Middle East Respiratory Syndrome coronavirus (MERS-CoV) serology in major livestock species in an affected region in Jordan, June to September 2013

Acute middle East respiratory syndrome coronavirus infection in livestock Dromedaries, Dubai, 2014

Camels carry Middle East respiratory syndrome coronavirus, but little is known about infection age or prevalence. We studied >800 dromedaries of all ages and 15 mother–calf pairs. This syndrome constitutes an acute, epidemic, and time-limited infection in camels <4 years of age, particularly calves. Delayed social separation of calves might reduce human infection risk.

MERS coronavirus: diagnostics, epidemiology and transmission

The first known cases of Middle East respiratory syndrome (MERS), associated with infection by a novel coronavirus (CoV), occurred in 2012 in Jordan but were reported retrospectively. The case first to be publicly reported was from Jeddah, in the Kingdom of Saudi Arabia (KSA). Since then, MERS-CoV sequences have been found in a bat and in many dromedary camels (DC). MERS-CoV is enzootic in DC across the Arabian Peninsula and in parts of Africa, causing mild upper respiratory tract illness in its camel reservoir and sporadic, but relatively rare human infections. Precisely how virus transmits to humans remains unknown but close and lengthy exposure appears to be a requirement. The KSA is the focal point of MERS, with the majority of human cases. In humans, MERS is mostly known as a lower respiratory tract (LRT) disease involving fever, cough, breathing difficulties and pneumonia that may progress to acute respiratory distress syndrome, multiorgan failure and death in 20% to 40% of those infected. However, MERS-CoV has also been detected in mild and influenza-like illnesses and in those with no signs or symptoms. Older males most obviously suffer severe disease and MERS patients often have comorbidities. Compared to severe acute respiratory syndrome (SARS), another sometimes- fatal zoonotic coronavirus disease that has since disappeared, MERS progresses more rapidly to respiratory failure and acute kidney injury (it also has an affinity for growth in kidney cells under laboratory conditions), is more frequently reported in patients with underlying disease and is more often fatal. Most human cases of MERS have been linked to lapses in infection prevention and control (IPC) in healthcare settings, with approximately 20% of all virus detections reported among healthcare workers (HCWs) and higher exposures in those with occupations that bring them into close contact with camels. Sero-surveys have found widespread evidence of past infection in adult camels and limited past exposure among humans. Sensitive, validated reverse transcriptase real-time polymerase chain reaction (RT-rtPCR)-based diagnostics have been available almost from the start of the emergence of MERS. While the basic virology of MERS-CoV has advanced over the past three years, understanding of the interplay between camel, environment, and human remains limited.

Bat origin of human coronaviruses

Bats have been recognized as the natural reservoirs of a large variety of viruses. Special attention has been paid to bat coronaviruses as the two emerging coronaviruses which have caused unexpected human disease outbreaks in the 21st century, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV), are suggested to be originated from bats. Various species of horseshoe bats in China have been found to harbor genetically diverse SARS-like coronaviruses. Some strains are highly similar to SARS-CoV even in the spike protein and are able to use the same receptor as SARS-CoV for cell entry. On the other hand, diverse coronaviruses phylogenetically related to MERS-CoV have been discovered worldwide in a wide range of bat species, some of which can be classified to the same coronavirus species as MERS-CoV. Coronaviruses genetically related to human coronavirus 229E and NL63 have been detected in bats as well. Moreover, intermediate hosts are believed to play an important role in the transmission and emergence of these coronaviruses from bats to humans. Understanding the bat origin of human coronaviruses is helpful for the prediction and prevention of another pandemic emergence in the future.

A phylogenetically distinct Middle East respiratory syndrome coronavirus detected in a dromedary calf from a closed dairy herd in Dubai with rising seroprevalence with age

Middle East respiratory syndrome coronavirus (MERS-CoV) was detected by monoclonal antibody-based nucleocapsid protein-capture enzyme-linked immunosorbent assay (ELISA), RNA detection, and viral culture from the nasal sample of a 1-month-old dromedary calf in Dubai with sudden death. Whole genome phylogeny showed that this MERS-CoV strain did not cluster with the other MERS-CoV strains from Dubai that we reported recently. Instead, it formed a unique branch more closely related to other MERS-CoV strains from patients in Qatar and Hafr-Al-Batin in Saudi Arabia, as well as the MERS-CoV strains from patients in the recent Korean outbreak, in which the index patient acquired the infection during travel in the eastern part of the Arabian Peninsula. Non-synonymous mutations, resulting in 11 unique amino acid differences, were observed between the MERS-CoV genome from the present study and all the other available MERS-CoV genomes. Among these 11 unique amino acid differences, four were found in ORF1ab, three were found in the S1 domain of the spike protein, and one each was found in the proteins encoded by ORF4b, ORF5, envelope gene, and ORF8. MERS-CoV detection for all other 254 dromedaries in this closed dairy herd was negative by nucleocapsid protein-capture ELISA and RNA detection. MERS-CoV IgG sero-positivity gradually increased in dromedary calves with increasing age, with positivity rates of 75% at zero to three months, 79% at four months, 89% at five to six months, and 90% at seven to twelve months. The development of a rapid antigen detection kit for instantaneous diagnosis is warranted.Emerging Microbes & Infections (2015) 4, e74; doi:10.1038/emi.2015.74; published online 2 December 2015.

Evidence for zoonotic origins of Middle East respiratory syndrome coronavirus

Middle East respiratory syndrome (MERS) is an emerging infectious disease, caused by Middle East respiratory syndrome coronavirus (MERS-CoV) and is considered to be a zoonosis. However, the natural reservoirs of MERS-CoV remain obscure, with bats and camels as the most suspected sources. In this article, we review the evidence supporting a bat/camel origin of human MERS-CoV infection and current knowledge on the modes of camel-to-human transmission of MERS-CoV.

Serological Evidence of MERS-CoV Antibodies in Dromedary Camels (Camelus dromedaries) in Laikipia County, Kenya

Middle East respiratory syndrome coronavirus (MERS-CoV) is a recently identified virus causing severe viral respiratory illness in people. Little is known about the reservoir in the Horn of Africa. In Kenya, where no human MERS cases have been reported, our survey of 335 dromedary camels, representing nine herds in Laikipia County, showed a high seroprevalence (46.9%) to MERS-CoV antibodies. Between herd differences were present (14.3%– 82.9%), but was not related to management type or herd isolation. Further research should focus on identifying similarity between MERS-CoV viral isolates in Kenya and clinical isolates from the Middle East and elsewhere.

