*4.2.1.2 Chlamydial pneumonia among infants*

This type of pneumonia typically occurs at age 1–3 months and is a subacute pneumonia. Characteristic signs include a repetitive staccato cough with tachypnea and hyperinflation and bilateral diffuse infiltrates on a chest radiograph. Peripheral eosinophilia (≥400 cells/mm3) occurs frequently. Considering that this clinical presentation is broad, symptoms of pneumonia in infants aged 1–3 months and especially those whose mothers have a history of are at risk for or suspected of having a chlamydial infection should be tested for C. trachomatis and treated if infected. Mothers at risk include aged <25 years and those aged ≥25 years who have a new sex partner, more than one sex partner, a sex partner with concurrent partners, or a sex partner who has or had a sexually transmitted disease/infection.
