• pneumonia
• respiratory infection
• viral infection
• bacterial infection
• paediatric lung disaese

Emergency department physicians and paediatricians frequently have to decide how best to manage community-acquired pneumonia (CAP). For a febrile child who has increased respiratory effort, oxygen requirement and a chest X-ray (CXR) consistent with lobar pneumonia, the decision to commence antibiotic therapy is straightforward. However, other patients may present more of a dilemma. What about children with respiratory symptoms but only a low-grade (<38°C) fever? Or children whose respiratory symptoms are sufficient to require admission, but whose CXR is equivocal? Current British Thoracic Society (BTS) guidelines state all children with a clinical diagnosis of CAP should be given antibiotics.1 However, with increasing concern about antimicrobial resistance, consideration needs to be given to the likelihood of a bacterial cause.

The BTS guidelines also suggest that microbiological diagnosis, which could separate out viral and bacterial causes, should only be attempted in children with severe CAP needing paediatric intensive care, but not those with milder disease.1 However, these guidelines are 7 years old, and were based on studies that predate the inclusion of pneumococcal conjugate vaccines (PCV13, Pfizer) into many immunisation regimens. Similarly, multiplex polymerase chain reaction (PCR) was not as widely or as relatively cheaply available.

In this issue of Thorax, Bhuiyan et al assess the extent to which viruses and bacteria contribute to childhood CAP in Perth, Western Australia, where pneumococcal vaccination rates are over 90% and influenza vaccine is provided for preschool children over 6 months and high-risk older children.2 3 In a case–control study, they recruited 230 children aged <18 years presenting to hospital with CAP …