Middle East respiratory syndrome coronavirus (MERS-CoV): what lessons can we learn?

The Middle East Respiratory Coronavirus (MERS-CoV) was first isolated from a patient who died with severe pneumonia in June 2012. As of 19 June 2015, a total of 1,338 MERS-CoV infections have been notified to the World Health Organization (WHO). Clinical illness associated with MERS-CoV ranges from mild upper respiratory symptoms to rapidly progressive pneumonia and multi-organ failure. A significant proportion of patients present with non-respiratory symptoms such as headache, myalgia, vomiting and diarrhoea. A few potential therapeutic agents have been identified but none have been conclusively shown to be clinically effective. Human to human transmission is well documented, but the epidemic potential of MERS-CoV remains limited at present. Healthcare-associated clusters of MERS-CoV have been responsible for the majority of reported cases. The largest outbreaks have been driven by delayed diagnosis, overcrowding and poor infection control practices. However, chains of MERS-CoV transmission can be readily interrupted with implementation of appropriate control measures. As with any emerging infectious disease, guidelines for MERS-CoV case identification and surveillance evolved as new data became available. Sound clinical judgment is required to identify unusual presentations and trigger appropriate control precautions. Evidence from multiple sources implicates dromedary camels as natural hosts of MERS-CoV. Camel to human transmission has been demonstrated, but the exact mechanism of infection remains uncertain. The ubiquitously available social media have facilitated communication and networking amongst healthcare professionals and eventually proved to be important channels for presenting the public with factual material, timely updates and relevant advice.

Junctional and allele-specific residues are critical for MERS-CoV neutralization by an exceptionally potent germline-like antibody

The MERS-CoV is an emerging virus, which already infected more than 1,300 humans with high (∼36%) mortality. Here, we show that m336, an exceptionally potent human anti-MERS-CoV antibody, is almost germline with only one somatic mutation in the heavy chain. The structure of Fab m336 in complex with the MERS-CoV receptor-binding domain reveals that its IGHV1-69-derived heavy chain provides more than 85% binding surface and that its epitope almost completely overlaps with the receptor-binding site. Analysis of antibodies from 69 healthy humans suggests an important role of the V(D)J recombination-generated junctional and allele-specific residues for achieving high affinity of binding at such low levels of somatic hypermutation. Our results also have important implications for development of vaccine immunogens based on the newly identified m336 epitope as well as for elucidation of mechanisms of neutralization by m336-like antibodies and their elicitation in vivo.

m336 is an exceptionally potent germline-like antibody against the emerging MERS-CoV virus. Here, the authors solve the structure of m336 in complex with MERS-CoV receptor-binding domain and use it to reveal a role of junctional and allele-specific residues in the interaction and suggest implications for vaccine development.

Middle East respiratory syndrome

Middle East respiratory syndrome (MERS) is a highly lethal respiratory disease caused by a novel single-stranded, positive-sense RNA betacoronavirus (MERS-CoV). Dromedary camels, hosts for MERS-CoV, are implicated in direct or indirect transmission to human beings, although the exact mode of transmission is unknown. The virus was first isolated from a patient who died from a severe respiratory illness in June, 2012, in Jeddah, Saudi Arabia. As of May 31, 2015, 1180 laboratory-confirmed cases (483 deaths; 40% mortality) have been reported to WHO. Both community-acquired and hospital-acquired cases have been reported with little human-to-human transmission reported in the community. Although most cases of MERS have occurred in Saudi Arabia and the United Arab Emirates, cases have been reported in Europe, the USA, and Asia in people who travelled from the Middle East or their contacts. Clinical features of MERS range from asymptomatic or mild disease to acute respiratory distress syndrome and multiorgan failure resulting in death, especially in individuals with underlying comorbidities. No specific drug treatment exists for MERS and infection prevention and control measures are crucial to prevent spread in health-care facilities. MERS-CoV continues to be an endemic, low-level public health threat. However, the virus could mutate to have increased interhuman transmissibility, increasing its pandemic potential.

Middle East respiratory syndrome coronavirus (MERS-CoV): what lessons can we learn?

The Middle East Respiratory Coronavirus (MERS-CoV) was first isolated from a patient who died with severe pneumonia in June 2012. As of 19 June 2015, a total of 1,338 MERS-CoV infections have been notified to the World Health Organization (WHO). Clinical illness associated with MERS-CoV ranges from mild upper respiratory symptoms to rapidly progressive pneumonia and multi-organ failure. A significant proportion of patients present with non-respiratory symptoms such as headache, myalgia, vomiting and diarrhoea. A few potential therapeutic agents have been identified but none have been conclusively shown to be clinically effective. Human to human transmission is well documented, but the epidemic potential of MERS-CoV remains limited at present. Healthcare-associated clusters of MERS-CoV have been responsible for the majority of reported cases. The largest outbreaks have been driven by delayed diagnosis, overcrowding and poor infection control practices. However, chains of MERS-CoV transmission can be readily interrupted with implementation of appropriate control measures. As with any emerging infectious disease, guidelines for MERS-CoV case identification and surveillance evolved as new data became available. Sound clinical judgment is required to identify unusual presentations and trigger appropriate control precautions. Evidence from multiple sources implicates dromedary camels as natural hosts of MERS-CoV. Camel to human transmission has been demonstrated, but the exact mechanism of infection remains uncertain. The ubiquitously available social media have facilitated communication and networking amongst healthcare professionals and eventually proved to be important channels for presenting the public with factual material, timely updates and relevant advice.

Enteric viral infections in lambs or kids

Diarrhoea in lambs and kids is often a complex, multi-factorial syndrome. Common infectious causes of diarrhoea in lambs and kids during the first month of life are of bacterial or parasite nature. However, despite appreciable improvements in management practices and prevention and treatment strategies over the last decades, diarrhoea is still a common and costly syndrome affecting newborn small ruminants. Recent advances in the diagnostics and metagenomic investigations of the enteric environment have allowed discovering a number of novel viruses, although their pathobiological properties remain largely unknown. Assessing more in depth the impact of these viruses on the health and productions of these livestock animals is necessary and requires the development of accurate diagnostic tools and updating of the diagnostic algorithms of enteric pathological conditions.

