Interim Guidance for Healthcare Professionals

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 is limited and continues to evolve.

Limited data on the clinical presentation of MERS are available; most published clinical information to date is from critically ill patients. 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 Patient Under Investigation (PUI):

  1. Fever1 AND pneumonia or acute respiratory distress syndrome (based on clinical or radiologic evidence) AND EITHER:
    • history of travel from countries in or near the Arabian Peninsula2 within 14 days before symptom onset, OR
    • close contact3 with a symptomatic traveler who developed fever and acute respiratory illness (not necessarily pneumonia) within 14 days after traveling from countries in or near the Arabian Peninsula2, OR
    • a member of a cluster of patients with severe acute respiratory illness (e.g., fever1 and pneumonia requiring hospitalization) of unknown etiology in which MERS-CoV is being evaluated, in consultation with state and local health departments,


  2. Fever1 AND symptoms of respiratory illness (not necessarily pneumonia; e.g., cough, shortness of breath) AND being in a healthcare facility (as a patient, worker, or visitor) within 14 days before symptom onset in a country or territory in or near the Arabian Peninsula2 in which recent healthcare-associated cases of MERS have been identified.
  3. Fever1 OR symptoms of respiratory illness (not necessarily pneumonia; e.g. cough, shortness of breath) AND close contact3 with a confirmed MERS case while the case was ill.

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).

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Evaluation and Management of Close Contacts


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 incompletely 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 more extensive MERS-CoV testing, including 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.


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.


Reporting Patients 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.
  • 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.

Please contact the CDC MERS Team if you have any questions:

There are two options to submit a completed MERS PUI short form to CDC:

  1. Online
    Health departments can fill out the PUI short form online which automatically enters it into a secure database and submits the information to CDC. To begin completing PUI short forms online, state health departments should contact the CDC MERS Team at to obtain a unique state-specific password. Once you have a password, click the online PUI short form link below, select your state from the drop-down box, enter your unique state-specific password obtained from CDC, and click “Login.” Within the form, enter a unique State ID for the PUI and click “Load / Check STATE ID” to begin entering the information. Click “Save” when completed. In the near future, health departments will have access to their state-specific PUI short form information, including previously submitted short forms.
  2. By FAX or email
    Alternatively, health departments may download, print, and send the completed investigation short form below by FAX to CDC at 770-488-7107 or attach the short form to an email to (subject line: MERS Patient Form).

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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. 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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  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 Cdc-pdf[5 pages]External.

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