Abstract
Background: Vaccination is one of the major successful public health interventions worldwide, protecting global populations from most of the health-impairing infections. But as like other medications, vaccines also can cause various forms of adverse effects. The need of this study was to analyze the pattern of an adverse event following immunization (AEFI) in children of Puducherry population and to detect any new and rare AEFI.

Aims and Objectives: Objectives of this study were to find out the pattern of known adverse events and to identify any new, unusual and rare AEFI in pediatric age group and work out causality assessment for all the AEFI.

Materials and Methods: In this observational cross-sectional study, AEFI was collected from the pediatric outpatient department of our institute, between the month of August and September 2016 and analyzed for causality assessment.

Results: In this observational cross-sectional study conducted for a period of 2 months from August 2016 to September 2016 in MGMC and RI, Puducherry 63 nonserious suspected AEFI were reported, and it represents 19% of the vaccinated children. No rare or any serious suspected AEFI was reported during the study period. The most common AEFI was fever (44.4%) followed by fever along with swelling at the injection site (22%). The maximum AEFI was reported due to the pentavalent vaccine (46%), followed by DPT + OPV vaccine (21.5%) combination. On causality assessment, we have found that 87% of AEFI were indeterminate while 13% have a consistent causal association to immunization.

Conclusion: The benefit of all the vaccines is undeniable; however, they need to be taken with caution and care. To overcome under-reporting, all the pediatricians should be accustomed to report any type of AEFI of different levels of severity. Even more, awareness can be created among the parents and teach them the importance of immunization. To improve effective reporting and for further analysis, all tertiary care centres should maintain a proper database of all vaccinated children and detailed reports of all AEFI.

Key words: Vaccine vigilance; Pharmacovigilance; Adverse Event Following Immunization