الفهرس 
History and types of measles vaccineOnly 14 pages are availabe for public view
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Abstract
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SUMMARY
Measles is one of the widely spread diseases
affecting children and early adolescents. In the
developing countries complications of measles contribute
to many deaths especially during the first year of
life.
The trials to introduce a safe and effective
means of induction of active immunity against measles
had started as early as 1749. Since then a series
of scientific researchs have lead to the introduction
of the safe and effective live further attenuated
measles-virus vaccine widely used nowadays.
Since the development of live measles vaccines,
the problem of passively acquired maternal antibodies
which may interfere with mUltiplication of vaccine
virus, and hence alter the immune response have been
a matter of concern. It was proved that these passive
antibodies against measles virus can be detected in
infants 11 - month - old using HI test. Consequently
attack rates in children vaccinated under one year
were significantly higher than in those vaccinated
over 1 year of age. Many serologic studies supporting
this hypothesis have ~een done. Other laboratory and
epidemiologic studies have suggested that a higher
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seroconversion rate and mean antibody titer was obtained
among infants vaccinated at ~15 months of age compared
with those vaccinated at 12-14 months of age.
Our work confirms the results of most of previous
studies using the more sensitive and specific ELISA
technique. The present study have shown a seroconversion
rate of 84.2% among vaccinees who received
the vaccine at <12 months compared to 100% seroconversion
among children vaccinated at ~15 months of
age. The mean antibody titer was significantly higher
in the later group than in the former one (P<O.OOl).
The fact that in the developing countries measles
remains to be an important pUblic health problem during
the second half of the first year of life have made
it wise to recommend mass vaccination’of all susceptible
infants as early as 9 months of age in the shortest
possible period of time. Those who had received the
vaccine at less than 12 months of age during the initial
mass compaign can be successfully revaccinated in the
next year campaign by the time they reach 15 months
of age or more. Using this strategy one may expect
to have a rapid break in the chain of transmission
and in the future complete eradication of measles
may be achievable.
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