Adverse events following Immunization
(AEFI) surveillance

When delivering influenza vaccine to pregnant women, a surveillance system to monitor and investigate possible AEFI should include the following objectives:

1. Detect and identify problems with vaccines that could be due to the product, its quality or an immunization error in the programme.
2. Evaluate the rate of reactions to the vaccine observed in that specific population and compare it to the expected vaccine reaction rates reported in literature.
3. Ensure that coincidental events are not mistaken for vaccine reactions and affect the confidence in the immunization programme.
4. Facilitate the investigation and causality assessment of individual AEFI reports that are collected when implementing the programme.
5. Identify events that may indicate a previously unknown or unexpected vaccine reaction that can be investigated in more depth.
6. Create awareness of immunization safety in the community and share this information with other programmes and with WHO.

The national immunization programme should work with the national regulatory authority and the district and subnational stakeholders to define the roles and responsibilities that will be assigned to each other.

A checklist for the immunization safety surveillance system can be found in Table 7 of the Global manual on surveillance of adverse events following immunization.

All vaccine recipients who present to the health-care system or are reported from the community as having an event (including minor events) perceived to be related to the influenza vaccine should be reported to the influenza vaccine immunization programme and surveillance system using the standard AEFI reporting form that has been adapted to include details on pregnancy.

For serious AEFI that are investigated, the causality should be assessed by a group of experts, as described in the Causality assessment of an adverse event following immunization (AEFI): user manual for the revised WHO AEFI causality assessment classification.