Covid-19

About coronaviruses

What is a coronavirus?

Coronaviruses form a large family of viruses that can cause a range of illnesses. They include the common cold as well as more serious diseases such as SARS (severe acute respiratory syndrome), MERS (Middle East respiratory syndrome) and, more recently, COVID-19.

Coronaviruses have been around for many years so humans have built up a general immunity to them. This means when we get a common cold, it is usually not very severe.

However, coronaviruses are not just present in humans. Many animals develop coronavirus-related illnesses and sometimes those viruses can mutate and be passed on to humans. When this happens, the disease can be more severe because the human body has not had to fight the illness before. SARS, MERS and COVID-19 are examples of this happening in recent years.

When a new strain of coronavirus is discovered, it is called a ‘novel’ coronavirus.

Different types of coronavirus

SARS

Key facts Severe acute respiratory syndrome (SARS) is a viral illness that can cause severe ...

MERS

Key facts Middle East respiratory syndrome (MERS) is a rare disease. MERS is caused by ...

COVID-19

Managing COVID Preparing for infection What to do if you test positive Advice for close ...

Common cold

What are colds? A cold is a viral infection that affects the nose, the throat ...