Dromedary Camels and the Transmission of Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

Middle East respiratory syndrome coronavirus (MERS‐CoV) is an existential threat to global public health. The virus has been repeatedly detected in dromedary camels (Camelus dromedarius). Adult animals in many countries in the Middle East as well as in North and East Africa showed high (>90%) seroprevalence to the virus. Middle East respiratory syndrome coronavirus isolated from dromedaries is genetically and phenotypically similar to viruses from humans. We summarize current understanding of the ecology of MERS‐CoV in animals and transmission at the animal–human interface. We review aspects of husbandry, animal movements and trade and the use and consumption of camel dairy and meat products in the Middle East that may be relevant to the epidemiology of MERS. We also highlight the gaps in understanding the transmission of this virus in animals and from animals to humans.

Animal models of Middle East respiratory syndrome coronavirus infection

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MERS-CoV has infected >1100 patients to date, with an associated case fatality rate of approximately 40%.

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Animals ranging from mice to rabbits to nonhuman primates have been inoculated with MERS-CoV, with varying outcomes.

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Mice expressing human DPP4 are susceptible to infection and develop severe disease.

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Rhesus macaques and marmosets are also susceptible, but marmosets develop more severe disease.

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Further development of appropriate animal models to conduct medical countermeasure research is a public health priority.

The emergence of the Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012 marked the second time that a new, highly pathogenic coronavirus has emerged in the human population in the 21st century. In this review, we discuss the current state of knowledge of animal models of MERS-CoV infection. Commonly used laboratory animal species such as Syrian hamsters, mice and ferrets are not susceptible to MERS-CoV, due to differences in the MERS-CoV receptor dipeptidyl peptidase 4 (DPP4). The initially developed animal models comprise two nonhuman primate species, the rhesus macaque and the common marmoset. Rhesus macaques develop a mild to moderate respiratory disease upon inoculation, reminiscent of milder MERS cases, whereas marmosets develop a moderate to severe respiratory disease, recapitulating the severe disease observed in some patients. Dromedary camels, considered to be the reservoir for MERS-CoV, develop a mild upper respiratory tract infection with abundant viral shedding. Although normal mice are not susceptible to MERS-CoV, expression of the human DPP4 (hDPP4) overcomes the lack of susceptibility. Transgenic hDPP4 mice develop severe and lethal respiratory disease upon inoculation with MERS-CoV. These hDPP4 transgenic mice are potentially the ideal first line animal model for efficacy testing of therapeutic and prophylactic countermeasures. Further characterization of identified countermeasures would ideally be performed in the common marmoset model, due to the more severe disease outcome. This article forms part of a symposium in Antiviral Research on “From SARS to MERS: research on highly pathogenic human coronaviruses.”

A novel astrovirus from dromedaries in the Middle East

The recent emergence of Middle East respiratory syndrome coronavirus from the Middle East and its discovery from dromedary camels has boosted interest in the search for novel viruses in dromedaries. The existence of astroviruses (AstVs) in dromedaries was previously unknown. We describe the discovery of a novel dromedary camel AstV (DcAstV) from dromedaries in Dubai. Among 215 dromedaries, DcAstV was detected in faecal samples of four [three (1.5 %) adult dromedaries and one (8.3 %) dromedary calf] by reverse transcription-PCR. Sequencing of the four DcAstV genomes and phylogenetic analysis showed that the DcAstVs formed a distinct cluster. Although DcAstV was most closely related to a recently characterized porcine AstV 2, their capsid proteins only shared 60-66 % amino acid identity, with a mean amino acid genetic distance of 0.372. Notably, the N-terminal halves of the capsid proteins of DcAstV shared ≤ 85 % amino acid identity, but the C-terminal halves only shared ≤ 49 % amino acid identity compared with the corresponding proteins in other AstVs. A high variation of the genome sequences of DcAstV was also observed, with a mean amino acid genetic distance of 0.214 for ORF2 of the four strains. Recombination analysis revealed a possible recombination event in ORF2 of strain DcAstV-274. The low Ka/Ks ratios (number of non-synonymous substitutions per non-synonymous site to number of synonymous substitutions per synonymous site) of the four ORFs in the DcAstV genomes supported the suggestion that dromedaries are the natural reservoir where AstV is stably evolving. These results suggest that AstV is a novel species of the genus Mamastrovirus in the family Astroviridae. Further studies are important to understand the pathogenic potential of DcAstV.

MERS-CoV in Upper Respiratory Tract and Lungs of Dromedary Camels, Saudi Arabia, 2013-2014

To assess the temporal dynamics of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in dromedary camels, specimens were collected at 1-2 month intervals from 2 independent groups of animals during April 2013-May 2014 in Al-Ahsa Province, Saudi Arabia, and tested for MERS-CoV RNA by reverse transcription PCR. Of 96 live camels, 28 (29.2%) nasal swab samples were positive; of 91 camel carcasses, 56 (61.5%) lung tissue samples were positive. Positive samples were more commonly found among young animals (<4 years of age) than adults (>4 years of age). The proportions of positive samples varied by month for both groups; detection peaked during November 2013 and January 2014 and declined in March and May 2014. These findings further our understanding of MERS-CoV infection in dromedary camels and may help inform intervention strategies to reduce zoonotic infections.

Middle East respiratory syndrome: obstacles and prospects for vaccine development

The recent emergence of Middle East respiratory syndrome (MERS) highlights the need to engineer new methods for expediting vaccine development against emerging diseases. However, several obstacles prevent pursuit of a licensable MERS vaccine. First, the lack of a suitable animal model for MERS complicates the in vivo testing of candidate vaccines. Second, due to the low number of MERS cases, pharmaceutical companies have little incentive to pursue MERS vaccine production as the costs of clinical trials are high. In addition, the timeline from bench research to approved vaccine use is 10 years or longer. Using novel methods and cost-saving strategies, genetically engineered vaccines can be produced quickly and cost-effectively. Along with progress in MERS animal model development, these obstacles can be circumvented or at least mitigated.

Therapeutic Options for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Infection: How Close Are We?

