Middle East Respiratory Syndrome Coronavirus
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a novel beta coronavirus that was first reported to cause human infection in a man in Saudi Arabia in September 2012. Fatality rate is almost 50%. All diagnosed cases were among people who resided in or traveled from four countries including the Kingdom of Saudi Arabia, United Arab Emirates, Qatar, or Jordan. People in France, United Kingdom, Italy and Tunisia have become infected after traveling to these countries or having person-to-person contact with travelers from these countries. To date, no cases have been reported in the United States. Incubation periods for MERS CoV may be longer than 10 days.
CDC has updated its criteria for who should be evaluated for MERS-CoV. In the previous guidance (HAN 348, June 7, 2013), CDC did not recommend MERS-CoV testing for people whose illness could be explained by another etiology. The new guidance, available at http://www.cdc.gov/coronavirus/mers/interim-guidance.html, states that testing for MERS-CoV and other respiratory pathogens can be done simultaneously and that positive results for another respiratory pathogen should not necessarily preclude testing for MERS-CoV.
Persons who develop severe acute lower respiratory illness within 14 days after traveling from the Arabian Peninsula or neighboring countries should be evaluated according to current guidelines.
- A person with an acute respiratory infection, which may include fever (? 38°C , 100.4°F) and cough; AND
- suspicion of pulmonary parenchymal disease (e.g., pneumonia or acute respiratory distress syndrome based on clinical or radiological evidence of consolidation); AND
- history of travel from the Arabian Peninsula or neighboring countries* within 14 days; In addition, the following persons may be considered for evaluation for novel coronavirus infection:
- Persons who develop severe acute lower respiratory illness of known etiology within 14 days after traveling from the Arabian Peninsula or neighboring countries but who do not respond to appropriate therapy; OR
- Persons who develop severe acute lower respiratory illness who are close contacts of a symptomatic traveler who developed fever and acute respiratory illness within 14 days of traveling from the Arabian Peninsula or neighboring countries.
Persons who meet these criteria should be reported to state and local health departments. There is no specific treatment for MERS-CoV infection; care is supportive.
Diagnosis relies on testing with specific real time reverse transcription polymerase chain reaction (RT-PCR). The Food and Drug Administration (FDA) issued an Emergency Use Authorization on June 5, 2013, to authorize the use of the CDC Novel Coronavirus 2012 Real-time RT-PCR Assay (NCV-2-12 rRT-PCR Assay) to test for MERS-CoV in clinical respiratory, blood and stool samples. This assay is being deployed to Laboratory Response Network (LRN) laboratories in all 50 states.
To increase the likelihood of detecting MERS-CoV, CDC recommends collection of specimens from different sites including a nasopharyngeal swab and a lower respiratory tract specimen such as sputum, bronchoalveolar lavage, bronchial wash, or tracheal aspirate. Lower respiratory specimens are preferred, but collecting nasopharyngeal and oropharyngeal (NP/OP) specimens, as well as stool and serum, are strongly recommended. If possible, specimens should be collected at different times after symptom onset. For more information, see CDC’s Interim Guidelines for Collecting, Handling, and Testing Clinical Specimens at http://www.cdc.gov/coronavirus/mers/guidelines-clinical-specimens.html. Many state health department laboratories are approved for MERS-CoV testing using the CDC rRT-PCR assay.
Genetic sequence analyses have shown that this new virus is different from other known human coronaviruses, including the one that caused severe acute respiratory syndrome (SARS). Additional information is available at the CDC MERS website at: http://www.cdc.gov/coronavirus/mers/index.html
