Do school holidays affect adult pneumococcal community acquired pneumonia incidence?

Abstract

Background: Child contact is a risk factor for adult pneumococcal disease. We hypothesised that school holidays would be associated with increased rates of adult non-invasive pneumococcal community acquired pneumonia (CAP), due to changes in child contact patterns and transmission of Streptococcus pneumoniae . Methods: Between September 2008 and 2013, adults admitted with CAP to 2 hospitals that covered the catchment area of Greater Nottingham, were studied prospectively. Pneumococcal infection was determined by identification of the organism from sterile sites (bacteraemia) and detection of pneumococcal antigen or pneumococcal serotype in urine samples. Multivariable and Poisson regression models were used to calculate the odds of pneumococcal CAP and relative incidence during school holiday and term periods. Results: Of 2221 individuals, 644 (29.0%) were diagnosed with pneumococcal CAP. Of those with pneumococcal CAP, 203 (31.5%) were admitted during school holiday periods. Admission during school holidays was independently associated with a diagnosis of pneumococcal CAP, after adjustment for variables including child contact. The age-adjusted incidence rate ratio of pneumococcal CAP during school holidays compared to term time was 1.35 (95%CI 1.14-1.59, p Conclusion: Our results demonstrate a higher incidence of pneumococcal CAP in adults hospitalised during school holiday periods compared to term-time. Duration and intensity of child contact may play an important role in pneumococcal disease transmission to adults.