Incidence and Risk of Pneumococcal Pneumonia in Adults with Distinct Underlying Medical Conditions: A Population-Based Study.

PURPOSE: This study investigated the incidence of pneumococcal pneumonia requiring hospitalisation among middle-aged and older adults with and without specific underlying medical conditions, evaluating the influence of these conditions in the risk of developing pneumonia. METHODS: Population-based prospective cohort study included 2,025,730 individuals ≥ 50 years around Catalonia, Spain. The Catalonian information system for the development of research in primary care (SIDIAP) was used to establish baseline characteristics of the cohort (comorbidities and underlying medical conditions). Hospitalisations from pneumococcal pneumonia occurred among cohort members between 01/01/2015 and 31/12/2015 were collected from hospital discharge codes of 68 reference Catalonian hospitals. Cox regression was used to estimate the association between baseline conditions and the risk of developing pneumonia. RESULTS: Global incidence rate (IR) of hospitalised pneumococcal pneumonia was 82.8 cases per 100,000 persons-year. Maximum IRs (per 100,000 persons-year) emerged among persons with haematological neoplasia (837.4), immunodeficiency (709.2), HIV infection (474.7), severe renal disease (407.5) and chronic pulmonary disease (305.7). In the multivariable analyses, apart from increasing age, HIV infection (hazard ratio [HR] 6.78), haematological neoplasia (HR 6.30), prior all-cause pneumonia (HR 5.27), immunodeficiency (HR 4.57) and chronic pulmonary disease (HR 2.89) were the conditions most strongly associated with an increasing risk. Pneumococcal vaccination did not emerge associated with a reduced risk in our study population (nor PPsV23 neither PCV13). CONCLUSION: Old age, immunocompromising conditions and chronic pulmonary/respiratory disease are major risk factors for pneumococcal pneumonia in adults. Our data underline the need for better prevention strategies in these persons.

Incidence of pneumococcal infections among children under 15 years in southern Catalonia throughout the heptavalent conjugate vaccine era, 2002-2009.

PURPOSE: Updating epidemiological studies to document current incidences of pneumococcal diseases are greatly needed in the current era of new pneumococcal conjugate vaccines (PCVs). The aim of this study is to analyze the incidence and distribution of different serotypes causing pneumococcal infections among the pediatric population in southern Catalonia, Spain, throughout the 2002-2009 PCV7 eras. METHODS: A population-based surveillance study was conducted among children aged ≤ 14 years in the region of Tarragona (Catalonia, Spain) during the period 2002-2009. All cases of pneumococcal infections (invasive and non-invasive cases) were included in the study. Incidence rates (per 100,000 population-year) and prevalence of infections caused by serotypes included in different PCV formulations were calculated for the 2002-2005 and 2006-2009 periods. RESULTS: Globally, across the total 2002-2009 period, the incidence of pneumococcal infections was 48.2 per 100,000 children-year (22.4 and 25.8 for invasive and non-invasive infections, respectively). Between 2002-2005 and 2006-2009, the incidence rates largely decreased among children aged <2 years (from 171 to 111 per 100,000 children-year; p = 0.059), but they did not substantially vary among children aged 2-14 years. The percentages of cases caused by serotypes included in PCV7 (60.0 vs. 16.7 %; p < 0.001), PCV10 (75.0 vs. 47.4 %; p = 0.028), and PCV13 (85.0 vs. 70.5 %; p = 0.190) decreased in both periods. CONCLUSION: In this study, which was conducted in a setting with intermediate PCV7 uptakes, a considerable protective direct effect of vaccination occurred among young infants, but an indirect protective effect did not emerge in the rest of the pediatric population. Despite new PCVs with higher serotype coverage, an important proportion of pneumococcal infections is still not covered by these vaccines.