease responses.

Middle East Respiratory Syndrome Coronavirus

The past two decades have witnessed the emergence of three zoonotic coronaviruses which have jumped species to cause lethal disease in humans: severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1), Middle East respiratory syndrome coronavirus (MERS-CoV), and SARS-CoV-2. MERS-CoV emerged in Saudi Arabia in 2012 and the origins of MERS-CoV are not fully understood. Genomic analysis indicates it originated in bats and transmitted to camels. Human-to-human transmission occurs in varying frequency, being highest in healthcare environment and to a lesser degree in the community and among family members. Several nosocomial outbreaks of human-to-human transmission have occurred, the largest in Riyadh and Jeddah in 2014 and South Korea in 2015. MERS-CoV remains a high-threat pathogen identified by World Health Organization as a priority pathogen because it causes severe disease that has a high mortality rate, epidemic potential, and no medical countermeasures. MERS-CoV has been identified in dromedaries in several countries in the Middle East, Africa, and South Asia. MERS-CoV-2 causes a wide range of clinical presentations, although the respiratory system is predominantly affected. There are no specific antiviral treatments, although recent trials indicate that combination antivirals may be useful in severely ill patients. Diagnosing MERS-CoV early and implementation infection control measures are critical to preventing hospital-associated outbreaks. Preventing MERS relies on avoiding unpasteurized or uncooked animal products, practicing safe hygiene habits in health care settings and around dromedaries, community education and awareness training for health workers, as well as implementing effective control measures. Effective vaccines for MERS-COV are urgently needed but still under development.

Determining the correlation between comorbidities and MERS-CoV mortality in Saudi Arabia

Objective

As of January 2020, there were 2,519 confirmed Middle East respiratory syndrome coronavirus (MERS-CoV) cases with 866 deaths across 27 countries. Most of these cases (2,121) were reported in Saudi Arabia. Since the initial identification of MERS, few studies have investigated the role of comorbidities that could potentially lead to mortality in cases of the infectious disease. This study aimed to examine the association between comorbidities and MERS mortality in Saudi Arabia.

Methods

This is a retrospective descriptive study. We retrieved the data published by the World Health Organization (WHO) between January 2017 and November 2019, and analysed the association between comorbidities and mortality.

Results

We found 572 MERS-CoV cases reported by WHO in Saudi Arabia during the defined period. Of these, 387 (68%) had a history of chronic illness. The overall mortality rate was found to be 25%. Diabetes mellitus was the most prevalent comorbidity—the mortality rate in the diabetics was 32% as opposed to 12% in the non-diabetics (p-value <0.01). Hypertension was second, with a mortality rate of 35%, as opposed to 15% in the non-hypertensive patients (p-value <0.001). The mortality rate in cases with cardiovascular disease was 39% as opposed to 21% in those without cardiovascular disease (p-value <0.05).

Conclusion

Our study shows that MERS-CoV had a significant case fatality rate in patients with comorbidities. Thus, it will be beneficial if future clinical trials for MERS-CoV examine the impact of improved societal infection control measures such as social distancing and masks, in the context of the coronavirus disease 2019 pandemic, on the prevalence and incidence of MERS and its clinical outcomes.

Product of natural evolution (SARS, MERS, and SARS-CoV-2); deadly diseases, from SARS to SARS-CoV-2

SARS-CoV-2, the virus causing COVID-19, is a single-stranded RNA virus belonging to the order Nidovirales, family Coronaviridae, and subfamily Coronavirinae. SARS-CoV-2 entry to cellsis initiated by the binding of the viral spike protein (S) to its cellular receptor. The roles of S protein in receptor binding and membrane fusion makes it a prominent target for vaccine development. SARS-CoV-2 genome sequence analysis has shown that this virus belongs to the beta-coronavirus genus, which includes Bat SARS-like coronavirus, SARS-CoV and MERS-CoV. A vaccine should induce a balanced immune response to elicit protective immunity. In this review, we compare and contrast these three important CoV diseases and how they inform on vaccine development.

