The CDC has updated its guidance for MERS, but the essential concept remains in place: Throw everything but the kitchen sink at it.

CDC guidance continues to recommend the full gamut of standard, contact, and airborne precautions, with healthcare workers wearing N95 respirators or powered air purifying respirators (PAPRs).1

“The guidelines also emphasize additional elements of infection control and prevention programs that should be in place to prevent transmission of any infection — including respiratory pathogens like MERS — in a healthcare setting,” David Kumar, MD, an epidemiologist in the CDC’s Division of Healthcare Quality Promotion said at a recent clinical briefing.

The guidelines emphasize early identification and prompt isolation of patients and extreme diligence when donning and doffing personal protective equipment.

“HCWs should be provided job- and task-specific education and training in preventing transmission of infectious agents,” Kumar said. “They should be medically cleared and tested and trained [to use] respiratory protection devices. They should be educated, trained, and practiced in the use of PPE prior to caring for a patient, including preventing contamination of clothing, skin, and the environment during the process of removing equipment.”

In addition to case identification and rapid isolation of patients, the CDC is warning of spread from visitors.

“Visitors should be restricted from entering a MERS patient’s room, but exceptions could be considered for those essential to the patient’s emotional well-being,” he said. “Visits should be scheduled and controlled. [Recommendations include] logging all visitors, screening all visitors for acute respiratory illness before entering the hospital, and evaluating the risk for the visitor, providing instructions on hand hygiene, limiting touching of surfaces, use of PPE and limiting their moments in other parts of the facility.”

“As with some other pathogens, there is no definitive point to discontinue isolation of a MERS patient. Duration of precaution will have to be determined on a case-by-case basis,” Kumar says.

The reasons for the full gamut of precautions include the following, the CDC reported:

• Current lack of a safe and effective vaccine and chemoprophylaxis,

• a possible high rate of morbidity and mortality among infected patients, and

• incompletely defined modes of transmission of MERS.

New PUI definitions

Given the outbreak in Korea, the CDC has revised its definitions of a person under investigation (PUI) for MERS. The revised PUI criteria include the following:

Fever and pneumonia or acute respiratory distress syndrome (based on clinical or radiologic evidence) and one of the following:

• A history of travel from countries in or near the Arabian Peninsula within 14 days before symptom onset, OR close contact 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 Peninsula, OR

• A history of being in a healthcare facility (as a patient, worker, or visitor) in the Republic of Korea within 14 days before symptom onset, OR

• A member of a cluster of patients with severe acute respiratory illness (e.g., fever and pneumonia requiring hospitalization) of unknown etiology in which MERS is being evaluated, in consultation with state and local health departments in the US.2

PUIs may extend out to people with fever and respiratory symptoms (e.g., cough, shortness of breath) that do not necessarily have pneumonia depending on travel and contact history. In addition, the CDC recommends the following measures for incoming, symptomatic patients:

• Take steps to ensure all persons with symptoms of a respiratory infection adhere to respiratory hygiene and cough etiquette, hand hygiene, and triage procedures throughout the duration of the visit.

• Consider posting visual alerts (e.g., signs, posters) at the entrance and in strategic places (e.g., waiting areas, elevators, cafeterias) to provide patients and HCP with instructions (in appropriate languages) about hand hygiene, respiratory hygiene, and cough etiquette. Instructions should include how to use face masks or tissues to cover nose and mouth when coughing or sneezing, to dispose of tissues and contaminated items in waste receptacles, and how and when to perform hand hygiene.

• Provide space and encourage persons with symptoms of respiratory infections to sit as far away from others as possible. If available, facilities may wish to place these patients in a separate area while waiting for care.

• Ensure rapid triage and isolation of patients who might have MERS infection.

• Identify patients at risk for having MERS infection before or immediately upon arrival to the hospital.

• Implement triage procedures to detect patients at risk for having MERS infections during or before patient triage or registration (e.g., at the time of patient check-in) and ensure that all patients are asked about the presence of symptoms of a respiratory infection and history of travel to areas experiencing transmission of MERS or contact with possible MERS patients.

• Immediately isolate those identified as at risk for having MERS infection.

• Implement Respiratory Hygiene and Cough Etiquette (i.e., placing a face mask over the patient’s nose and mouth) and isolate those at risk for MERS infection in an Airborne Infection Isolation Room.

• Provide supplies to perform hand hygiene to all patients upon arrival to facility (e.g., at entrances of facility, waiting rooms, at patient check-in) and throughout the entire duration of the visit to the healthcare setting.

Exposed workers

Monitoring and management of exposed personnel continues to be emphasized. “Personnel who care for MERS patients should be monitored and immediately report signs or symptoms of acute illness to their supervisor or a person designated by the facility for 14 days from their last known contact with the patient,” Kumar says.

Personnel who develop respiratory symptoms after an unprotected exposure, such as not wearing personal protective equipment at the time of contact, should either not report to work or stop working immediately, notify the designated person, seek medical attention, and comply with work restrictions until no longer infectious, he emphasized.

“Asymptomatic healthcare workers who have unprotected exposures to MERS patients should be excluded from work for 14 days from the last contact and monitored for signs and symptoms,” he says.


1. CDC Interim Infection Prevention and Control Recommendations for Hospitalized Patients with Middle East Respiratory Syndrome Coronavirus (MERS-CoV)UPDATED June 2015:

2. CDC. Updated Information and Guidelines for Evaluation of Patients for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Infection. June 11, 2015: