Understanding Middle East Respiratory Syndrome (MERS)

Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: November 2026

Quick Answer

Middle East respiratory syndrome (MERS) is a severe respiratory infection caused by the MERS-CoV coronavirus [1]. It typically causes fever, cough and shortness of breath and can progress to pneumonia or kidney failure [1]. It spreads through close contact with infected people or camels and raw camel products [1]. There is no specific cure, so treatment is supportive care [1].

What the research says

• About 4 in 10 confirmed MERS patients died, and most hospitalized patients needed intensive care. In a systematic review and meta-analysis of 25 studies, the pooled case fatality risk was 39.1% (range 14.5%–100% across studies), with pooled risks of 78.2% for ICU admission and 73.0% for mechanical ventilation. Risks were highest in studies focused on ICU patients, so they reflect severe hospitalized cases (PubMed: Matsuyama et al., BMC Public Health, 2016 [2]).

• Older age, male sex, and chronic conditions predicted death. The same review identified older age, male sex, diabetes mellitus, renal disease, respiratory disease, heart disease, and hypertension as clinical predictors of MERS-associated death, and found that differences in study design explained much of the variation between studies (PubMed: Matsuyama et al., BMC Public Health, 2016 [2]).

• No antiviral treatment has clearly beaten supportive care. In a meta-analysis of MERS treatment studies, case fatality was as high as 71% in patients given ribavirin plus interferon and exactly the same in patients who received supportive treatment only. Chronic renal disease, diabetes, and hypertension raised the risk of death (P < .05), and the authors call for large prospective randomized studies (PubMed: Morra et al., Rev Med Virol, 2018 [3]).

What Is Middle East Respiratory Syndrome (MERS)?

Middle East Respiratory Syndrome (MERS) is a severe respiratory illness caused by a specific coronavirus known as MERS-CoV [1]. This virus is part of the same family that causes the common cold and COVID-19 [1]. MERS is notable for its severity, often leading to life-threatening complications such as pneumonia and multi-organ failure.

While cases have been reported globally, the vast majority of MERS infections have occurred within the Arabian Peninsula, particularly in Saudi Arabia [1]. The illness can spread between humans in close-contact settings, such as households and hospitals, and is also zoonotic, meaning it can jump from animals—specifically camels—to humans [1].

Key fact	Detail
What it is	A severe viral respiratory illness
Cause	MERS-CoV, a coronavirus in the same family as the viruses behind the common cold and COVID-19
Where most cases occur	The Arabian Peninsula, particularly Saudi Arabia
How it spreads	Close contact with infected people; contact with camels; raw camel meat or unpasteurized camel milk
Is there a cure?	No specific antiviral treatment; care is supportive
Mortality	Approximately 1 in 3 infected people

What are the symptoms of MERS, and how does it progress?

The symptoms of MERS can range from mild respiratory issues to severe systemic failure. The illness often progresses rapidly, requiring hospitalization for many patients. High fever is one of the most common early signs.

Symptom category	Common indicators
Primary respiratory	Persistent cough and dyspnea (significant shortness of breath)
Febrile response	High fever and chills
Digestive	Nausea, vomiting, and diarrhea
Serious complications	Pneumonia, respiratory failure, kidney failure, and multi-organ failure

Figure 1: MERS symptoms and disease progression, from fever, cough, and shortness of breath to pneumonia and kidney failure.

How does MERS spread, and who is at risk?

MERS-CoV is transmitted through contact with infected respiratory fluids, such as mucus or saliva [1].

How MERS Spreads

Route	What it involves
Human-to-human	Close contact with an infected person, most commonly in healthcare facilities or among family members living in the same home
Animal-to-human	Close contact with camels, such as grooming
Raw camel products	Consuming raw camel meat or unpasteurized camel milk

Who Is at Risk?

Individuals at the highest risk include those living in or traveling to the Arabian Peninsula, healthcare workers treating MERS patients, and those with direct contact with camels [1]. Furthermore, the risk of severe illness increases significantly for people with underlying health conditions, such as:

• Diabetes and cardiovascular disease [1]

• Chronic kidney, lung, or heart disease [1]

• Cancer or a compromised immune system [1]

Figure 2: MERS transmission pathways and the groups at highest risk.

How Is MERS Diagnosed?

Healthcare providers suspect MERS in patients who exhibit severe respiratory symptoms and have a history of travel to affected regions. Because MERS-CoV requires specialized testing, samples are often sent to dedicated laboratories [1].