Convalescent plasma therapy for coronavirus infection: experience from MERS and application in COVID-19

The emergence of the COVID-19 pandemic has resulted in a very large number of infections and high number of mortality. There is no specific therapeutic options that are approved for clinical use. Administration of convalescent plasma as a possible therapy was used in the case of viral pneumonia including SARS and influenza. There have been multiple studies of COVID-19 patients utilizing convalescent plasma. These studies employed different dosage levels and different regiments, were observational and lacked control arms, and had variable outcomes. Two of these studies used plasma with anti-SARS-CoV-2 titers of >1:640 to >1:1000. A recent randomized controlled clinical trial showed no benefit of convalescent plasma in patients with severe diseases. However, the study was terminated early and thus further clinical trials are needed to show efficacy in patients with COVID-19 infection.

The Enzymatic Activity of the nsp14 Exoribonuclease Is Critical for Replication of MERS-CoV and SARS-CoV-2

Coronaviruses (CoVs) stand out for their large RNA genome and complex RNA-synthesizing machinery comprising 16 nonstructural proteins (nsps). The bifunctional nsp14 contains 3'-to-5' exoribonuclease (ExoN) and guanine-N7-methyltransferase (N7-MTase) domains. While the latter presumably supports mRNA capping, ExoN is thought to mediate proofreading during genome replication. In line with such a role, ExoN knockout mutants of mouse hepatitis virus (MHV) and severe acute respiratory syndrome coronavirus (SARS-CoV) were previously reported to have crippled but viable hypermutation phenotypes. Remarkably, using reverse genetics, a large set of corresponding ExoN knockout mutations has now been found to be lethal for another betacoronavirus, Middle East respiratory syndrome coronavirus (MERS-CoV). For 13 mutants, viral progeny could not be recovered, unless-as happened occasionally-reversion had first occurred. Only a single mutant was viable, likely because its E191D substitution is highly conservative. Remarkably, a SARS-CoV-2 ExoN knockout mutant was found to be unable to replicate, resembling observations previously made for alpha- and gammacoronaviruses, but starkly contrasting with the documented phenotype of ExoN knockout mutants of the closely related SARS-CoV. Subsequently, we established in vitro assays with purified recombinant MERS-CoV nsp14 to monitor its ExoN and N7-MTase activities. All ExoN knockout mutations that proved lethal in reverse genetics were found to severely decrease ExoN activity while not affecting N7-MTase activity. Our study strongly suggests that CoV nsp14 ExoN has an additional function, which apparently is critical for primary viral RNA synthesis and thus differs from the proofreading function that, based on previous MHV and SARS-CoV studies, was proposed to boost longer-term replication fidelity.IMPORTANCE The bifunctional nsp14 subunit of the coronavirus replicase contains 3'-to-5' exoribonuclease (ExoN) and guanine-N7-methyltransferase domains. For the betacoronaviruses MHV and SARS-CoV, ExoN was reported to promote the fidelity of genome replication, presumably by mediating a form of proofreading. For these viruses, ExoN knockout mutants are viable while displaying an increased mutation frequency. Strikingly, we have now established that the equivalent ExoN knockout mutants of two other betacoronaviruses, MERS-CoV and SARS-CoV-2, are nonviable, suggesting an additional and critical ExoN function in their replication. This is remarkable in light of the very limited genetic distance between SARS-CoV and SARS-CoV-2, which is highlighted, for example, by 95% amino acid sequence identity in their nsp14 sequences. For (recombinant) MERS-CoV nsp14, both its enzymatic activities were evaluated using newly developed in vitro assays that can be used to characterize these key replicative enzymes in more detail and explore their potential as target for antiviral drug development.

Asymptomatic infection by SARS-CoV-2 in healthcare workers: A study in a large teaching hospital in Wuhan, China

OBJECTIVES

To investigate the proportion and characteristics of asymptomatic infection among healthcare workers (HCWs).

METHODS

This study retrospectively investigated 1407 HCWs who were screened for COVID-19 by chest computed tomography (CT) scans and nasopharyngeal swabs for SARS-CoV-2 nucleic acid. Demographics, CT features, nasopharyngeal swabs, baseline symptoms, and laboratory data were collected.

RESULTS

Of 1407 HCWs, 235 had symptoms and 1172 were asymptomatic close contacts, of which, 107 were symptomatic cases and 84 were close contacts who had abnormal CT findings. Of 152 symptomatic individuals and 908 close contacts tested for SARS-CoV-2 nucleic acid, 122 symptomatic cases and 38 close contacts had positive reverse-transcriptase real-time polymerase chain (RT-PCR) test results. The rate of confirmed asymptomatic infections was 4.2% (38/908). Both symptomatic and asymptomatic infected cases had high titrations of specific IgG or had ≥four-fold increase in IgG during convalescence compared with the acute phase. Combining the RT-PCR tests and serological findings, the rate of asymptomatic infections was 9.7% (88/908). In terms of the duration of viral shedding, there was no significant difference between symptomatic mild/moderate participants and asymptomatic infections.

