Virus-induced secondary bacterial infection: a concise review

Hendaus, Mohamed A; Jomha, Fatima A; Alhammadi, Ahmed H

Viral respiratory tract infections (VRTIs) are very common in children and their presentations vary from simple colds to life-threatening infections. [1] [2] [3] [4] [5] The detection of a respiratory virus does not necessarily infer that the child has only a viral infection, 6 since outbreaks of VRTIs are being linked to increased incidence of bacterial coinfections. 7 The human body is usually capable of eliminating respiratory viral infections with no sequelae; however, in some cases, viruses bypass the immune response of the airways, causing conceivable severe respiratory diseases. 8 Robust mechanical and immunosuppressive processes protect the lungs against external infections, but a single respiratory tract infection might change immunity and pathology. 9 Health care providers often face a dilemma when encountering a febrile infant or child with respiratory tract infection. The reason expressed by many clinicians is the challenge to confirm whether the fever is caused by a virus or bacterium. 10 Acute otitis media (AOM) is a usual bacterial coinfection that occurs in 20%-60% of cases of VRTIs. [11] [12] [13] [14] In addition, almost 60% of children with VRTI have changes in the maxillary, ethmoidal, and frontal sinuses. 11, 12 Moreover, in the year 1918, it was estimated that 40-50 million individuals died from the influenza pandemic, many of which were due to secondary bacterial pneumonia with Streptococcus pneumoniae. 15