Impact of Introduction of PHiD-CV for Nunavik Children, Quebec, Canada

Around 1420 children born between 2006 and 2010 had been eligible to routine immunization program with pneumococcal vaccines. The objective of this study is to document the residual burden of acute upper respiratory infections (AURIs), acute lower respiratory infections (ALRIs), otitis media (OMs) and auditory functional and anatomical abnormalities in children under the age of 5 years in Nunavik who will be exposed to PHiD-CV in combination with PCV-7 or PCV-13. The comparison groups will be the cohorts of children who received no PCV vaccine (those born in 1994-1996) and those exposed to PCV-7 exclusively (those born in 2003-2007). The specific objectives are to measure in children under the age of 5 years in Nunavik and born in the period 2009 to 2010: 1. the incidence of invasive pneumococcal disease(IPD), AURIs, ALRIs and OMs; 2. the frequency of antibiotic treatments due to these diseases; 3. the frequency of hospitalizations and transfers to the South on account of ALRIs; 4. the frequency of tympanotomies and ventilation tube insertions; 5. the prevalence of anatomical and functional lesions of the middle ear at the age of 5 years (the main issue). The main research hypothesis is that the incidence of AURIs, ALRIs and OMs and the prevalence of sequelae from OM decreased after the implementation of PHiD-CV in 2009, as compared with previous cohorts of children who were not exposed to this new vaccine.