The good viruses

Viruses are tiny microbes that are so basic that they are not even cells!  Viruses are just genetic material (genes) wrapped up inside a strong ‘coat’ made of protein.  They cannot survive by themselves, viruses have to use a host to grow and multiply which makes them a type of parasite.   

Some viruses are very clever.  They don’t die off if they don’t have a host, they just hibernate (they become dormant) and wait for the right conditions to come along so they can make copies of themselves.  Viruses can spread very easily from one person to the next just by touch or by sneezing or coughing when they fly out into the air in tiny water droplets.  If a person doesn’t cover their mouth and nose when they sneeze or cough, you could breathe in their virus!  Other viruses are spread when people are lazy about personal hygiene and they don’t wash their hands very often, especially when they have been to the toilet.  Viruses also wait in areas you wouldn’t expect them to like door-handles or telephones so you should make sure to clean up after you and that you wash your hands regularly!

There aren’t really many good viruses but a virus that did do some good was the vaccinia virus.  In 1796, Dr Edward Jenner found that milkmaids infected with cowpox, a mild disease, did not get smallpox, a more deadly disease that only affects humans.  Smallpox killed about 35% of people who were infected and left many people who survived with terrible scars on their skin.  However, people that were first infected with cowpox were immune to smallpox!  Dr Jenner invented the word ‘vaccination’ and his discovery led to the science of immunology.  His work saved a massive amount of lives and led, in 1980, to the World Healthy Organisation (WHO) to declare that ‘the worldand its peoples’ were free from common smallpox.  It is the only infectious disease in history to have been completely removed from nature by mankind!

Sometimes, being infected by a virus doesn’t mean you’ll get sick.  A lot of adults have a virus called CMV – the cytomegalovirus – a member of the herpes virus family.  You can get this at any time and it usually doesn’t make you very sick – sometimes it doesn’t make you sick at all.  The virus lives in your body very happily but in its dormant state (so it is inactive, like its sleeping).  It can still be very dangerous as it can wake up and cause problems if you are seriously ill or if your immune system is damaged.  It is really important to keep fit and healthy so you can fight viruses that may be in your body if they decide to wake up!   

Viruses have different shapes – they are most commonly seen as rods, spheres, or many-sided spheres.  There are even viruses shaped like a spaceship!  These are called bacteriophages and they infect and bacteria.  Researchers and scientist are trying to find ways of using these viruses to fight bacterial infections that can be used instead of antibiotics.

All in all, viruses are some of the cleverest microbes there are.  Your best bet is to make sure your personal hygiene is good, your environment is clean and tidy and that you stay fit and healthy so that if you do catch a virus, your body is ready to fight it!