Seasonal influenza vaccination uptake in Quebec, Canada, 2 years after the influenza A(H1N1) pandemic.

Background: A decrease in seasonal influenza vaccine uptake was observed after the influenza A(H1N1) pandemic in 2009. The goal of our study was to assess seasonal influenza vaccine uptake in 2011-2012, 2 years after the influenza A(H1N1) pandemic mass immunization campaign and to identify the main reasons for having or not having received the vaccine.

Methods: A telephone survey using random-digit dialing methodology was conducted.

Impact of 2+1 pneumococcal conjugate vaccine program in the province of Quebec, Canada.

Background: Quebec was the first jurisdiction in the world to recommend a 3-dose (2+1) pneumococcal conjugate vaccine (PCV) schedule. The program was implemented in December 2004 with a catch-up for children <5 years. PCV-7 was first used and replaced, respectively, by PCV-10 in 2009 and by PCV-13 in 2011.

Largest measles epidemic in North America in a decade--Quebec, Canada, 2011: contribution of susceptibility, serendipity, and superspreading events.

Background: The largest measles epidemic in North America in the last decade, occurred in 2011 in Quebec, Canada, where rates of 1- and 2-dose vaccine coverage among children 3 years of age were 95%-97% and 90%, respectively, with 3%-5% unvaccinated.

Methods: Case patients identified through passive surveillance and outbreak investigation were contacted to determine clinical course, vaccination status, and possible source of infection.

Results: There were 21 measles importations and 725 cases.

The changing epidemiology of meningococcal disease in Quebec, Canada, 1991-2011: potential implications of emergence of new strains.

Background: In order to inform meningococcal disease prevention strategies, we analysed the epidemiology of invasive meningococcal disease (IMD) in the province of Quebec, Canada, 10 years before and 10 years after the introduction of serogroup C conjugate vaccination.

Methodology: IMD cases reported to the provincial notifiable disease registry in 1991-2011 and isolates submitted for laboratory surveillance in 1997-2011 were analysed. Serogrouping, PCR testing and assignment of isolates to sequence types (ST) by using multilocus sequence typing (MLST) were performed.

Long-lasting measles outbreak affecting several unrelated networks of unvaccinated persons.

Despite a population immunity level estimated at approximately 95%, an outbreak of measles responsible for 94 cases occurred in Quebec, Canada. Unlike previous outbreaks in which most unvaccinated children belonged to a single community, this outbreak had cases coming from several unrelated networks of unvaccinated persons dispersed in the population. No epidemiological link was found for about one-third of laboratory-confirmed cases.