Sunday, 21 July 2013

What are Coronaviruses and How Do They Affect Us?

Coronaviruses have been in the news a lot lately. They have a frightening reputation and are responsible for some serious and even deadly diseases. SARS (Severe Acute  Respiratory Syndrome) is caused by a coronavirus. The current version of concern is the MERS (Middle East Respiratory Syndrome) coronavirus. As its name suggests, it was first noticed in the Middle East. The MERS virus sometimes causes a life-threatening infection and is in danger of spreading internationally. Not all members of the coronavirus family cause serious illness, however. Some produce diseases that are quite mild and don't even require medical treatment.

Structure of a Coronavirus
A Coronavirus
Photo Credit: Dr. Fred Murphy and the CDC
Public domain image
Like all viruses, a coronavirus consists of microscopic particles called virions. Each virion is made of a core of nucleic acid surrounded by a coat of protein. The protein coat of a coronavirus is covered by a lipid envelope.

The nucleic acid of the coronavirus virus is RNA, or ribonucleic acid. The RNA contains the genes of the virion. In other organisms and in many viruses, DNA (deoxyribonucleic acid) is the genetic material.

Coronaviruses get their name from the club-like projections or spikes on their surface. The spikes look somewhat like the rays of the sun's corona.

Diseases and Symptoms Caused by the Coronavirus

The coronavirus causes problems in the respiratory system. Despite its bad reputation, the virus usually causes only a mild or moderately severe disease. There are several varieties of the virus. Some types are very common, and most people have been infected by them during their lives. People may think that they simply have a cold when they are infected by one of these types, and they recover with no specific treatment. Symptoms of a coronavirus infection generally include a runny nose, a cough, a sore throat and a fever.

Occasionally, however, the press announces the discovery of a particular virulent and dangerous form of coronovirus, as has happened recently in the case of the MERS virus.

SARS (Severe Acute Respiratory Syndrome)

The SARS variety of the coronavirus appeared in 2003 and disappeared (apparently) in 2004. It caused a different set of symptoms from its relatives. An infected person first experienced a high fever. Other symptoms included a headache and body aches. The person often experienced diarrhea and respiratory problems as well, including a cough and pneumonia. WHO (the World Health Organization) reported that 8,098 people around the word were diagnosed with SARS. 774 of these people died.

MERS (Middle East 
Respiratory Syndrome)

The MERS virus was discovered in 2012. Most people who have become infected by the virus have experienced severe respiratory problems, and about half of the people who have become infected have died. Some people have experienced mild symptoms from a MERS infection, however. The virus is spread by close contact between an infected person and someone else.

According to the Public Health Agency of Canada, as of July 21st, 2013, the MERS virus has appeared in eight countries: Saudi Arabia, Jordan, Qatar, the United Arab Emirates, the United Kingdom, France, Italy and Tunisia. At the moment there have been no incidences of the disease in North America. Health agencies are monitoring the situation closely, though. Officials say that there is no need to panic but that normal steps to prevent viral infections should be followed.

Protecting Yourself From Viral Infections

There are some precautions that you can take to reduce the chance of becoming infected by a virus and to protect others from becoming infected. Recommendations include:
  • Wash your hands often and thoroughly for at least twenty seconds each time.
  • Use a hand sanitizer that contains alcohol if soap and water aren't available.
  • Don't touch your nose, mouth or eyes with unwashed hands.
  • Avoid close contact with people who are obviously sick.
  • Stay at home if you are sick yourself to protect others. 
  • Cover your nose and mouth when you sneeze.
  • Disinfect surfaces that are frequently touched, such as door knobs.