Over 1100 cases of MERS-CoV have been reported since it was first identified in June 2012. Clinical presentation ranges from asymptomatic or mild illness to rapidly progressive disease with multi-organ failure and high mortality. Treatment has been largely supportive. A large number of compounds have been shown to have significant in vitro inhibitory activity against MERS-CoV. Until recently, macaques were the only suitable animal models for animal studies, hindering further clinical development of MERS-CoV therapy. However, the recent successful development of MERS-CoV infection model in transduced mice offers opportunities to accelerate clinical development of therapeutic agents for MERS-CoV infection. Currently available evidence supports further clinical investigation of interferon-based treatment regimens for patients with MERS-CoV. Combining interferon with mycophenolate and/or high-dose ribavirin appears especially promising. Monoclonal antibodies against various targets within MERS-CoV Spike protein have yielded encouraging in-vitro results. However, their safety and efficacy require confirmation in animal models and exploratory clinical trials.

Middle East respiratory syndrome coronavirus "MERS-CoV": current knowledge gaps

The Middle East respiratory syndrome coronavirus (MERS-CoV) that causes a severe lower respiratory tract infection in humans is now considered a pandemic threat to the Gulf region. Since its discovery in 2012, MERS-CoV has reached 23 countries affecting about 1100 people, including a dozen children, and claiming over 400 lives. Compared to SARS (severe acute respiratory syndrome), MERS-CoV appears to kill more people (40% versus 10%), more quickly, and is especially more severe in those with pre-existing medical conditions. Most MERS-CoV cases (>85%) reported thus far have a history of residence in, or travel to the Middle East. The current epidemiology is characterised by slow and sustained transmission with occasional sparks. The dromedary camel is the intermediate host of MERS-CoV, but the transmission cycle is not fully understood. In this current review, we have briefly summarised the latest information on the epidemiology, clinical features, diagnosis, treatment and prevention of MERS-CoV especially highlighting the knowledge gaps in its transmission dynamics, diagnosis and preventive strategy.

Coronaviruses: severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus in travelers

PURPOSE OF REVIEW

Middle East respiratory syndrome coronavirus (MERS-CoV) is currently the focus of global attention. In this review, we describe virological, clinical, epidemiological features and interim travel advice and guidelines regarding MERS-CoV. We compare and contrast these with the severe acute respiratory syndrome coronavirus (SARS-CoV).

RECENT FINDINGS

MERS-CoV is a novel β CoV that causes a spectrum of clinical illness from asymptomatic to the rapidly fatal disease mainly in those with comorbid conditions. Epidemiological and genomic studies show zoonotic transmission to humans from camels and possibly bats. In contrast to the SARS-CoV pandemic, very limited global spread of fatal MERS-CoV has occurred outside the Arabian Peninsula. Although mainly currently restricted to Middle Eastern countries, MERS-CoV was reported from at least 10 other countries in Europe, Asia and the United States. All primary cases have been linked to travel to the Middle East. Nosocomial transmission of MERS-CoV has occurred because of poor infection control measures. Specific molecular diagnostic tests are available. Currently, there are no specific drugs for prevention or treatment for MERS-CoV and vaccine development is in the early stages. Advice and guidance for travelers to the Middle East are updated regularly by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC).

SUMMARY

Like SARS-CoV, MERS-CoV threatens global health security. All physicians and travelers to the Middle East should be aware of the new threat caused by MERS-CoV and follow CDC and WHO guidelines. Those who develop ill health during their trip or soon after their return should seek medical care.

Development of animal models against emerging coronaviruses: From SARS to MERS coronavirus

Two novel coronaviruses have emerged to cause severe disease in humans. While bats may be the primary reservoir for both viruses, SARS coronavirus (SARS-CoV) likely crossed into humans from civets in China, and MERS coronavirus (MERS-CoV) has been transmitted from camels in the Middle East. Unlike SARS-CoV that resolved within a year, continued introductions of MERS-CoV present an on-going public health threat. Animal models are needed to evaluate countermeasures against emerging viruses. With SARS-CoV, several animal species were permissive to infection. In contrast, most laboratory animals are refractory or only semi-permissive to infection with MERS-CoV. This host-range restriction is largely determined by sequence heterogeneity in the MERS-CoV receptor. We describe animal models developed to study coronaviruses, with a focus on host-range restriction at the level of the viral receptor and discuss approaches to consider in developing a model to evaluate countermeasures against MERS-CoV.

A sensitive and specific antigen detection assay for Middle East respiratory syndrome coronavirus

Since its emergence in 2012, more than 900 laboratory-confirmed cases of Middle East respiratory syndrome (MERS) have been reported with a fatality rate of more than 30%. However, no antigen detection assay for commercial use is available for diagnosis. In this study, the full-length nucleocapsid protein (NP) gene of MERS coronavirus (MERS-CoV) was cloned and expressed in Escherichia coli. A MERS-CoV NP capture enzyme-linked immunosorbent assay (ELISA) using two MERS-CoV-NP-specific monoclonal antibodies (MAbs) generated was developed. The ELISA was evaluated using 129 nasopharyngeal aspirates (NPAs) positive for various respiratory viruses and simulated positive NPAs by adding serial dilutions of MERS-CoV. Using a cutoff OD of 0.19, all 129 NPAs positive for respiratory viruses showed very low OD, with a specificity of 100%. For the two simulated MERS-CoV-positive NPAs with serial dilutions of live MERS-CoV, all samples with ≥10 50% tissue culture infective dose (TCID50)/0.1 mL showed positive results. For the 10 additional NPAs with 20 and 200 TCID50/0.1 mL of live MERS-CoV added, all were positive. A highly sensitive and specific MAbs-based antigen capture ELISA has been developed for MERS. This sensitive and specific antigen capture ELISA should be useful for detection of MERS-CoV in human and dromedaries and in field studies.

