Pneumonia is distinct from and should not be confused with bronchitis. Usually, and as is commonly understood, a pneumonia is caused by an infection, most often bacterial , but sometimes viral in origin. Chlamydia can cause pneumonia, especially in very young infants as a consequence of an infection picked up travelling down the birth canal. However, our definition does not exclude pneumonia from other causes, and chief among these is consolidation of a section of the lungs by foreign material, usually vomited food - or aspiration pneumonia. Severely handicapped children who are lying horizontally all the time are at risk for this complication.
Hydrocarbon solvents down in the lungs can cause incredibly bad chemical pneumonias.
A certain furniture polish is an example of a substance pediatricians advise strongly against having in the home at all for just that reason. It has been lethal on quite a few occasions. Ask your doctor about that and remember that child-proof caps are there for a reason. Never buy the regular cap version if you have kids at home and always put it back on properly. The ensuing pneumonia from the inhaled powder has been fatal.