Table 1.

Common pathogens concerned in respiratory tract infections (bacteria, viruses, and fungi).

Pathogen	Type gram	Pathology	Ref.
Streptococcus pneumoniae	+	Bacterial pneumonia	[1, 2]
Haemophilus influenzae	−	Pneumonia, sinusitis	[3, 4]
Chlamydophila pneumoniae	Obligate intracellular bacterium	Atypical pneumonia	[5, 6]
Staphylococcus aureus	+	Sinusitis, pneumonia	[7, 8]
Pseudomonas aeruginosa	−	Sinusitis, pneumonia	[9]
Legionella pneumophila	−	Cough with sputum, bronchiolitis	[10, 11]
Moraxella catarrhalis	−	Bronchitis, sinusitis, and bronchopneumonia	[12]
Rhinoviruses	Enterovirus	Common cold and sinusitis	[13]
Coronaviruses	Coronavirinae	Pneumonia	[14, 15]
Respiratory syncytial virus	Pneumovirus	Bronchiolitis	[16]
Adenovirus	Adenoviridae	Pneumonia and tonsillitis,	[17]
Herpes simplex virus	Respirovirus	Pneumonia	[18, 19]
Histoplasma capsulatum	Histoplasma (dimorphic fungi)	Pneumonia	[20]
Cryptococcus neoformans	Cryptococcus (yeast)	Pneumonia	[21, 22]
Coccidioides immitis	Coccidioides (pathogenic fungus)	Pneumonia	[23, 24]
Pneumocystis jirovecii		Pneumonia	[25, 26]