CONCLUSIONS

The findings demonstrated that a high rate of asymptomatic SARS-CoV-2 carriers existed among healthcare worker close contacts during the outbreak of COVID-19.

Winter Is Coming: A Southern Hemisphere Perspective of the Environmental Drivers of SARS-CoV-2 and the Potential Seasonality of COVID-19

SARS-CoV-2 virus infections in humans were first reported in December 2019, the boreal winter. The resulting COVID-19 pandemic was declared by the WHO in March 2020. By July 2020, COVID-19 was present in 213 countries and territories, with over 12 million confirmed cases and over half a million attributed deaths. Knowledge of other viral respiratory diseases suggests that the transmission of SARS-CoV-2 could be modulated by seasonally varying environmental factors such as temperature and humidity. Many studies on the environmental sensitivity of COVID-19 are appearing online, and some have been published in peer-reviewed journals. Initially, these studies raised the hypothesis that climatic conditions would subdue the viral transmission rate in places entering the boreal summer, and that southern hemisphere countries would experience enhanced disease spread. For the latter, the COVID-19 peak would coincide with the peak of the influenza season, increasing misdiagnosis and placing an additional burden on health systems. In this review, we assess the evidence that environmental drivers are a significant factor in the trajectory of the COVID-19 pandemic, globally and regionally. We critically assessed 42 peer-reviewed and 80 preprint publications that met qualifying criteria. Since the disease has been prevalent for only half a year in the northern, and one-quarter of a year in the southern hemisphere, datasets capturing a full seasonal cycle in one locality are not yet available. Analyses based on space-for-time substitutions, i.e., using data from climatically distinct locations as a surrogate for seasonal progression, have been inconclusive. The reported studies present a strong northern bias. Socio-economic conditions peculiar to the 'Global South' have been omitted as confounding variables, thereby weakening evidence of environmental signals. We explore why research to date has failed to show convincing evidence for environmental modulation of COVID-19, and discuss directions for future research. We conclude that the evidence thus far suggests a weak modulation effect, currently overwhelmed by the scale and rate of the spread of COVID-19. Seasonally modulated transmission, if it exists, will be more evident in 2021 and subsequent years.

Observations of the global epidemiology of COVID-19 from the prepandemic period using web-based surveillance: a cross-sectional analysis

Background

Scant data are available about global patterns of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread and global epidemiology of early confirmed cases of COVID-19 outside mainland China. We describe the global spread of SARS-CoV-2 and characteristics of COVID-19 cases and clusters before the characterisation of COVID-19 as a pandemic.

Methods

Cases of COVID-19 reported between Dec 31, 2019, and March 10, 2020 (ie, the prepandemic period), were identified daily from official websites, press releases, press conference transcripts, and social media feeds of national ministries of health or other government agencies. Case characteristics, travel history, and exposures to other cases were abstracted. Countries with at least one case were classified as affected. Early cases were defined as those among the first 100 cases reported from each country. Later cases were defined as those after the first 100 cases. We analysed reported travel to affected countries among the first case reported from each country outside mainland China, demographic and exposure characteristics among cases with age or sex information, and cluster frequencies and sizes by transmission settings.

Findings

Among the first case reported from each of 99 affected countries outside of mainland China, 75 (76%) had recent travel to affected countries; 60 (61%) had travelled to China, Italy, or Iran. Among 1200 cases with age or sex information, 874 (73%) were early cases. Among 762 early cases with age information, the median age was 51 years (IQR 35–63); 25 (3%) of 762 early cases occurred in children younger than 18 years. Overall, 21 (2%) of 1200 cases were in health-care workers and none were in pregnant women. 101 clusters were identified, of which the most commonly identified transmission setting was households (76 [75%]; mean 2·6 cases per cluster [range 2–7]), followed by non-health-care occupational settings (14 [14%]; mean 4·3 cases per cluster [2–14]), and community gatherings (11 [11%]; mean 14·2 cases per cluster [4–36]).