Middle East respiratory syndrome coronavirus: another zoonotic betacoronavirus causing SARS-like disease

The source of the severe acute respiratory syndrome (SARS) epidemic was traced to wildlife market civets and ultimately to bats. Subsequent hunting for novel coronaviruses (CoVs) led to the discovery of two additional human and over 40 animal CoVs, including the prototype lineage C betacoronaviruses, Tylonycteris bat CoV HKU4 and Pipistrellus bat CoV HKU5; these are phylogenetically closely related to the Middle East respiratory syndrome (MERS) CoV, which has affected more than 1,000 patients with over 35% fatality since its emergence in 2012. All primary cases of MERS are epidemiologically linked to the Middle East. Some of these patients had contacted camels which shed virus and/or had positive serology. Most secondary cases are related to health care-associated clusters. The disease is especially severe in elderly men with comorbidities. Clinical severity may be related to MERS-CoV's ability to infect a broad range of cells with DPP4 expression, evade the host innate immune response, and induce cytokine dysregulation. Reverse transcription-PCR on respiratory and/or extrapulmonary specimens rapidly establishes diagnosis. Supportive treatment with extracorporeal membrane oxygenation and dialysis is often required in patients with organ failure. Antivirals with potent in vitro activities include neutralizing monoclonal antibodies, antiviral peptides, interferons, mycophenolic acid, and lopinavir. They should be evaluated in suitable animal models before clinical trials. Developing an effective camel MERS-CoV vaccine and implementing appropriate infection control measures may control the continuing epidemic.

Middle East respiratory syndrome: An emerging coronavirus infection tracked by the crowd

In 2012 in Jordan, infection by a novel coronavirus (CoV) caused the first known cases of Middle East respiratory syndrome (MERS). MERS-CoV sequences have since been found in a bat and the virus appears to be enzootic among dromedary camels across the Arabian Peninsula and in parts of Africa. The majority of human cases have occurred in the Kingdom of Saudi Arabia (KSA). In humans, the etiologic agent, MERS-CoV, has been detected in severe, mild and influenza-like illness and in those without any obvious signs or symptoms of disease. MERS is often a lower respiratory tract disease associated with fever, cough, breathing difficulties, pneumonia that can progress to acute respiratory distress syndrome, multiorgan failure and death among more than a third of those infected. Severe disease is usually found in older males and comorbidities are frequently present in cases of MERS. Compared to SARS, MERS progresses more rapidly to respiratory failure and acute kidney injury, is more often observed as severe disease in patients with underlying illnesses and is more often fatal. MERS-CoV has a broader tropism than SARS-CoV, rapidly triggers cellular damage, employs a different receptor and induces a delayed proinflammatory response in cells. Most human cases have been linked to lapses in infection prevention and control in healthcare settings, with a fifth of virus detections reported among healthcare workers. This review sets out what is currently known about MERS and the MERS-CoV, summarises the new phenomenon of crowd-sourced epidemiology and lists some of the many questions that remain unanswered, nearly three years after the first reported case.

Middle East Respiratory Syndrome Corona Virus (MERS CoV): The next steps

Developing countries are at risk of importing Middle East Respiratory Syndrome Corona Virus (MERS CoV) from the Middle East. Hospitals in the Middle East currently reporting the disease are staffed by immigrants. In the current hot spots for MERS CoV a sizeable portion of the population is from other countries, but many of these countries have yet to detect any importation of MERS CoV. To assess the disease transmission in these countries, supplemental surveillance strategies are urgently needed beyond the currently recommended measures. A few strategies to address the situation are: (i) improving preparedness with enhanced surveillance in particular regions; (ii) targeting certain sentinel groups for surveillance in hot spots; and (iii) limited use of serosurveillance. Recovered, immune patients can be employed to give patient care during outbreaks.

A novel dromedary camel enterovirus in the family Picornaviridae from dromedaries in the Middle East

The recent emergence of Middle East respiratory syndrome coronavirus from the Middle East and the discovery of the virus from dromedary camels have boosted interest in the search for novel viruses in dromedaries. Whilst picornaviruses are known to infect various animals, their existence in dromedaries was unknown. We describe the discovery of a novel picornavirus, dromedary camel enterovirus (DcEV), from dromedaries in Dubai. Among 215 dromedaries, DcEV was detected in faecal samples of four (1.9 %) dromedaries [one (0.5 %) adult dromedary and three (25 %) dromedary calves] by reverse transcription PCR. Analysis of two DcEV genomes showed that DcEV was clustered with other species of the genus Enterovirus and was most closely related to and possessed highest amino acid identities to the species Enterovirus E and Enterovirus F found in cattle. The G+C content of DcEV was 45 mol%, which differed from that of Enterovirus E and Enterovirus F (49-50 mol%) by 4-5 %. Similar to other members of the genus Enterovirus, the 5' UTR of DcEV possessed a putative type I internal ribosome entry site. The low ratios of the number of nonsynonymous substitutions per non-synonymous site to the number of synonymous substitutions per synonymous site (Ka/Ks) of various coding regions suggested that dromedaries are the natural reservoir in which DcEV has been stably evolving. These results suggest that DcEV is a novel species of the genus Enterovirus in the family Picornaviridae. Western blot analysis using recombinant DcEV VP1 polypeptide showed a high seroprevalence of 52 % among serum samples from 172 dromedaries for IgG, concurring with its much higher infection rates in dromedary calves than in adults. Further studies are important to understand the pathogenicity, epidemiology and genetic evolution of DcEV in this unique group of animals.

An update on Middle East respiratory syndrome: 2 years later

Middle East respiratory syndrome coronavirus (MERS-CoV) was first recognized in 2012 and since then has resulted in cases in 23 countries in four continents. The majority of these cases were reported from the Kingdom of Saudi Arabia. The disease caused a spectrum of illness, from asymptomatic to severe and possibly fatal disease. Recent studies showed that the transmission of MERS-CoV among family contacts remains relatively low. Currently, there are no approved vaccines or therapeutics for MERS-CoV.

MERS coronavirus in dromedary camel herd, Saudi Arabia

A prospective study of a dromedary camel herd during the 2013–14 calving season showed Middle East respiratory syndrome coronavirus infection of calves and adults. Virus was isolated from the nose and feces but more frequently from the nose. Preexisting neutralizing antibody did not appear to protect against infection.

Human infection with MERS coronavirus after exposure to infected camels, Saudi Arabia, 2013

We investigated a case of human infection with Middle East respiratory syndrome coronavirus (MERS-CoV) after exposure to infected camels. Analysis of the whole human-derived virus and 15% of the camel-derived virus sequence yielded nucleotide polymorphism signatures suggestive of cross-species transmission. Camels may act as a direct source of human MERS-CoV infection.

MERS coronaviruses in dromedary camels, Egypt

We identified the near-full-genome sequence (29,908 nt, >99%) of Middle East respiratory syndrome coronavirus (MERS-CoV) from a nasal swab specimen from a dromedary camel in Egypt. We found that viruses genetically very similar to human MERS-CoV are infecting dromedaries beyond the Arabian Peninsula, where human MERS-CoV infections have not yet been detected.

