Novel Influenza A/H1N1 Clinical Trial
Official title:
Short and Long-Term Electronic Surveillance of a Large Number of Healthcare Workers Following Administration of an Adjuvanted Ph1n1 Vaccine
Influenza vaccines are continuously modified to adjust to the virus antigenic shifts or
drifts, and its safety profile may vary. While generally considered safe, influenza vaccines
have been associated in the past with increases in cases of Guillain-Barré syndrome (1976)
or with oculorespiratory syndrome (2001). The emergence of a novel strain of H1N1 influenza
virus (pH1N1) has prompted health departments worldwide to prepare for mass vaccination
campaigns with a new H1N1 pandemic vaccine. Following recommendations of the World Health
Organization (WHO), Canada immunized its population with a dose-sparing adjuvanted vaccine.
While the adjuvant developed by GlaxoSmithKline (GSK) has been administered to over 39 000
people, only a few hundred will have been vaccinated with the H1N1 formulation in clinical
trials before the mass campaign was launched. With this small number, adverse events
occurring at a rate < 1% will not be detected by these clinical trials.
Considering that most cases of pH1N1 to date have been relatively mild, it will be
imperative to rapidly detect adverse events serious enough to reconsider the use of the
vaccine. Passive surveillance is collecting notifications of adverse events but the
sensitivity of this system is not high and its timeliness is not necessarily optimal.
In Canada, healthcare workers (HCW) are among those who were offered the new pandemic
vaccine in priority. Because they were offered the vaccine early in the campaign and because
they constitute a well-defined group in good general health, this group of people may be
well suited for monitoring the safety of the pH1N1 vaccine.
The main objective of this project was to estimate in HCW vaccinated against pH1N1 the
frequency of adverse events of sufficient severity to cause work absenteeism or medical
consultation.
The active surveillance was done in HCW from 3 sites (Canadian hospitals) participating in
the Pandemic Influenza Research Network (PCIRN): (1) Halifax (Nova Scotia), (2) Quebec City
(Quebec): 3 hospitals, (3) Toronto
n/a
Observational Model: Cohort, Time Perspective: Prospective