Interpretation

Cases with travel links to China, Italy, or Iran accounted for almost two-thirds of the first reported COVID-19 cases from affected countries. Among cases with age information available, most were among adults aged 18 years and older. Although there were many clusters of household transmission among early cases, clusters in occupational or community settings tended to be larger, supporting a possible role for physical distancing to slow the progression of SARS-CoV-2 spread.

Funding

None.

Middle East Respiratory Syndrome Coronavirus and Severe Acute Respiratory Syndrome Coronavirus

Emerging infectious diseases continue to be of a significant importance worldwide with the potential to cause major outbreaks and global pandemics. In 2002, the world had witnessed the appearance of the severe acute respiratory syndrome coronavirus in China which disappeared abruptly within 6 months. About a decade later, a new and emerging novel coronavirus named the Middle East respiratory syndrome coronavirus (MERS-CoV) was described in a patient from Saudi Arabia. These two coronaviruses shared multiple similarities in the epidemiology, clinical presentations, and posed challenges in its prevention and management. Seven years since its discovery, MERS-CoV continues to be a lethal zoonotic pathogen capable of causing severe pneumonia with high case fatality rates and the ability to cause large health care-associated outbreaks.

The first clusters of Middle East respiratory syndrome coronavirus in Oman: Time to act

INTRODUCTION

Middle East respiratory syndrome coronavirus (MERS-CoV), is an emerging infectious disease of growing global importance. This review describes the latest MERS-CoV clusters and the first cases of nosocomial transmission within health care facilities in Oman. We have highlighted lessons learned and proposed steps to prevent healthcare-associated infections.

METHODS

A descriptive analysis of MERS-CoV cases was conducted between January 23 and February 16, 2019. The data from officials and other published sources used.

RESULTS

Thirteen laboratory-confirmed cases of MERS-CoV were reported from three simultaneous clusters from two governorates without an epidemiological link between the clusters. Two clusters were reported from North Al Batinah Governorate, with nine cases (69%) and 1 cluster from South Ash Sharqiyah Governorate with four cases (31%). In total, four deaths were reported (case fatality rate 31%). Four cases (31%) reported were household contacts from the first cluster, 3 (23%) were nosocomial transmission in health care facilities (two for first and one from the second cluster) and 7 (54%) were community-acquired cases.

CONCLUSIONS

The first local clusters of MERS-CoV reported with evidence suggestive of healthcare and household-associated transmission. Early diagnosis and strict implementation of infection control measures remain fundamental in preventing and managing MERS-CoV infection.

COVID-19 R0: Magic number or conundrum?

There is an increasing concern about COVID-19 worldwide. [...]

Middle East respiratory syndrome coronavirus in the last two years: Health care workers still at risk

BACKGROUND

An important emerging respiratory virus is the Middle East respiratory syndrome coronavirus (MERS-CoV). MERS-CoV had been associated with a high case fatality rate especially among severe cases.

METHODS

This is a retrospective analysis of reported MERS-CoV cases between December 2016 and January 2019, as retrieved from the World Health Organization. The aim of this study is to examine the epidemiology of reported cases and quantify the percentage of health care workers (HCWs) among reported cases.

RESULTS

There were 403 reported cases with a majority being men (n = 300; 74.4%). These cases were reported from Lebanon, Malaysia, Oman, Qatar, Saudi Arabia, and United Arab Emirates. HCWs represented 26% and comorbidities were reported among 71% of non-HCWs and 1.9% among HCWs (P < .0001). Camel exposure and camel milk ingestion were reported in 64% each, and the majority (97.8%) of those with camel exposures had camel milk ingestion. There were 58% primary cases and 42% were secondary cases. The case fatality rate was 16% among HCWs compared with 34% among other patients (P = .001). The mean age ± SD was 47.65 ± 16.28 for HCWs versus 54.23 ± 17.34 for non-HCWs (P = .001).

CONCLUSIONS

MERS-CoV infection continues to have a high case fatality rate and a large proportion of patients were HCWs. Further understanding of the disease transmission and prevention mainly in health care settings are needed.

A Systematic Review of therapeutic agents for the treatment of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

BACKGROUND

The Middle East Respiratory Syndrome Coronavirus (MERS-CoV) was first described in 2012 and attracted a great international attention due to multiple healthcare associated outbreaks. The disease carries a high case fatality rate of 34.5%, and there is no internationally or nationally recommended therapy.

