1240. Trends of severity and outcomes of patients with pneumococcal pneumonia in relation to seasonality in northern and southern hemipsheres
Session: Poster Abstract Session: Clinical Infectious Diseases: Respiratory Infections
Friday, October 28, 2016
Room: Poster Hall

Despite efficacious antibiotics and vaccines, pneumococcal pneumonia remains a major cause of morbidity and mortality. Although incidence of invasive pneumococcal disease has demonstrated a seasonal course in temperate climates, with incidence peaking in winter months, the forces which drive this seasonality remain poorly understood. Understanding the trends of pneumococcal pneumonia can aid prevention of pneumococcal pneumonia mortality. In this study, we investigated the trends and outcomes of patients with invasive pneumococcal pneumonia in relation to seasonality in the northern and southern hemispheres.


We analyzed data from the Community Acquired Pneumonia Organization database, a database of worldwide cases of community-acquired pneumonia in adults. Inclusion criteria for our analysis were patiens with time to clinical stability greater than 0 days, and blood cultures positive for Streptococcus pneumoniae. Exclusion criteria included residence in tropical regions and positive cultures for Streptococcus pneumoniae in sites other than the blood. Prevalence by season was analyzed by chi square test. Mortality by season was analyzed by multivariable logistic regression, adjusting for pneumonia severity index score, need for ICU admission, history of chronic obstructive pulmonary disease, and pneumococcal bacteremia. Time to clinical stability and length of hospital stay were analyzed using Kaplan Meier survival curves. 


Of 4,507 cases of pneumococcal pneumonia, 425 cases met the criteria for analysis. Winter, spring, summer, and fall accounted for 36%, 29%, 9%, and 26% of the cases, respectively.  There was a significant decrease in the incidence of invasive pneumococcal pneumonia during the summer (p<0.001). Of the 425 cases, 317 (75%) occurred in the northern hemispheres and 108 (25%) in the southern hemisphere. There was no significant difference in mortality, time to clinical stability, or length of hospital stay between these two groups.


Streptococcus pneumoniae is the most common etiological agent of pneumonia and remains a major cause of mortality worldwide. In our study, prevalence of pneumococcal pneumonia exhibited a marked seasonality in both southern and northern hemispheres. However, we found no association between clinical outcome and this seasonality

Ahmed Babiker, MBBS1, Jose Bordon, MD, PhD2, Jennifer Fuh, DO, MSc2, Siddartha Bhandary, MD, MPH2, Julio Ramirez, MD3 and Timothy Wiemken, PhD4, (1)Internal Medicine, Providence Hospital, Washington, DC, (2)Section of Infectious Diseases, Providence Hospital, Washington, DC, (3)Clinical and Translational Research Support Unit, University of Louisville, Louisville, KY, (4)Division of Infectious Diseases, University of Louisville, Louisville, KY


A. Babiker, None

J. Bordon, None

J. Fuh, None

S. Bhandary, None

J. Ramirez, None

T. Wiemken, None

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