To determine the proportion of hospitalized pneumonia cases in children aged 60 months or less associated with vaccine-preventable Streptococcus pneumoniae serotypes (4, 6B, 9V, 14, 18C, 19F, 23F).

Subjects meeting the eligibility criteria, including parental informed consent to collect clinical-epidemiological information, will have a deep respiratory aspirate specimen to determine the etiology of the lower respiratory tract infection. Clinicians may obtain other diagnostic specimens, such as pleural fluid, lung tap, cerebrospinal fluid, nasopharyngeal culture, or serum for serological assays, as indicated clinically. The chest radiograph will be taken and read locally according to predetermined criteria and by staff radiologists trained in radiographic criteria for pneumonia. Bacterial isolates other than Streptococcus pneumoniae will be identified according to standardized procedures. S. pneumoniae isolates will be transported to central laboratories for confirmation of identity, serotyping and antibiotic resistance testing, using standard techniques. Serotype will be determined using type-specific sera (Quellung reaction). Antibiotic susceptibility to penicillin, cefuroxime, ceftriaxone, erythromycin, Amoxycillin, Ofloxacin, Vancomycin, and imipenem be conducted using E-test according to standardized procedures at the central facilities.

Inclusion Criteria:

• Age, 60 months or less
• Meets study criteria for clinical pneumonia
• All the examination are/can be done within (before or after) 72 hours to enrollment time
• Informed consent obtained from parent or guardian

Exclusion Criteria:

• Received any pneumococcal vaccine in the past
• Current or underlying conditions that would pose a hazard in obtaining the deep respiratory aspirate (e.g., bleeding diathesis, severe respiratory compromise and others as determined by clinician) Aspirates may be obtained from patients who are intubated
• Any other medical condition that in the opinion of the clinician/investigator would pose a hazard to the child by participating in the study
• Children with recurrent pneumonia will enter into the study on only one occasion

Hospitalized children with pneumoniae less than 5 years,located in Tianjin Children's Hospital