Disease Description (Causes and Symptoms)
- Cause: Middle East Respiratory Syndrome Coronavirus (MERS-CoV), a novel betacoronavirus, is the cause. Bats are presumed to be the natural host, and camels have been reported as intermediate hosts.
- Pathophysiology: The virus invades respiratory epithelial cells, causing inflammation and lung damage, and enters via the DPP4 (CD26) receptor on human cells. In severe cases, it may progress from pneumonia to acute respiratory distress syndrome (ARDS), systemic inflammation, and multiorgan failure; kidney injury (acute renal failure) commonly accompanies the illness.
- Main symptoms: After an incubation period of 7–14 days, fever, cough, shortness of breath, and chest pain are common, and some patients develop gastrointestinal symptoms such as diarrhea and vomiting. In severe patients, the disease may progress to pneumonia, acute renal failure, and respiratory failure, and the case fatality rate is high (approximately 30–40%, depending on the report).
Treatment
- Standard treatment: As there are no specifically approved antiviral drugs or vaccines, treatment is mainly supportive (symptomatic).
- Mild cases: Symptom monitoring and symptomatic treatment (such as fever reduction and fluid replacement), with isolation and infection control.
- Severe cases: Intensive care treatment, including oxygen therapy, mechanical ventilation (if necessary), hemodynamic stabilization, and renal replacement therapy (dialysis) in cases of renal failure. ECMO may be considered if necessary.
- Attempted drug treatment (limited evidence): Antiviral and immunotherapy treatments, such as combination therapy with interferon and ribavirin, have been used in some cases, but they are not recommended as established standard treatment. Antibiotics are used when a secondary bacterial infection is suspected.
- Lifestyle management and precautions: Get sufficient rest and fluids, and visit a medical institution immediately if fever or respiratory symptoms worsen. Wear a mask, practice hand hygiene, and follow cough etiquette to reduce transmission to others. If infection is suspected, undergo isolation and testing according to public health guidelines.
- Risk of complications: Pneumonia, ARDS, acute renal failure, multiorgan failure, and secondary bacterial infection. Older adults and people with underlying conditions (such as cardiovascular disease, diabetes, chronic lung disease, and chronic kidney disease) have an increased risk of severe illness and death.
- Prognosis: It varies depending on age and underlying conditions, and the overall mortality rate is relatively high (approximately 30–40%, depending on the report). Even young patients can progress to severe illness.
Checkpoints Before an Outpatient Visit (Including Items to Bring and Sample Questions)
- Items to bring (helpful for consultation and testing):
- Medications currently being taken (prescriptions and medication list)
- Underlying conditions and past medical history (especially heart, lung, and kidney disease and immunosuppressed status)
- Recent travel history (including travel to the Middle East) and whether there has been contact with animals such as camels
- Date symptoms began and their progression (fever records, whether cough or shortness of breath has worsened, and whether diarrhea is present)
- Recent test results (if possible, sputum test, blood test, and imaging results, etc.)
- Information to tell medical staff first during an outpatient visit: Recent travel to the Middle East, contact with a hospital or patient (exposure at a medical institution), and whether there has been acute worsening (shortness of breath, cyanosis, or decreased consciousness).
- Sample questions (sentences the patient can prepare to ask medical staff):
- "I recently traveled to the Middle East (such as Saudi Arabia). Do I need to be tested?"
- "My kidney function is poor. If the disease worsens, how likely is it that I will need dialysis?"
- "When will isolation and a return to daily activities (return to work) be possible?"
Examples of General Questions to Ask the Doctor
- What are the main side effects and precautions for this medication (prescription medicine)?
- Given my condition, how likely is it that I will need intensive care or ventilator treatment?
- How long should I self-isolate until my symptoms improve, and what precautions should I take around other people?
Examples of Disease-Specific Questions
- I have a history of travel to the Middle East (or contact with camels). I have a fever and cough; what tests should I undergo and when (including the type of specimen and timing of testing)?
- Someone in my family has an underlying condition (for example, chronic kidney failure or immunosuppression). What special infection-control measures should I follow when caring for them at home?
Additional Key Points
- Diagnosis: Confirmed by RT-PCR of respiratory specimens (sputum, bronchoalveolar lavage fluid, etc.); serologic testing may be used as an adjunct.
- Prevention: Practice hand hygiene and cough etiquette, avoid contact with people who have fever or respiratory symptoms, avoid contact with camels and consumption of raw camel milk products, and follow standard, droplet, contact, and airborne infection-control guidelines in medical institutions.
- If infection is suspected, follow the guidance of public health authorities and be sure to inform medical staff of your travel and exposure history.