Prevention and monitoring of adverse events following immunization (AEFI) via a specialized counseling center: A model of surveillance

Abstract Rationale A Centre for AEFI prevention and surveillance, named "Green Channel", was established in Veneto region of Italy to improve vaccine safety. Methods The activity includes: 1) pre-vaccination Counseling Service; 2) wire consultation service on general and specific cases regarding AEFIs and contraindications (CI); 3) surveillance system for analysis and classification of AEFIs reported in the Region. We report the data on the evaluation of 543 subjects, referred for previous AEFI or suspected CI, via a specialized pre-vaccination counseling, through accurate anamnesis, and, when indicated, specialist consultation from other disciplines, specific in vivo and in vitro tests. Finally, personalized instructions for vaccination, temporary suspension or exemption were given. Results In the 1992-2001 period, 543 patients were referred: 241 for previous AEFIs and 302 for CI. The reported AEFIs included 21 local reactions and 220 systemic events. Allergic, neurologic and immune system disorders were frequently submitted as CI. The final advice on the 543 cases indicated vaccination in 389 cases (72%). Temporary suspension or exemption was requested in 52 (10%)and 48 cases (9%), respectively. The vaccination was actually administered to 258 (66%) subjects, with no serious reactions. Conclusions The Centre is proposed as model of surveillance to improve safety, confidence on immunization and information to health officials.