Test	What it checks
Sputum and nasopharyngeal swabs	Detect the virus in the respiratory tract
Bronchoscopy	A procedure to look inside the lungs and collect fluid samples
Blood tests	Check for systemic infection and organ function

How is MERS treated and managed?

Currently, there is no specific antiviral treatment or cure that eliminates MERS-CoV from the body [1]. Instead, medical care focuses on supportive therapies to help the body fight the infection and manage severe complications.

Supportive care	Purpose
Supplemental oxygen	Assists with breathing difficulties
Mechanical ventilation	For patients experiencing respiratory failure
IV fluids	Maintain hydration and support organ function

How can you prevent MERS?

Preventing MERS involves a combination of personal hygiene and avoiding known environmental risks.

General Precautions

• Hand hygiene: Frequent washing with soap and water [1]

• Respiratory etiquette: Covering the nose and mouth when coughing or sneezing [1]

• Surface safety: Regular cleaning and disinfecting of frequently touched surfaces [1]

• Animal safety: Washing hands after touching camels and avoiding raw or unpasteurized camel products [1]

Caregiver Guidelines

Those caring for MERS patients must use Personal Protective Equipment (PPE), including face masks, gowns, and gloves [1]. Additionally, all laundry and dishes used by the infected person should be handled with gloves and washed thoroughly [1].

Figure 3: Key MERS safety measures — hand washing, covering coughs and sneezes, avoiding contact with sick people or animals, and PPE for caregivers.

What is the outlook and mortality rate for MERS?

MERS is a highly lethal condition, with a mortality rate of approximately 1 in 3 infected individuals [1]. However, experts note that the actual mortality rate might be lower if there are many mild, undiagnosed cases that are not captured in official statistics [1].

Patients who develop severe symptoms often require intensive hospital care to recover fully.

Key Takeaways

MERS remains a significant public health concern, particularly for those traveling to or living in the Arabian Peninsula. While the mortality rate is high, the risk can be significantly mitigated through strict adherence to hygiene protocols and avoiding high-risk contact with camels. Staying informed about travel advisories and seeking immediate medical attention for severe respiratory symptoms is crucial for safety.

Take the Next Step

If you are planning to travel to the Middle East, consult your healthcare provider regarding the latest public health recommendations. If you develop a fever or cough after traveling, seek medical attention immediately and inform your provider of your travel history.

Frequently Asked Questions

1. What is MERS?

Middle East Respiratory Syndrome (MERS) is a severe respiratory illness caused by a coronavirus called MERS-CoV.

2. How do people get MERS?

MERS spreads through close contact with infected people, contact with camels, or by consuming raw camel meat or milk.

3. What are the main symptoms of MERS?

The most common symptoms are fever, cough, and shortness of breath. Some people also experience diarrhea and vomiting.

4. Where is MERS most common?

Most cases have occurred in the Arabian Peninsula, specifically in Saudi Arabia and its surrounding countries.

5. Is there a cure for MERS?

There is no specific cure or antiviral treatment for MERS; doctors provide supportive care to help the body fight the virus.

6. How lethal is MERS?

Approximately 1 in 3 people who are diagnosed with MERS die from the infection.

7. Can MERS be prevented?

Yes, by washing hands frequently, avoiding contact with sick people or camels, and not consuming raw camel products.

8. Who is at risk for severe MERS?

People with chronic conditions like diabetes, cancer, or heart, lung, and kidney disease are at a higher risk for severe illness.

9. Should I see a doctor if I have symptoms?

Yes, especially if you have recently traveled to the Middle East or been in contact with someone who has MERS.

10. Is MERS the same as COVID-19?

Both are caused by coronaviruses, but they are different viruses. MERS-CoV is generally more lethal but less transmissible than the virus that causes COVID-19.

References

1. Cleveland Clinic. Middle East Respiratory Syndrome (MERS). Cleveland Clinic. June 30, 2025. https://my.clevelandclinic.org/health/diseases/22633-middle-east-respiratory-syndrome-mers

2. Matsuyama R, Nishiura H, Kutsuna S, Hayakawa K, Ohmagari N. Clinical determinants of the severity of Middle East respiratory syndrome (MERS): a systematic review and meta-analysis. BMC Public Health. 2016;16(1):1203. doi:10.1186/s12889-016-3881-4. PMID: 27899100.

3. Morra ME, Van Thanh L, Kamel MG, et al. Clinical outcomes of current medical approaches for Middle East respiratory syndrome: a systematic review and meta-analysis. Rev Med Virol. 2018;28(3):e1977. doi:10.1002/rmv.1977. PMID: 29664167.

Medical Disclaimer

This article is for informational purposes only and does not constitute medical advice. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read here.