Abstract:
Background: Vaccination is one of the most cost effective public health interventions. Real or perceived adverse events following immunization (AEFI) can however undermine the credibility of a vaccine and an immunization programme. Ghana rolled out a measles-rubella combined vaccine in a mass immunization campaign in September, 2013. We assessed the AEFI associated with the vaccine in Jirapa District to obtain base-line data and appropriately respond to public concerns on safety issues.
Method: A risk interval cohort study was conducted. Three hundred and fifty children aged 9 months -14 years were followed for twelve weeks. Seventy children in four age groups were selected from each of five communities in Jirapa District using modified WHO EPI coverage guideline. Participants were observed for four weeks before vaccination then eight weeks after vaccination for adverse events in the pre and post vaccination control windows and risk window. An AEFI was defined as any medical incident, which occurred after vaccination with measles rubella vaccine. An AEFI was said to be serious if it was life-threatening and required intervention and/or hospitalization or resulted in disability/incapacity or death. Univariate and bivariate analysis were done using Epi info 3.5. P values less than 0.05 were considered statistically significant.
Results: Three hundred and fifty (350) vaccinees, 51.6%(180/350) females and 48.4%(170/350) males were followed for twelve weeks. Overall incidence of adverse events following immunization was 5.1% (95% CI: 3.2-8.2%). Of these fever accounted for 66.7% (12/18), febrile convulsion 5.6% (1/18), headache 16.7% (3/18), skin rashes 5.6 (1/18), and pain at injection site 5.6 (1/18). Only two (11.1%) of the adverse events were serious. Three (16.7%) of the adverse events occurred within 24 hours after vaccination while 11 (61.1%) occurred between the first and seventh day after vaccination. Children aged 9months- 3 years were 6.6 times more likely to develop fever than children aged 10-14 years (RR=6.6, 95% CI: 0.83-52.62; P <0.04).
Conclusion: The adverse events following immunization with measles-rubella vaccine were few and generally mild. The Public should be encouraged to take the vaccine while surveillance for adverse events and investigation of serious ones is sustained.
