Managing MERS Cases and Contacts

Confirmed case: Definition, reporting, and next steps

A positive case is a person who has laboratory confirmation of MERS-CoV infection. Confirmatory laboratory testing requires a positive MERS real-time reverse transcription polymerase chain reaction (rRT-PCR) test at CDC. A positive MERS test performed at a laboratory within the laboratory response network (LRN) is considered a presumptive positive until it can be confirmed by CDC diagnostic testing.

In accordance with the Emergency Use Authorization (EUA) instructions for use of the U.S. MERS-CoV rRT-PCR, any specimen with a MERS-CoV presumptive positive interpretation identified at a laboratory within the LRN, should be shipped to CDC in accordance with the CDC-10488 test order for confirmatory testing. If an LRN laboratory has a presumptive positive test result without a residual specimen available, and a new specimen cannot be collected, please contact the CDC Emergency Operations Center.

State or local health departments should immediately contact CDC to discuss further epidemiologic investigation and management of an equivocal or presumptive positive test result, a confirmed case, or both.

State or local health departments should coordinate isolation for people with confirmed MERS and home quarantine for their contacts, respectively. CDC will work with health departments to determine these procedures.

Reporting MERS Persons Under Investigation (PUIs)

• All PUIs for MERS who are awaiting testing or test results should remain quarantined and avoid contact with others, if possible. Any positive MERS patient should be isolated and avoid contact with others. Hospitalized patients who are PUIs or presumptive positive MERS patients should follow all recommended MERS-CoV infection controls until testing results are negative.
• State and local health departments must submit all MERS-CoV rRT-PCR results (e.g., negative, positive, equivocal) via the LRN, in accordance with the EUA instructions for use.
• Any PUI for MERS with equivocal or presumptive positive MERS test results must be immediately reported to CDC with residual specimen sent to CDC for confirmatory testing.
• CDC staff are available for epidemiologic and laboratory consultation for MERS. Contact the CDC Emergency Operations Center.

Several state or local public health labs offer MERS testing. Clinicians should first contact their local or state health departments to discuss MERS PUIs and testing.

Evaluation and management of close contacts

Close contacts of a confirmed case

As part of investigation of confirmed cases, close contacts^[A] of a confirmed case should be actively monitored by health departments, or monitor themselves, for fever Aor symptoms of respiratory illness for 14 days after the close contact. State and local public health departments should strongly consider quarantining contacts during active monitoring periods. A person who develops fever ^[B]or symptoms of respiratory illness within 14 days following close contact^[A] with a confirmed case of MERS should be tested 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 and testing in consultation with state and local health departments and CDC.

Clinicians and public health professionals should be aware that a wide spectrum of illness in patients with MERS has been reported, ranging from asymptomatic to severe acute respiratory illness resulting in death. Symptomatic contacts should be tested. This includes testing of upper and (if possible) lower respiratory specimens for MERS-CoV by rRT-PCR. If the patient's symptom onset was more than 14 days prior to testing, the situation should be discussed further with state and local health departments and CDC.

People who are confirmed to have MERS and who do not require hospitalization for medical reasons may isolate at home; this decision should be made by the state or local health department based on individual circumstances and in conjunction with CDC. Close contacts who are symptomatic and awaiting MERS testing or MERS testing results, and who do not require hospitalization for medical reasons, should be quarantined. Quarantine at home may be considered; this decision should be made by the state or local health department and in conjunction with CDC. Providers should contact their state or local health department to discuss home isolation or home quarantine for people with confirmed MERS or their contacts, respectively.

All contacts should be monitored for 14 days after last exposure. Contacts with no apparent symptoms who test positive for MERS by rRT-PCR in respiratory specimens likely pose a risk of transmission, although the magnitude and contributing factors are unclear.

Close contacts of a PUI

Evaluation and management of close contacts 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.

Clusters of respiratory illness in which MERS should be considered

Clusters of patients with severe acute respiratory illness without recognized links to a case of MERS-CoV infection or to travelers from countries in or near the Arabian PeninsulaB should be tested for common respiratory pathogens. If the illnesses remain unexplained, providers should consider testing for MERS, in consultation with state and local health departments and CDC.