Human-Dromedary Camel Interactions and the Risk of Acquiring Zoonotic Middle East Respiratory Syndrome Coronavirus Infection

Middle East respiratory syndrome coronavirus (MERS‐CoV) cases without documented contact with another human MERS‐CoV case make up 61% (517/853) of all reported cases. These primary cases are of particular interest for understanding the source(s) and route(s) of transmission and for designing long‐term disease control measures. Dromedary camels are the only animal species for which there is convincing evidence that it is a host species for MERS‐CoV and hence a potential source of human infections. However, only a small proportion of the primary cases have reported contact with camels. Other possible sources and vehicles of infection include food‐borne transmission through consumption of unpasteurized camel milk and raw meat, medicinal use of camel urine and zoonotic transmission from other species. There are critical knowledge gaps around this new disease which can only be closed through traditional field epidemiological investigations and studies designed to test hypothesis regarding sources of infection and risk factors for disease. Since the 1960s, there has been a radical change in dromedary camel farming practices in the Arabian Peninsula with an intensification of the production and a concentration of the production around cities. It is possible that the recent intensification of camel herding in the Arabian Peninsula has increased the virus' reproductive number and attack rate in camel herds while the ‘urbanization’ of camel herding increased the frequency of zoonotic ‘spillover’ infections from camels to humans. It is reasonable to assume, although difficult to measure, that the sensitivity of public health surveillance to detect previously unknown diseases is lower in East Africa than in Saudi Arabia and that sporadic human cases may have gone undetected there.

Middle East respiratory syndrome coronavirus (MERS-CoV) entry inhibitors targeting spike protein

The recent outbreak of Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) infection has led to more than 800 laboratory-confirmed MERS cases with a high case fatality rate (∼35%), posing a serious threat to global public health and calling for the development of effective and safe therapeutic and prophylactic strategies to treat and prevent MERS-CoV infection. Here we discuss the most recent studies on the structure of the MERS-CoV spike protein and its role in virus binding and entry, and the development of MERS-CoV entry/fusion inhibitors targeting the S1 subunit, particularly the receptor-binding domain (RBD), and the S2 subunit, especially the HR1 region, of the MERS-CoV spike protein. We then look ahead to future applications of these viral entry/fusion inhibitors, either alone or in combination with specific and nonspecific MERS-CoV replication inhibitors, for the treatment and prevention of MERS-CoV infection.

Development of human neutralizing monoclonal antibodies for prevention and therapy of MERS-CoV infections

The recent Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak poses a serious threat to public health. Here, we summarize recent advances in identifying human neutralizing monoclonal antibodies (mAbs) against MERS-CoV, describe their mechanisms of action, and analyze their potential for treatment of MERS-CoV infections.

CD26/DPP4 cell-surface expression in bat cells correlates with bat cell susceptibility to Middle East respiratory syndrome coronavirus (MERS-CoV) infection and evolution of persistent infection

Middle East respiratory syndrome coronavirus (MERS-CoV) is a recently isolated betacoronavirus identified as the etiologic agent of a frequently fatal disease in Western Asia, Middle East respiratory syndrome. Attempts to identify the natural reservoirs of MERS-CoV have focused in part on dromedaries. Bats are also suspected to be reservoirs based on frequent detection of other betacoronaviruses in these mammals. For this study, ten distinct cell lines derived from bats of divergent species were exposed to MERS-CoV. Plaque assays, immunofluorescence assays, and transmission electron microscopy confirmed that six bat cell lines can be productively infected. We found that the susceptibility or resistance of these bat cell lines directly correlates with the presence or absence of cell surface-expressed CD26/DPP4, the functional human receptor for MERS-CoV. Human anti-CD26/DPP4 antibodies inhibited infection of susceptible bat cells in a dose-dependent manner. Overexpression of human CD26/DPP4 receptor conferred MERS-CoV susceptibility to resistant bat cell lines. Finally, sequential passage of MERS-CoV in permissive bat cells established persistent infection with concomitant downregulation of CD26/DPP4 surface expression. Together, these results imply that bats indeed could be among the MERS-CoV host spectrum, and that cellular restriction of MERS-CoV is determined by CD26/DPP4 expression rather than by downstream restriction factors.

Middle East respiratory syndrome coronavirus: epidemiology and disease control measures

The emergence of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in 2012 resulted in an increased concern of the spread of the infection globally. MERS-CoV infection had previously caused multiple health-care-associated outbreaks and resulted in transmission of the virus within families. Community onset MERS-CoV cases continue to occur. Dromedary camels are currently the most likely animal to be linked to human MERS-CoV cases. Serologic tests showed significant infection in adult camels compared to juvenile camels. The control of MERS-CoV infection relies on prompt identification of cases within health care facilities, with institutions applying appropriate infection control measures. In addition, determining the exact route of transmission from camels to humans would further add to the control measures of MERS-CoV infection.

Emerging viral respiratory tract infections--environmental risk factors and transmission

The past decade has seen the emergence of several novel viruses that cause respiratory tract infections in human beings, including Middle East respiratory syndrome coronavirus (MERS-CoV) in Saudi Arabia, an H7N9 influenza A virus in eastern China, a swine-like influenza H3N2 variant virus in the USA, and a human adenovirus 14p1 also in the USA. MERS-CoV and H7N9 viruses are still a major worldwide public health concern. The pathogenesis and mode of transmission of MERS-CoV and H7N9 influenza A virus are poorly understood, making it more difficult to implement intervention and preventive measures. A united and coordinated global response is needed to tackle emerging viruses that can cause fatal respiratory tract infections and to fill major gaps in the understanding of the epidemiology and transmission dynamics of these viruses.

Travel-related MERS-CoV cases: an assessment of exposures and risk factors in a group of Dutch travellers returning from the Kingdom of Saudi Arabia, May 2014

BACKGROUND

In May 2014, Middle East respiratory syndrome coronavirus (MERS-CoV) infection, with closely related viral genomes, was diagnosed in two Dutch residents, returning from a pilgrimage to Medina and Mecca, Kingdom of Saudi Arabia (KSA). These patients travelled with a group of 29 other Dutch travellers. We conducted an epidemiological assessment of the travel group to identify likely source(s) of infection and presence of potential risk factors.

