MERS (Middle East Respiratory Syndrome) (cont.)

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What causes MERS? How is MERS transmitted?

MERS is caused by a virus referred to as "MERS-CoV" from the coronavirus genus; MERS-CoV means Middle East respiratory syndrome coronavirus. The genus coronavirus includes viruses that infect animals, cause the common cold in humans, and caused the 2003 SARS outbreak in China. However, the MERS-CoV virus is different than other coronaviruses, including SARS-CoV, and had never been identified before 2012. MERS-CoV has been detected in camels in several countries but not in other livestock. It has been detected in camel meat, organs, milk and urine; infected camels may not be observably ill.

MERS-CoV is spread from person to person through respiratory droplet secretions. MERS has often infected people caring for a sick (MERS-CoV-infected) individual. Contact with infected body fluids, respiratory secretions, raw or undercooked meat, and unpasteurized dairy products of camels may be other sources of transmission to humans.

MERS-CoV infection should be suspected in travelers who've recently returned from the Arabian Peninsula or neighboring countries with a compatible illness occurring within 10 days of traveling.

Health-care workers or contacts of a MERS-infected individual are at risk, as are veterinary, farm, dairy, market, race track, and abattoir workers who handle camels.

What are risk factors for MERS-CoV infection?

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MERS-CoV can infect a person regardless of his/her health status or age group. Recent travelers returning from the Arabian Peninsula and neighboring countries who develop severe acute respiratory infection should be tested for MERS-CoV. Elderly people and those with underlying medical conditions such as diabetes, heart disease, or liver disease are at risk of severe infection. Close association with any person infected with MERS-CoV, as in caregivers, health-care workers, or household contacts, is a major risk factor. Contact with camel body fluids, respiratory secretions, raw or undercooked meat, and unpasteurized dairy products likely also poses a major risk of transmission to humans in the Arabian Peninsula and surrounding countries. Thus, those who work in these areas and handle live camels, or camel's meat or milk are at risk, including veterinarians and those who work at markets or race tracks, and those who slaughter, butcher, milk, and cook raw camel products. Cooked meat and pasteurized milk is safe to handle and consume. Not all camels may transmit the disease; Bactrian (Mongolian) camel herds currently show no infections with MERS, but researchers are not sure these camels have ever been exposed to the virus.

What are MERS symptoms and signs?

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Initially, the illness resembles influenza with fever and a mild cough. The breathing disorder often progresses to severe shortness of breath (dyspnea) and inability to maintain oxygenation (hypoxia). Progression may be rapid, or it may take several days. Severely affected people develop a potentially fatal form of respiratory failure, known as adult respiratory distress syndrome (ARD or ARDS). In addition to attacking the alveoli in the lungs, the virus also infects other organs in the body, causing kidney failure, inflammation of the heart sac (pericarditis), or severe systemic bleeding from disruption of the clotting system (disseminated intravascular coagulation). People with compromised immune systems such as severe rheumatoid arthritis or organ transplantation may not experience respiratory symptoms but can have fever or diarrhea.

Medically Reviewed by a Doctor on 4/13/2015

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MERS - Symptoms Question: What symptoms did you experience with your MERS infection?
MERS - Risk Factors Question: Did you have any MERS risk factors prior to infection?