Tracking vaccine lot lifecycles using reports to the vaccine adverse event reporting system (VAERS).
PURPOSE: There is currently no systematically available information available on how rapidly a specific lot of vaccine is used once distributed. We used data from reports to the Vaccine Adverse Event Reporting System (VAERS) to develop a proxy means of surveillance for the lifecycle of selected vaccine lots.
METHODS: A convenience sample, consisting of selected lots of: diphtheria, tetanus, and acellular pertussis (DTaP), Haemophilus influenzae type b (Hib), Hepatitis B, and varicella vaccines, was selected for lifecycle analysis. Assuming that circulation of a vaccine lot is proportional to vaccine-specific adverse event (AE) reporting for that vaccine type, we constructed Gamma distributed usage models and compared them with lot-specific VAERS reports to estimate the actual lifecycle of lots in the system.
RESULTS: Evidence of lot circulation was detected within 1-2 months, and a peak was observed 3-4 months after the vaccine release date for most of the study vaccines. Ninety percent of the vaccine doses in each lot were estimated to be used within 5-9 months of distribution. The length of time a vaccine lot was in use ranged from 5 to 17 months from earliest vaccination date.
CONCLUSIONS: Our modeled and inferred administration of the selected lots of different vaccines were concordant. This method may be useful for spatial and temporal tracking of vaccine lot utilization.
|投稿者||Dayan, Gustavo H; Iskander, John; Glasser, John; English-Bullard, Roseanne; Fullerton, Kathleen E; Chen, Robert|
|ジャーナル名||Pharmacoepidemiology and drug safety|
|組織名||Epidemiology and Surveillance Division, National Immunization Program, Centers;for Disease Control and Prevention, Atlanta, GA 30333, USA. email@example.com|