METHODS

All travellers, including the two cases, completed a questionnaire focussing on potential human, animal and food exposures to MERS-CoV. The questionnaire was modified from the WHO MERS-CoV questionnaire, taking into account the specific route and activities of the travel group.

RESULTS

Twelve non-cases drank unpasteurized camel milk and had contact with camels. Most travellers, including one of the two patients (Case 1), visited local markets, where six of them consumed fruits. Two travellers, including Case 1, were exposed to coughing patients when visiting a hospital in Medina. Four travellers, including Case 1, visited two hospitals in Mecca. All travellers had been in contact with Case 1 while he was sick, with initially non-respiratory complaints. The cases were found to be older than the other travellers and both had co-morbidities.

CONCLUSIONS

This epidemiological study revealed the complexity of MERS-CoV outbreak investigations with multiple potential exposures to MERS-CoV reported such as healthcare visits, camel exposure, and exposure to untreated food products. Exposure to MERS-CoV during a hospital visit is considered a likely source of infection for Case 1 but not for Case 2. For Case 2, the most likely source could not be determined. Exposure to MERS-CoV via direct contact with animals or dairy products seems unlikely for the two Dutch cases. Furthermore, exposure to a common but still unidentified source cannot be ruled out. More comprehensive research into sources of infection in the Arabian Peninsula is needed to strengthen and specify the prevention of MERS-CoV infections.

Immunogenicity of an adenoviral-based Middle East Respiratory Syndrome coronavirus vaccine in BALB/c mice

A new type of coronavirus has been identified as the causative agent underlying Middle East Respiratory Syndrome (MERS). The MERS coronavirus (MERS-CoV) has spread in the Middle East, but cases originating in the Middle East have also occurred in the European Union and the USA. Eight hundred and thirty-seven cases of MERS-CoV infection have been confirmed to date, including 291 deaths. MERS-CoV has infected dromedary camel populations in the Middle East at high rates, representing an immediate source of human infection. The MERS-CoV spike (S) protein, a characteristic structural component of the viral envelope, is considered as a key target of vaccines against coronavirus infection. In an initial attempt to develop a MERS-CoV vaccine to ultimately target dromedary camels, we constructed two recombinant adenoviral vectors encoding the full-length MERS-CoV S protein (Ad5.MERS-S) and the S1 extracellular domain of S protein (Ad5.MERS-S1). BALB/c mice were immunized with both candidate vaccines intramuscularly and boosted three weeks later intranasally. All the vaccinated animals had antibody responses against spike protein, which neutralized MERS-CoV in vitro. These results show that an adenoviral-based vaccine can induce MERS-CoV-specific immune responses in mice and hold promise for the development of a preventive vaccine that targets the animal reservoir, which might be an effective measure to eliminate transmission of MERS-CoV to humans.

Virological and serological analysis of a recent Middle East respiratory syndrome coronavirus infection case on a triple combination antiviral regimen

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Serological, molecular and phylogenetic analysis of a recently imported case of MERS coronavirus (MERS-CoV) in Greece.

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MERS-CoV remained detectable in the respiratory tract secretions of the patient until the fourth week of illness, whereas viraemia was last detected two days after the institution of the triple combination therapy.

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The non-detectable viral RNA in serum by day 3 after the initiation of the antiviral treatment could be explained either by viral clearance in an otherwise immunocompetent person or by effectiveness of the instituted antiviral regimen.

Serological, molecular and phylogenetic analyses of a recently imported case of Middle East respiratory syndrome coronavirus (MERS-CoV) in Greece are reported. Although MERS-CoV remained detectable in the respiratory tract secretions of the patient until the fourth week of illness, viraemia was last detected 2 days after initiation of triple combination therapy with pegylated interferon, ribavirin and lopinavir/ritonavir, administered from Day 13 of illness. Phylogenetic analysis of the virus showed close similarity with other human MERS-CoVs from the recent Jeddah outbreak in Saudi Arabia. Immunoglobulin G (IgG) titres peaked 3 weeks after the onset of illness, whilst IgM levels remained constantly elevated during the follow-up period (second to fifth week of illness). Serological testing confirmed by virus neutralisation assay detected an additional case that was a close contact of the patient.

Rapid point of care diagnostic tests for viral and bacterial respiratory tract infections--needs, advances, and future prospects

Respiratory tract infections rank second as causes of adult and paediatric morbidity and mortality worldwide. Respiratory tract infections are caused by many different bacteria (including mycobacteria) and viruses, and rapid detection of pathogens in individual cases is crucial in achieving the best clinical management, public health surveillance, and control outcomes. Further challenges in improving management outcomes for respiratory tract infections exist: rapid identification of drug resistant pathogens; more widespread surveillance of infections, locally and internationally; and global responses to infections with pandemic potential. Developments in genome amplification have led to the discovery of several new respiratory pathogens, and sensitive PCR methods for the diagnostic work-up of these are available. Advances in technology have allowed for development of single and multiplexed PCR techniques that provide rapid detection of respiratory viruses in clinical specimens. Microarray-based multiplexing and nucleic-acid-based deep-sequencing methods allow simultaneous detection of pathogen nucleic acid and multiple antibiotic resistance, providing further hope in revolutionising rapid point of care respiratory tract infection diagnostics.

Travel implications of emerging coronaviruses: SARS and MERS-CoV

The emergence of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and of the Middle East Syndrome Cornavirus (MERS-CoV) caused widespread fear and concern for their potential threat to global health security. There are similarities and differences in the epidemiology and clinical features between these two diseases. The origin of SARS-COV and MERS-CoV is thought to be an animal source with subsequent transmission to humans. The identification of both the intermediate host and the exact route of transmission of MERS-CoV is crucial for the subsequent prevention of the introduction of the virus into the human population. So far MERS-CoV had resulted in a limited travel-associated human cases with no major events related to the Hajj.

Middle East respiratory syndrome coronavirus: transmission and phylogenetic evolution

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MERS-CoV continues to cause sporadic cases with amplification of cases in the healthcare setting.

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Camels have been linked as an intermediate host.

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Proper infection control measures are needed to prevent nosocomial outbreaks.