METHOD

We searched MEDLINE, Science Direct, Embase and Scopus databases for relevant papers published till March 2019 describing in vitro, in vivo or human therapy of MERS.

RESULTS

Initial search identified 62 articles: 52 articles were from Medline, 6 from Embase, and 4 from Science Direct. Based on the inclusions and exclusions criteria, 30 articles were included in the final review and comprised: 22 in vitro studies, 8 studies utilizing animal models, 13 studies in humans, and one study included both in vitro and animal model. There are a few promising therapeutic agents on the horizon. The combination of lopinavir/ritonavir and interferon-beta- 1b showed excellent results in common marmosets and currently is in a randomized control trial. Ribavirin and interferon were the most widely used combination and experience comes from a number of observational studies. Although, the data are heterogenous, this combination might be of potential benefit and deserve further investigation. There were no randomized clinical trials to recommend specific therapy for the treatment of MERS-CoV infection. Only one such study is planned for randomization and is pending completion. The study is based on a combination of lopinavir/ritonavir and interferon-beta- 1b. A fully human polyclonal IgG antibody (SAB-301) was safe and well tolerated in healthy individuals and this agent may deserve further testing for efficacy.

CONCLUSION

Despite multiple studies in humans there is no consensus on the optimal therapy for MERS-CoV. Randomized clinical trials are needed and potential therapies should be evaluated only in such clinical trials. In order to further enhance the therapeutic aroma for MERS-CoV infection, repurposing old drugs against MERS-CoV is an interesting strategy and deserves further consideration and use in clinical settings.

Clinical predictors of mortality of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection: A cohort study

Background

Since the emergence of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in 2012, the virus had caused a high case fatality rate. The clinical presentation of MERS varied from asymptomatic to severe bilateral pneumonia, depending on the case definition and surveillance strategies. There are few studies examining the mortality predictors in this disease. In this study, we examined clinical predictors of mortality of Middle East Respiratory Syndrome (MERS) infection.

Methods

This is a retrospective analysis of symptomatic admitted patients to a large tertiary MERS-CoV center in Saudi Arabia over the period from April 2014 to March 2018. Clinical and laboratory data were collected and analysis was done using a binary regression model.

Results

A total of 314 symptomatic MERS-CoV patients were included in the analysis, with a mean age of 48 (±17.3) years. Of these cases, 78 (24.8%) died. The following parameters were associated with increased mortality, age, WBC, neutrophil count, serum albumin level, use of a continuous renal replacement therapy (CRRT) and corticosteroid use. The odd ratio for mortality was highest for CRRT and corticosteroid use (4.95 and 3.85, respectively). The use of interferon-ribavirin was not associated with mortality in this cohort.

Conclusion

Several factors contributed to increased mortality in this cohort of MERS-CoV patients. Of these factors, the use of corticosteroid and CRRT were the most significant. Further studies are needed to evaluate whether these factors were a mark of severe disease or actual contributors to higher mortality.

MERS-CoV as an emerging respiratory illness: A review of prevention methods

INTRODUCTION

Middle East Respiratory Coronavirus Virus (MERS-CoV) first emerged from Saudi Arabia in 2012 and has since been recognized as a significant human respiratory pathogen on a global level.

METHODS

In this narrative review, we focus on the prevention of MERS-CoV. We searched PubMed, Embase, Cochrane, Scopus, and Google Scholar, using the following terms: 'MERS', 'MERS-CoV', 'Middle East respiratory syndrome' in combination with 'prevention' or 'infection control'. We also reviewed the references of each article to further include other studies or reports not identified by the search.

RESULTS

As of Nov 2019, a total of 2468 laboratory-confirmed cases of MERS-CoV were diagnosed mostly from Middle Eastern regions with a mortality rate of at least 35%. A major outbreak that occurred outside the Middle East (in South Korea) and infections reported from 27 countries. MERS-CoV has gained recognition as a pathogen of global significance. Prevention of MERS-CoV infection is a global public health priority. Healthcare facility transmission and by extension community transmission, the main amplifier of persistent outbreaks, can be prevented through early identification and isolation of infected humans. While MERS-CoV vaccine studies were initially hindered by multiple challenges, recent vaccine development for MERS-CoV is showing promise.

CONCLUSIONS

The main factors leading to sustainability of MERS-CoV infection in high risk courtiers is healthcare facility transmission. MERS-CoV transmission in healthcare facility mainly results from laps in infection control measures and late isolation of suspected cases. Preventive measures for MERS-CoV include disease control in camels, prevention of camel to human transmission.

