Page 148 - Pharmaceutics IV (02-06-01305)

Poliomyelitis virus infects human tissue without effect on

Rabbit tissue.

Immunity after infection : 1-permenant e.g.measles,

Smallpox or yellow fever.

2-Transient : Influenza , common cold .

Infection with virus altered the cell susceptibility ,thus
having a marked effect on reinfection.After the majority of
virus infections or injections of virus vaccine, the initial high
antibody titre falls but there is a rapid response to a
booster dose.

Action of humoral immunity

ntibodies render the bacterium more susceptible to
phagocytoris.

Measurement of man response to virus diseases and
vaccines by : 1-Neutralization

Constant dose of virus + serum dilutions----incubate----
inoculate into animals or cell cultures. Infection occur
when the serum has been diluted beyond the point of
neutralization.

2- Serological test : Agglutination or precipitation of virus
by antiserum

Interaction of virus and antibodies :

Antiserum added to cell culture before addition of virus

-3-