Examining the bacteria and viruses in the noses of children could give clues to improve the diagnosis and treatment of severe lung infections, a new study has found.
Lung infections are a leading cause of death in under-fives worldwide.
The study found the make-up of bacteria and viruses was altered in the noses of children with respiratory infections.
Researchers say the study helps explain why some children are more prone to developing infections than others.
It could also be key to preventing serious lung infections.
Researchers at the University of Edinburgh found that the differences indicated the severity of the condition and could help doctors predict how long the child needs to stay in the hospital.
They said that in less serious cases, it could reduce the need for antibiotics and help some children recover naturally.