Middle East respiratory syndrome: SARS redux?
ABSTRACTMiddle East respiratory syndrome (MERS) is caused by the Middle East respiratory syndrome coronavirus (MERS-CoV). Although predominantly affecting countries across the Arabian Peninsula, the infection has been exported by travelers to countries around the world, including the United States. The virus has caused several healthcare-related outbreaks, so prompt recognition and patient isolation are critical to containing the spread of infection. Healthcare providers are urged to stay current on the evolving outbreak, and to screen at-risk travelers for possible MERS.
KEY POINTS
- In MERS, initial complaints are of fever, cough, chills and myalgia. In a subset of patients, usually those with underlying illnesses, the disease can progress to fulminant sepsis with respiratory and renal failure and death.
- Healthcare providers should regularly visit the US Centers for Disease Control and Prevention website for current information on countries experiencing a MERS outbreak, and for advice on how to identify a potentially infected patient.
- MERS-CoV has caused several healthcare-related outbreaks, so prompt identification and isolation of infected patients is critical to limiting the spread of infection. A “patient under identification” (ie, a person who has both clinical features and an epidemiologic risk) should be cared for under standard, contact, and airborne precautions.
TREATMENT
Unfortunately, treatment for MERS is primarily supportive.
Ribavirin and interferon alfa-2b demonstrated activity in an animal model, but the regimen was ineffective when given a median of 19 (range 10–22) days after admission in 5 critically ill patients who subsequently died.22 A retrospective analysis comparing 20 patients with severe MERS-CoV who received ribavirin and interferon alfa-2a with 24 patients who did not reported that while survival was improved at 14 days, the mortality rates were similar at 28 days.23
A systematic review of treatments used for severe acute respiratory syndrome (SARS) reported that most studies investigating steroid use were inconclusive and some showed possible harm, suggesting that systemic steroids should be avoided in coronavirus infections.24
PREVENTION
Healthcare-associated outbreaks of MERS are well described, and thus recognition of potential cases and prompt institution of appropriate infection control measures are critical.15,25
Healthcare providers should ask patients about recent travel history and ascertain if they meet the CDC criteria for a “patient under investigation” (PUI), ie, if they have both clinical features and an epidemiologic risk of MERS (Table 1). However, these recommendations for identification will assuredly change as the outbreak matures, and healthcare providers should refer to the CDC website for the most up-to-date information.
Once a PUI is identified, standard, contact, and airborne precautions are advised. These measures include performing hand hygiene and donning personal protective equipment, including gloves, gowns, eye protection, and respiratory protection (ie, a respirator) that is at least as protective as a fit-tested National Institute for Occupational Safety and Health-certified N95 filtering face-piece respirator. In addition, a patient with possible MERS should be placed in an airborne infection isolation room.
Traveler’s advice
The CDC does not currently recommend that Americans change their travel plans because of MERS. Clinicians performing pretravel evaluations should advise patients of current information on MERS. Patients at risk for MERS who develop a respiratory illness within 14 days of return should seek medical attention and inform healthcare providers of their travel history.
SUMMARY
Recent experience with SARS, Ebola virus disease, and now MERS-CoV highlights the impact of global air travel as a vector for the rapid worldwide dissemination of communicable diseases. Healthcare providers should elicit a travel history in all patients presenting with a febrile illness, as an infection acquired in one continent may not become manifest until the patient presents in another.
The scope of the current MERS-CoV outbreak is still evolving, with concerns that viral evolution could result in a SARS-like outbreak, as experienced almost a decade ago.
Healthcare providers are advised to screen patients at risk for MERS-CoV for respiratory symptoms, and to institute appropriate infection control measures. Through recognition and isolation, healthcare providers are at the front line in limiting the spread of this potentially lethal virus.
