Impact of pneumococcal vaccines use on invasive pneumococcal disease in Nunavik (Quebec) from 1997 to 2010

Abstract

BackgroundIn 2000, an outbreak of severe pneumonia caused by a virulent clone of serotype 1 Streptococcus pneumoniae was detected in the Nunavik region of Quebec. A mass immunization campaign was implemented in the spring of 2002, targeting persons ≥5 years of age and using the 23-valent pneumococcal polysaccharide vaccine (PPSV23). At the same time, the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced into the routine immunization programme of infants, with catch-up for children up to 4 years of age.ObjectivesTo describe the epidemiology of invasive pneumococcal disease (IPD) in relation to PPSV23 and PCV7 use.Study design and methodsRetrospective analysis of IPD cases identified by the Quebec public health laboratory during the period 1997–2010.ResultsA total of 82 IPD cases were identified during the study period. In adults, serotype 1 incidence decreased following the 2002 PPSV23 mass campaign but breakthrough cases continued to occur. Following PCV7 use in children, there was a decrease in the incidence of vaccine-type IPD and replacement by other serotypes in adults. In children, a marked decrease in the annual incidence of serotypes included in PCV7 was observed following PCV7 introduction: 162/100,000 in 1997–2001 vs. 10/100,000 in 2004–2010 (p<0.01). Concomitantly, the incidence of IPD caused by serotypes not included in PCV7 increased from 29/100,000 to 109/100,000 (p=0.11).ConclusionThe mass immunization campaign using the PPSV23 in 2002 and the introduction of PCV7 for the routine immunization of infants induced important modifications in the epidemiology of IPD. IPD rates in Nunavik remain much higher than in the southern part of the province both in children and adults. More effective pneumococcal vaccines are needed to eliminate geographic disparities in IPD risk.

Pneumococcal Vaccine and Patients with Pulmonary Diseases

“…(6) Although invasive pneumococcal disease may occur with all serotypes, almost 60% of cases are caused by the same 23 serotypes. (7, 8) Furthermore, certain serotypes seem to be more commonly isolated from specific organ systems. For instance, serotype 1 and 3 are more frequently isolated in pneumonia and serotypes 6, 10 and 23 are regularly isolated in meningitis.…”

Food insecurity, vitamin D insufficiency and respiratory infections among Inuit children

“…Despite the introduction of a 7-valent pneumococcal conjugate vaccine (PCV7) in 2002 and the 13-valent vaccine (PCV13) in 2010 in Northern Canada, pneumococcal pneumonia remains a major issue ( 5 ). Studies examining the effect of PCV7 in Northern communities have found that while there has been a decrease in invasive pneumococcal disease caused by serotypes included in the vaccine, there was an increase in disease caused by serotypes not included in PCV7 ( 6 , 7 ). A number of risk factors have been associated with respiratory disease prevalence and/or severity in Inuit children, including household overcrowding, passive and in utero smoke exposure, lack of breastfeeding and reduced ventilation in the house ( 8 , 9 ).…”

Bacterial Vaccinations in Patients with Chronic Obstructive Pulmonary Disease

“…To date, 98 different serotypes of S. pneumoniae were identified, with 23 of them being the major cause of invasive pneumococcal diseases [ 20 , 21 ]. The most common isolate is serotype 14, followed by 1, 5, 6A, 6B, 19F, 23F serotypes, which can be found in more than 50% of patients [ 22 ].…”