Asymptomatic Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection: Extent and implications for infection control: A systematic review

Background

The Middle East Respiratory Syndrome Coronavirus (MERS-CoV) emerged in 2012 and attracted an international attention as the virus caused multiple healthcare associated outbreaks. There are reports of the role of asymptomatic individuals in the transmission of MERS-CoV, however, the exact role is not known.

Method

The MEDLINE/PubMed and Scopus databases were searched for relevant papers published till August 2018 describing asymptomatic MERS-CoV infection.

Results

A total of 10 papers were retrieved and included in the final analysis and review. The extent of asymptomatic MERS infection had increased with change in the policy of testing asymptomatic contacts. In early cases in April 2012–October 2013, 12.5% were asymptomatic among 144 PCR laboratory-confirmed MERS-CoV cases while in 2014 the proportion rose to 25.1% among 255 confirmed cases. The proportion of asymptomatic cases reported among pediatric confirmed MERS-CoV cases were higher (41.9%–81.8%). Overall, the detection rate of MERS infection among asymptomatic contacts was 1-3.9% in studies included in this review. Asymptomatic individuals were less likely to have underlying condition compared to fatal cases. Of particular interest is that most of the identified pediatric cases were asymptomatic with no clear explanation.

Conclusions

The proportion of asymptomatic MERS cases were detected with increasing frequency as the disease progressed overtime. Those patients were less likely to have comorbid disease and may contribute to the transmission of the virus.

Healthcare-associated infections: the hallmark of Middle East respiratory syndrome coronavirus with review of the literature

Middle East respiratory syndrome coronavirus (MERS-CoV) is capable of causing acute respiratory illness. Laboratory-confirmed MERS-CoV cases may be asymptomatic, have mild disease, or have a life-threatening infection with a high case fatality rate. There are three patterns of transmission: sporadic community cases from presumed non-human exposure, family clusters arising from contact with an infected family index case, and healthcare-acquired infections among patients and from patients to healthcare workers. Healthcare-acquired MERS infection has become a well-known characteristic of the disease and a leading means of spread. The main factors contributing to healthcare-associated outbreaks include delayed recognition, inadequate infection control measures, inadequate triaging and isolation of suspected MERS or other respiratory illness patients, crowding, and patients remaining in the emergency department for many days. A review of the literature suggests that effective control of hospital outbreaks was accomplished in most instances by the application of proper infection control procedures. Prompt recognition, isolation and management of suspected cases are key factors for prevention of the spread of MERS. Repeated assessments of infection control and monitoring of corrective measures contribute to changing the course of an outbreak. Limiting the number of contacts and hospital visits are also important factors to decrease the spread of infection.

Middle East respiratory syndrome coronavirus transmission among health care workers: Implication for infection control

Background

Many outbreaks of Middle East respiratory syndrome coronavirus (MERS-CoV) have occurred in health care settings and involved health care workers (HCWs). We describe the occurrence of an outbreak among HCWs and attempt to characterize at-risk exposures to improve future infection control interventions.

Methods

This study included an index case and all HCW contacts. All contacts were screened for MERS-CoV using polymerase chain reaction.

Results

During the study period in 2015, the index case was a 30-year-old Filipino nurse who had a history of unprotected exposure to a MERS-CoV–positive case on May 15, 2015, and had multiple negative tests for MERS-CoV. Weeks later, she was diagnosed with pulmonary tuberculosis and MERS-CoV infection. A total of 73 staff were quarantined for 14 days, and nasopharyngeal swabs were taken on days 2, 5, and 12 postexposure. Of those contacts, 3 (4%) were confirmed positive for MERS-CoV. An additional 18 staff were quarantined and had MERS-CoV swabs. A fourth case was confirmed positive on day 12. Subsequent contact investigations revealed a fourth-generation transmission. Only 7 (4.5%) of the total 153 contacts were positive for MERS-CoV.

Conclusions

The role of HCWs in MERS-CoV transmission is complex. Although most MERS-CoV–infected HCWs are asymptomatic or have mild disease, fatal infections can occur and HCWs can play a major role in propagating health care facility outbreaks. This investigation highlights the need to continuously review infection control guidance relating to the role of HCWs in MERS-CoV transmission in health care outbreaks, especially as it relates to the complex questions on definition of risky exposures, who to test, and the frequency of MERS-CoV testing; criteria for who to quarantine and for how long; and clearance and return to active duty criteria.

