Sample | Pathogen/antigen | Tests | Diagnosis of causative pathogens# | |
2001–2002 study | 2009–2011 study | |||
Serum | Respiratory viruses | Complement fixation | Complement fixation | Acute titre ≥1/128 or four-fold rise between paired sera |
Atypical bacteria | ||||
Mycoplasma | IgM antibody | IgM antibody | Positive | |
Group A Streptococcus | ASOT (IU·mL−1) | ASOT (IU·mL−1) | Acute two-fold rise or four-fold rise between paired sera | |
Blood | Bacteria | Culture | Culture | Growth |
Streptococcus pneumoniae | Real-time PCR | Real-time PCR | Positive | |
Nasopharyngeal secretions/sputum | Respiratory viruses | IFAT | Real-time PCR | Positive |
Bacteria | Culture | Culture/real-time PCR | Not applicable | |
Tracheobronchial secretions (bronchoalveolar lavage/endotracheal) | Respiratory viruses | IFAT | Real-time PCR | Positive |
Bacteria | Culture | Culture/real-time PCR | Growth/positive | |
Pleural fluids | Bacteria | Culture | Culture | Growth |
Pneumococcal antigen | ELISA | ELISA | Positive | |
Streptococcus pneumoniae | Not tested | Real-time PCR | Positive |
ASOT: antistreptolysin O titre; IFAT: immunofluorescence antibody testing. #: definite/probable.