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Table 1 Pathogens commonly associated with pneumonia or acute lower respiratory tract infection in children less than 5 years of agee

From: Encouraging rational antibiotic use in childhood pneumonia: a focus on Vietnam and the Western Pacific Region

Age group Bacteria Viruses
<5 years Streptococcus pneumoniae a
Haemophilus influenzae a
Mycoplasma pneumoniae b
Staphylococcus aureus
Klebsiella pneumoniae
Streptococcus pyogenes
Bordetella pertussis c
Mycobacterium tuberculosis d
Influenza virus (A and B)
Parainfluenza virus
Human metapneumovirus
Human corona virus
Neonates Group B streptococcus
Listeria monocytogenes
Enteric (gram negative) bacteria
Chlamydia trachomatis
  1. RSV Respiratory Syncytial Virus, Staphylococcus aureus includes methicillin resistant strains (MRSA); Haemophilus influenzae includes type b and other encapsulated strains
  2. aDisease greatly reduced in settings with universal access to conjugated vaccines; bTypically considered as “atypical bacteria” requiring macrolide therapy; cmainly in unvaccinated babies, in older children it can present as a chronic cough; dThe risk of tuberculosis is dependent on the likelihood of Mycobacteria tuberculosis exposure/infection, which is a particular problem in areas with uncontrolled tuberculosis transmission
  3. eAdapted from [3, 6]