Healthcare providers should maintain awareness of the need to detect patients who should be evaluated for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection; this requires clinical judgment as information on modes of transmission of MERS-CoV and clinical presentation of MERS continues to evolve.

The spectrum of illness due to MERS-CoV infection is not fully defined. Symptoms of MERS-CoV infections are typically non-specific. At hospital admission, common signs and symptoms include fever, chills/rigors, headache, non-productive cough, dyspnea, and myalgia. Other symptoms can include sore throat, coryza, sputum production, dizziness, nausea and vomiting, diarrhea, and abdominal pain. Atypical presentations including mild respiratory illness without fever and diarrheal illness preceding development of pneumonia have been reported. Clinical judgment should be used to guide testing of patients for MERS-CoV infection.

Patients in the U.S. Who Should Be Evaluated for MERS-CoV Infection

Healthcare providers should evaluate patients in the U.S. for MERS-CoV infection if they meet the following criteria, defined as a Person Under Investigation (PUI)

 

The above criteria serve as guidance for testing; however, patients should be evaluated and discussed with public health departments on a case-by-case basis if their clinical presentation or exposure history is equivocal (e.g., uncertain history of health care exposure).

Confirmed Case

A confirmed case is a person with laboratory confirmation of MERS-CoV infection. Confirmatory laboratory testing requires a positive PCR on at least two specific genomic targets or a single positive target with sequencing on a second.

Probable Case

A probable case is a PUI with absent or inconclusive laboratory results for MERS-CoV infection who is a close contact³ of a laboratory-confirmed MERS-CoV case. Examples of laboratory results that may be considered inconclusive include a positive test on a single PCR target, a positive test with an assay that has limited performance data available, or a negative test on an inadequate specimen.

Reporting Persons Under Investigation (PUIs)

Update July 2017:

To simplify the process, MERS reporting to CDC has been updated:

• CDC is no longer asking for state and local health departments to submit MERS short forms for PUIs who test negative for MERS-CoV.
• State and local health departments must still submit all CDC MERS-CoV rRT-PCR assay test results (e.g., negative, positive, equivocal) via the LRN. Any MERS case detected in the U.S., and any PUI with equivocal or positive MERS test results must still be immediately reported to CDC as currently recommended.
• CDC staff will continue to remain available for epidemiologic and laboratory consultation for MERS. Please contact eocreport@cdc.gov with any questions about MERS PUIs or MERS-CoV testing, or call the CDC Emergency Operations Center (EOC) at 770-488-7100
• MERS PUI short forms are still available to use as tools when investigating PUIs.

• Download PDF file [1 page]
• Download Microsoft Word file [1 page]

• NOTE: CDC may revise optional submission of the MERS short form for PUIs who test negative for MERS-CoV in the future if circumstances change, such as increasing worldwide MERS cases or if a MERS case is identified in the U.S.

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Evaluation and Management of Close Contacts

CLOSE CONTACTS OF A CONFIRMED CASE

As part of investigation of confirmed cases, in consultation with a state or local health department, a person who develops fever¹ or symptoms of respiratory illness within 14 days following close contact³ with a confirmed case of MERS while the case was ill should be evaluated for MERS-CoV infection.

Other contacts of the ill person, such as community contacts or contacts on conveyances (e.g., airplane, bus), may be considered for evaluation in consultation with state and local health departments.

Clinicians should be aware that the spectrum of illness due to MERS-CoV infection is not fully defined. Although most reported cases have had severe acute lower respiratory illness, mild infections, and infections with no apparent symptoms, have been reported. Additionally, in some cases, diarrhea preceded respiratory symptoms. Other early symptoms have included headache, chills, myalgia, nausea/vomiting, and diarrhea. Symptomatic contacts should be evaluated and, depending on their clinical history and presentation, considered for MERS-CoV testing. This includes rRT-PCR testing of lower/upper respiratory and serum specimens, and possibly MERS-CoV serology, if symptom onset was more than 14 days prior.

Close contacts³ who are ill and do not require hospitalization for medical reasons may, in consultation with the state or local health department, be cared for and isolated in their home while being evaluated for MERS-CoV infection. (Isolation is defined as the separation or restriction of activities of an ill person with a contagious disease from those who are well). The possible benefit of home quarantine or other measures, such as wearing masks, is uncertain due to lack of information about transmissibility from persons with mild, or no apparent, symptoms. Contacts with no apparent symptoms who test positive by PCR, especially in respiratory specimens or serum, likely pose a risk of transmission, although the magnitude and contributing factors are unknown. Providers should contact their state or local health department to discuss home isolation, home quarantine or other measures for close contacts, especially for patients who test positive, and to discuss criteria for discontinuing any such measures.

Recommendations may be modified as more data become available. For more information, see CDC’s Interim Home Care and Isolation or Quarantine Guidance for MERS-CoV.