The Middle East respiratory syndrome coronavirus (MERS-CoV) was first described in 2012 and, subsequently, many cases were reported with a lower case fatality rate than initial cases. Humans can become infected within their communities and transmission can then be amplified in the healthcare setting. Contact investigation among cases shows a variable amount of spread among family members and healthcare workers. So far, circulating virus strains remain similar under continuous monitoring, with no genetic changes. Here, we discuss the transmission pattern, phylogenetic evolution, and pathogenesis of MERS-CoV infection.

Transmission of MERS-coronavirus in household contacts

BACKGROUND

Strategies to contain the Middle East respiratory syndrome coronavirus (MERS-CoV) depend on knowledge of the rate of human-to-human transmission, including subclinical infections. A lack of serologic tools has hindered targeted studies of transmission.

METHODS

We studied 26 index patients with MERS-CoV infection and their 280 household contacts. The median time from the onset of symptoms in index patients to the latest blood sampling in contact patients was 17.5 days (range, 5 to 216; mean, 34.4). Probable cases of secondary transmission were identified on the basis of reactivity in two reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assays with independent RNA extraction from throat swabs or reactivity on enzyme-linked immunosorbent assay against MERS-CoV S1 antigen, supported by reactivity on recombinant S-protein immunofluorescence and demonstration of neutralization of more than 50% of the infectious virus seed dose on plaque-reduction neutralization testing.

RESULTS

Among the 280 household contacts of the 26 index patients, there were 12 probable cases of secondary transmission (4%; 95% confidence interval, 2 to 7). Of these cases, 7 were identified by means of RT-PCR, all in samples obtained within 14 days after the onset of symptoms in index patients, and 5 were identified by means of serologic analysis, all in samples obtained 13 days or more after symptom onset in index patients. Probable cases of secondary transmission occurred in 6 of 26 clusters (23%). Serologic results in contacts who were sampled 13 days or more after exposure were similar to overall study results for combined RT-PCR and serologic testing.

CONCLUSIONS

The rate of secondary transmission among household contacts of patients with MERS-CoV infection has been approximately 5%. Our data provide insight into the rate of subclinical transmission of MERS-CoV in the home.

Detection of Middle East respiratory syndrome coronavirus using reverse transcription loop-mediated isothermal amplification (RT-LAMP)

Background

The first documented case of Middle East Respiratory Syndrome coronavirus (MERS-CoV) occurred in 2012, and outbreaks have continued ever since, mainly in Saudi Arabia. MERS-CoV is primarily diagnosed using a real-time RT-PCR assay, with at least two different genomic targets required for a positive diagnosis according to the case definition of The World Health Organization (WHO) as of 3 July 2013. Therefore, it is urgently necessary to develop as many specific genetic diagnostic methods as possible to allow stable diagnosis of MERS-CoV infections.

Methods

Reverse transcription-loop-mediated isothermal amplification (RT-LAMP) is a genetic diagnostic method used widely for the detection of viral pathogens, which requires only a single temperature for amplification, and can be completed in less than 1 h. This study developed a novel RT-LAMP assay for detecting MERS-CoV using primer sets targeting a conserved nucleocapsid protein region.

Results

The RT-LAMP assay was capable of detecting as few as 3.4 copies of MERS-CoV RNA, and was highly specific, with no cross-reaction to other respiratory viruses. Pilot experiments to detect MERS-CoV from medium containing pharyngeal swabs inoculated with pre-titrated viruses were also performed. The RT-LAMP assay exhibited sensitivity similar to that of MERS-CoV real-time RT-PCR.

Conclusions

These results suggest that the RT-LAMP assay described here is a useful tool for the diagnosis and epidemiologic surveillance of human MERS-CoV infections.

Geographic distribution of MERS coronavirus among dromedary camels, Africa

We found serologic evidence for the circulation of Middle East respiratory syndrome coronavirus among dromedary camels in Nigeria, Tunisia, and Ethiopia. Circulation of the virus among dromedaries across broad areas of Africa may indicate that this disease is currently underdiagnosed in humans outside the Arabian Peninsula.

A scenario-based evaluation of the Middle East respiratory syndrome coronavirus and the Hajj

Between April 2012 and June 2014, 820 laboratory-confirmed cases of the Middle East respiratory syndrome coronavirus (MERS-CoV) have been reported in the Arabian Peninsula, Europe, North Africa, Southeast Asia, the Middle East, and the United States. The observed epidemiology is different to SARS, which showed a classic epidemic curve and was over in eight months. The much longer persistence of MERS-CoV in the population, with a lower reproductive number, some evidence of human-to-human transmission but an otherwise sporadic pattern, is difficult to explain. Using available epidemiological data, we implemented mathematical models to explore the transmission dynamics of MERS-CoV in the context of mass gatherings such as the Hajj pilgrimage, and found a discrepancy between the observed and expected epidemiology. The fact that no epidemic occurred in returning Hajj pilgrims in either 2012 or 2013 contradicts the long persistence of the virus in human populations. The explanations for this discrepancy include an ongoing, repeated nonhuman/sporadic source, a large proportion of undetected or unreported human-to-human cases, or a combination of the two. Furthermore, MERS-CoV is occurring in a region that is a major global transport hub and hosts significant mass gatherings, making it imperative to understand the source and means of the yet unexplained and puzzling ongoing persistence of the virus in the human population.

The emergence of the Middle East respiratory syndrome coronavirus

On September 20, 2012, a Saudi Arabian physician reported the isolation of a novel coronavirus from a patient with pneumonia on ProMED-mail. Within a few days, the same virus was detected in a Qatari patient receiving intensive care in a London hospital, a situation reminiscent of the role air travel played in the spread of severe acute respiratory syndrome coronavirus (SARS-CoV) in 2002. SARS-CoV originated in China's Guangdong Province and affected more than 8000 patients in 26 countries before it was contained 6 months later. Over a year after the emergence of this novel coronavirus--Middle East respiratory syndrome coronavirus (MERS-CoV)--it has caused 178 laboratory-confirmed cases and 76 deaths. The emergence of a second highly pathogenic coronavirus within a decade highlights the importance of a coordinated global response incorporating reservoir surveillance, high-containment capacity with fundamental and applied research programs, and dependable communication pathways to ensure outbreak containment. Here, we review the current state of knowledge on the epidemiology, ecology, molecular biology, clinical features, and intervention strategies of the novel coronavirus, MERS-CoV.