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


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

BMJ Open 2018, 16;8(3):e020646. DOI: 10.1136/bmjopen-2017-020646

This is the first case–control study in Australia to determine the aetiology and relative contribution of respiratory viruses and bacteria to childhood pneumonia during the postpneumococcal vaccination era.

The study design will estimate how much each respiratory pathogen attributes to childhood pneumonia at a population level after adjusting for demographic factors, pre-existing chronic medical conditions and the presence of other respiratory pathogens.

Prospective recruitment of frequency matched cases and controls in each age group will adjust the effect of age and pathogen seasonality in causing pneumonia in children.

Cases are defined as children with radiologically confirmed pneumonia which reduces the interobserver variability and increase the generalisability of the study data.

Specimens to detect respiratory viruses and bacteria will be collected from the upper respiratory tract (nasopharynx) instead of the actual site of infection, that is, lower respiratory tract. Pathogens detected in nasopharyngeal swab do not necessarily confirm the presence of the same pathogens in the lower respiratory tract; however, evidence of these pathogens in nasopharynx has been found to be associated with lower respiratory tract infection in children in previous epidemiological studies.