Seroprevalence was done to evaluate the vaccination programme efficacy
in children 1-6 years old at Benha. Antibodies to measles and polio were
measured together with evaluation of vaccination status.In 182 children
studies, vaccine coverage was found to be 85% for measles and over 93%
for polio and diphtheria, pertussis and tetanus. It was not an easy task to
determine the vaccine failure rate accurately; 21% of children were seronegative
after having received measles vaccine, 27% who had apparently not
been vaccinated had antibodies, while a total of 28% had no measles antibodies.
Thirty-four percent of children failed to demonstrate antibodies to
all 3 types of poliovirus after having received 3 doses of oral polio vaccine,
92% had immunity against type 2, and 79% and 77% were immune to
types 1 and 3 respectively.Reasons for diminished effectiveness of vaccination
programmes are cited; and in this study it was probably due to decreased
efficiency of the vaccine due to inadequacies in the cold-chain-
Seroprevalence studies are helpful, but only after vaccine coverage and the
cold-chain have been optimised to the set standards. |