Influenza is more common than Middle East Respiratory Syndrome Coronavirus (MERS-CoV) among hospitalized adult Saudi patients

BACKGROUND

Since the initial description of Middle East Respiratory Syndrome Coronavirus (MERS-CoV), we adopted a systematic process of screening patients admitted with community acquired pneumonia. Here, we report the result of the surveillance activity in a general hospital in Saudi Arabia over a four year period.

MATERIALS AND METHODS

All admitted patients with community acquired pneumonia from 2012 to 2016 were tested for MERS-CoV. In addition, testing for influenza viruses was carried out starting April 2015.

RESULTS

During the study period, a total of 2657 patients were screened for MERS-CoV and only 20 (0.74%) tested positive. From January 2015 to December 2016, a total of 1644 patients were tested for both MERS-CoV and influenza. None of the patients tested positive for MERS-CoV and 271 (16.4%) were positive for influenza. The detected influenza viruses were Influenza A (107, 6.5%), pandemic 2009 H1N1 (n = 120, 7.3%), and Influenza B (n = 44, 2.7%). Pandemic H1N1 was the most common influenza in 2015 with a peak in peaked October to December and influenza A other than H1N1 was more common in 2016 with a peak in August and then October to December.

CONCLUSIONS

MERS-CoV was a rare cause of community acquired pneumonia and other viral causes including influenza were much more common. Thus, admitted patients are potentially manageable with Oseltamivir or Zanamivir therapy.

Dynamics of scientific publications on the MERS-CoV outbreaks in Saudi Arabia

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is an emerging disease with a relatively high case fatality rate. Most cases have been reported from Saudi Arabia, and the disease epidemic potential is considered to be limited. However, human-human transmission has occurred, usually in the context of healthcare facility-associated outbreaks. The scientific and medical community depends on timely publication of epidemiological information on emerging diseases during outbreaks to appropriately target public health responses. In this review, we considered the academic response to four MERS CoV outbreaks that occurred in Al-Hasa in 2013, Jeddah in 2014 and Riyadh in 2014 and 2015. We analysed 68 relevant epidemiology articles. For articles for which submission dates were available, six articles were submitted during the course of an outbreak. One article was published within a month of the Al-Hasa outbreak, and one each was accepted during the Jeddah and Riyadh outbreaks. MERS-CoV epidemiology articles were cited more frequently than articles on other subjects in the same journal issues. Thus, most epidemiology articles on MERS-CoV were published with no preferential advantage over other articles. Collaboration of the research community and the scientific publishing industry is needed to facilitate timely publication of emerging infectious diseases.

Middle East respiratory syndrome coronavirus disease is rare in children: An update from Saudi Arabia

AIM

To summarize the reported Middle East respiratory syndrome-coronavirus (MERS-CoV) cases, the associated clinical presentations and the outcomes.

METHODS

We searched the Saudi Ministry of Health website, the World Health Organization website, and the Flutracker website. We also searched MEDLINE and PubMed for the keywords: Middle East respiratory syndrome-coronavirus, MERS-CoV in combination with pediatric, children, childhood, infancy and pregnancy from the initial discovery of the virus in 2012 to 2016. The retrieved articles were also read to further find other articles. Relevant data were placed into an excel sheet and analyzed accordingly. Descriptive analytic statistics were used in the final analysis as deemed necessary.

RESULTS

From June 2012 to April 19, 2016, there were a total of 31 pediatric MERS-CoV cases. Of these cases 13 (42%) were asymptomatic and the male to female ratio was 1.7:1. The mean age of patients was 9.8 ± 5.4 years. Twenty-five (80.6%) of the cases were reported from the Kingdom of Saudi Arabia. The most common source of infection was household contact (10 of 15 with reported source) and 5 patients acquired infection within a health care facility. Using real time reverse transcriptase polymerase chain reaction of pediatric patients revealed that 9 out of 552 (1.6%) was positive in the Kingdom of Saudi Arabia.

CONCLUSION

Utilizing serology for MERS-CoV infection in Jordan and Saudi Arabia did not reveal any positive patients. Thus, the number of the pediatric MERS-CoV is low; the exact reason for the low prevalence of the disease in children is not known.