Role of viral and bacterial pathogens in causing pneumonia among Western Australian children: a case–control study protocol

Bhuiyan, Mejbah Uddin; Snelling, Thomas L; West, Rachel; Lang, Jurissa; Rahman, Tasmina; Borland, Meredith L; Thornton, Ruth; Kirkham, Lea-Ann; Sikazwe, Chisha; Martin, Andrew C; Richmond, Peter C; Smith, David W; Jaffe, Adam; Blyth, Christopher C

We are conducting a prospective case-control study (PneumoWA) where cases are children with radiologically-confirmed pneumonia admitted to Princess Margaret Hospital for Children (PMH) and controls are healthy children identified from PMH outpatient clinics and from local community immunisation clinics. The case-control ratio is 1:1 with 250 children to be recruited in each arm. Nasopharyngeal swabs (NPS) are collected from both cases and controls to detect the presence of viruses and bacteria by polymerase chain reaction (PCR); pathogen load will be assessed by quantitative PCR. The prevalence of pathogens detected in cases and controls will be compared, the odds ratio of detection and population attributable fraction to CAP for each pathogen will be determined; relationships between pathogen load and disease status and severity will be explored.