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For many years’ researchers have cultivated animal viruses by inoculating suitable
host animals or embryonated eggs—fertilized chicken eggs incubated about 6 to 8
days after laying. For example, the myxoma virus grows well on the chorioallantoic
membrane, whereas the mumps virus prefers the allantois cavity. The infection may
produce a local tissue lesion known as a pock, whose appearance often is
characteristic of the virus. More recently animal viruses have been grown in tissue
(cell) culture on monolayers of animal cells. This technique is made possible by the
development of growth media for animal cells and by the advent of antibiotics that can
prevent bacterial and fungal contamination. Animal viruses, in particular, can cause
microscopic or macroscopic degenerative changes or abnormalities in host cells and in
tissues called cytopathic effects. Cytopathic effects may be lethal. You may not always
get sick from viral infections. Your immune system may be able to fight it off.

For most viral infections, treatments can only help with symptoms while you wait for
your immune system to fight off the virus. Antibiotics do not work for viral infections.
There are antiviral medicines to treat some viral infections. Vaccines can help prevent
you from getting many viral diseases. In spite of well-equipped laboratories and health
care centers why is treatment of viral infections becoming a daunting task? Viruses
mutate very quickly. Made up of ribonucleic acid (RNA), as this genetic material exists
on a single strand, unlike a double-stranded DNA, it easily gets cut up and remixed
once broken. This enables viruses to mutate quickly, meaning that any cures or
vaccines made for a specific RNA may quickly become obsolete. All
vaccines work by convincing the body’s immune system to mount
a response to a foreign invader, whether it’s a virus, bacterium,
or parasite. Classic methods involve taking a whole virus,
weakening or killing it, then injecting its remains into a person’s
body. This way of vaccine production becomes useless when
viruses undergo mutation and change their antigenic
structures. More than this, vaccines generally take many years to
reach the market as they must go through six developmental
steps including a three-phase clinical development stage. This
means that, by the time an effective vaccine has been developed and approved as
safe-to-use, the emergency may have blown over. ‘Discretion is better part of valour’. It
is always safe to remain calm and composed till more experiments and trials are done
and much effective drug is formed against the disease. At the same time, it is equally
important to maintain personal hygiene and public hygiene as a primary step till a
better vaccine is discovered.