VIRUS - HIDDEN ENEMY
WHAT IS A VIRUS?
➤ A virus is not a living being
➤ It is defined as biological object because:
No cellular constitution
It shows a living behavior only if it
parasites a host cell - outside the host all viruses are similar to inorganic
matter: they can even crystallize
WHAT IS A VIRUS?
“Viruses are teeny-tiny infectious blobs” that are made up of either DNA or RNA wrapped up inside a protein coat. They are too small to be seen by a typical light microscope.
JUST TO HAVE AN IDEA OF VIRUS REAL SIZE
HUMAN VIRUSES
OVERVIEW ON VIRUS COMPONENTS
➤ In every virus we can find basic structures:
Just ONE Nucleic acid so that we can distinguish DNA viruses OR RNA viruses
A CAPSID made of proteins
Often there is also an ENVELOPE made of lipids plus proteins - sometimes it is very complex
EACH SPECIES HAS ITS OWN VIRUSES
SPILLOVER
Viruses can jump from a species to another one For example COVID-19 from bats to humans
VIRAL LIFE CYCLE
Lytic cycle Lysogenic cycle
WHY ARE ANTIBIOTICS NOT USEFUL TO FIGHT AGAINST VIRUSES?
How do antibiotics work against bacteria?
Antibiotics fight bacterial infections either by killing
bacteria or slowing and suspending its growth. They do
this by:
•
attacking the wall or coating surrounding bacteria
•
interfering with bacteria reproduction
WHAT CAN WE DO AGAINST VIRUS INFECTIONS?
➤
Viral infection are usually overcome by our immune system, if
we are young and healthy
➤
Prevention
➤
Vaccines (if available)
➤