CLOSE CONTACTS OF A PUI

Evaluation and management of close contacts³ of a PUI should be discussed with state and local health departments. Close contacts of a PUI should monitor themselves for fever and respiratory illness and seek medical attention if they become ill within 14 days after contact; healthcare providers should consider the possibility of MERS in these contacts.

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Clusters of Respiratory Illness in Which MERS-CoV Infection Should Be Considered

Clusters⁵ of patients with severe acute respiratory illness (e.g., fever and pneumonia requiring hospitalization) without recognized links to a case of MERS-CoV infection or to travelers from countries in or near the Arabian Peninsula² should be evaluated for common respiratory pathogens.⁴ If the illnesses remain unexplained, providers should consider testing for MERS-CoV, in consultation with state and local health departments.

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Laboratory Testing

To date, limited information is available on the pathogenic potential and transmission dynamics of MERS-CoV. To increase the likelihood of detecting MERS-CoV infection, CDC recommends collecting multiple specimens from different sites at different times after symptom onset. For more information, see CDC’s Interim Guidelines for Collecting, Handling, and Testing Clinical Specimens from PUIs for MERS-CoV. For a PUI, CDC strongly recommends testing a lower respiratory specimen (e.g., sputum, broncheoalveolar lavage fluid, or tracheal aspirate), a nasopharygeal/oropharygeal (NP/OP) swab, and serum, via the CDC MERS-CoV rRT-PCR assay. Lower respiratory specimens are preferred, but collecting nasopharyngeal and oropharyngeal (NP/OP) specimens, and serum, are strongly recommended depending upon the length of time between symptom onset and specimen collection. If symptom onset was more than 14 days prior, CDC also strongly recommends additional testing of a serum specimen via the CDC MERS-CoV serologic assay.

Almost all state health department laboratories are approved for MERS-CoV testing using CDC’s MERS-CoV rRT-PCR assay. Contact your state health department to notify them of PUIs and to request MERS-CoV testing. If your state health department is unable to test, contact CDC’s EOC at 770-488-7100.

 

Infection Control

Appropriate infection-control measures should be used while managing patients, including specimen collection from PUIs and probable or confirmed MERS cases. For CDC guidance on MERS-CoV infection control in healthcare settings, see Interim Infection Prevention and Control Recommendations for Hospitalized Patients with MERS-CoV. For CDC interim guidance to prevent MERS-CoV from spreading in homes and communities in the U.S., see Interim Home Care and Isolation or Quarantine Guidance for MERS-CoV.

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Footnotes

1. Fever may not be present in some patients, such as those who are very young, elderly, immunosuppressed, or taking certain medications. Clinical judgement should be used to guide testing of patients in such situations.
2. Countries considered in the Arabian Peninsula and neighboring include: Bahrain; Iraq; Iran; Israel, the West Bank and Gaza; Jordan; Kuwait; Lebanon; Oman; Qatar; Saudi Arabia; Syria; the United Arab Emirates (UAE); and Yemen.
3. Close contact is defined as a) being within approximately 6 feet (2 meters), or within the room or care area, of a confirmed MERS case for a prolonged period of time (such as caring for, living with, visiting, or sharing a healthcare waiting area or room with, a confirmed MERS case) while not wearing recommended personal protective equipment or PPE (e.g., gowns, gloves, NIOSH-certified disposable N95 respirator, eye protection); or b) having direct contact with infectious secretions of a confirmed MERS case (e.g., being coughed on) while not wearing recommended personal protective equipment. See CDC’s Interim Infection Prevention and Control Recommendations for Hospitalized Patients with MERS. Data to inform the definition of close contact are limited; considerations when assessing close contact include the duration of exposure (e.g., longer exposure time likely increases exposure risk) and the clinical symptoms of the person with MERS (e.g., coughing likely increases exposure risk). Special consideration should be given to those exposed in healthcare settings. For detailed information regarding healthcare personnel (HCP) please review CDC Interim U.S. Guidance for Monitoring and Movement of Persons with Potential Middle East Respiratory Syndrome (MERS-CoV) Exposure. Transient interactions, such as walking by a person with MERS, are not thought to constitute an exposure; however, final determination should be made in consultation with public health authorities.
4. Examples of respiratory pathogens causing community-acquired pneumonia include influenza A and B, respiratory syncytial virus, Streptococcus pneumoniae, and Legionella pneumophila.
5. In accordance with the World Health Organization’s guidance for MERS-CoV, a cluster is defined as two or more persons with onset of symptoms within the same 14 days period, and who are associated with a specific setting such as a classroom, workplace, household, extended family, hospital, other residential institution, military barracks, or recreational camp. See WHO’s Interim Surveillance Recommendations for Human Infection with Middle East Respiratory Syndrome Coronavirus [5 pages].

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