Coronaviruses (Common Cold Viruses)

About This Disease

Coronaviruses usually cause mild respiratory tract infections like the common cold and are caused by four human coronaviruses. Two exceptions are SARS-CoV, which can cause Severe Acute Respiratory Syndrome, and MERS-CoV, which causes Middle East Respiratory Syndrome.

Signs and Symptoms

Common human coronaviruses cause mild upper-respiratory tract infections, such as the common cold, that last for a short amount of time. Symptoms include fever, sore throat, cough, and runny nose. These viruses can also cause lower-respiratory tract illnesses, such as pneumonia, in the elderly and immunocompromised.

Symptoms of SARS-CoV infections are influenza-like and include a high fever, headache, malaise, headache, and body aches. Some patients develop diarrhea, a dry cough, and shortness of breath. The majority of patients will develop pneumonia. Severe cases will often develop rapidly, progressing to respiratory distress and requiring intensive medical care.

Symptoms of MERS-CoV can range from no symptoms or mild cold-like symptoms to more severe acute respiratory illness with fever, cough, and shortness of breath. Some may develop gastrointestinal symptoms such as diarrhea, nausea, and vomiting. MERS causes severe complications such as pneumonia and kidney failure, with an estimated 30-40% mortality rate. Individuals with weakened immune systems or pre-existing medical conditions such as chronic lung disease are at a higher risk of being infected and developing severe illness.


Human coronaviruses spread from an infected person to others by respiratory droplets through the air by coughing and sneezing, through close personal contact, and by touching contaminated surfaces.

In addition to human-to-human transmission, SARS-CoV and MERS-CoV can also be spread through animal-to-human transmission. SARS-CoV can infect animals such as monkeys, cats, dogs, and rodents. MERS-CoV can infect animals such as camels.


Coronavirus infection can be diagnosed by your healthcare provider. Laboratory tests on blood or nose and throat swabs are used to confirm whether your illness is due to the common coronavirus. Testing is conducted at the State Laboratories Division only after approval through the Disease Investigation Branch.

Real-time reverse transcription polymerase chain reaction (RT-PCR) is used to test for SARS-CoV and MERS-CoV in clinical respiratory, blood, and stool samples. Serologic testing can be used to detect SARS-CoV antibodies produced after infection. Viral culture can also be used to detect the virus.


There are currently no specific treatments for illnesses that are caused by coronaviruses. Most people will recover from the illness on their own. Treatment for illnesses caused by human coronavirus infections are generally for symptom relief, such as fever-reducing medication.

Individuals with MERS or SARS often require medical care to help relieve symptoms. Severe cases require care to support vital organ functions.


Most people get infected with common coronaviruses more than once in their lifetime. Infection with one of the coronaviruses does not give immunity to the others or prevent future coronavirus infections.

Risk in Hawaii

The common coronaviruses typically circulate in Hawaii during the winter months.

Currently, there are no areas of the world reporting transmission of SARS. The majority of MERS cases are reported by Saudi Arabia and other countries in the Middle East. The risk of SARS and MERS to the general public in Hawaii and the rest of the United States remains low.


There are currently no vaccines against coronaviruses available.

You can reduce your risk of infection and protect others by washing your hands with soap and water, avoid touching your eyes, nose, and mouth, avoiding close contact with sick people, covering your mouth and nose when you sneeze and cough, and disinfecting objects and surfaces.

Additional Resources

Information for Clinicians

Healthcare providers should maintain awareness of the need to detect patients who should be evaluated for MERS-CoV and SARS-CoV. Please see Interim Guidance on the CDC website under Additional Resources.

If you are physician or healthcare provider and suspect MERS-CoV or SARS-CoV in one of your patients, please contact the Hawaii Department of Health.

MERS-CoV – Centers for Disease Control and Prevention (CDC)


Last Reviewed: September 2017