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Influenza A virus--induced acute otitis media
C A Buchman1, W J Doyle, D P Skoner
1Department of Otolaryngology, University of Pittsburgh School of Medicine, Pennsylvania, USA.
Abstract:
To better understand the significance of viral upper respiratory tract infections in the pathogenesis of acute otitis media (OM), 27 adults underwent intranasal inoculation with influenza A virus. Monitoring consisted of antibody titer determination, tympanometry, and otoscopy. Microbiologic analysis consisted of cultures and polymerase chain reaction (PCR)-based detection for influenza A virus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. All subjects became infected with the challenge virus. By day 4, 16 (59%) developed middle ear pressures of -100 mm H2O or below and 4 (25%) of them developed OM. One subject (4%) developed purulent OM requiring myringotomy for pain relief. Middle ear effusion cultures were negative. PCR analysis of that subject's middle ear effusion and nasal washes were positive for influenza A virus and S. pneumoniae. These findings support a causal role for viral upper respiratory tract infections in the pathogenesis of OM, possibly mediated by middle ear underpressures and viral and bacterial middle ear infection.
Insights
Viral infections like influenza A can cause acute otitis media (OM) by creating middle ear underpressure. This study found influenza A linked to middle ear underpressures and subsequent bacterial infections, supporting a causal role in OM development.
Area of Science:
- Virology
- Otolaryngology
- Infectious Diseases
Background:
- Acute otitis media (OM) is a common condition, often preceded by viral upper respiratory tract infections.
- The precise role of viruses in OM pathogenesis remains incompletely understood.
Purpose of the Study:
- To investigate the significance of viral upper respiratory tract infections, specifically influenza A, in the development of acute otitis media (OM).
Main Methods:
- 27 adults were intranasally inoculated with influenza A virus.
- Monitoring included antibody titers, tympanometry, otoscopy, and microbiologic analysis (cultures and PCR).
- Pathogen detection focused on influenza A virus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.
Main Results:
- All subjects were infected with influenza A virus.
- 16 subjects (59%) developed middle ear underpressures by day 4.
- 4 subjects (25%) developed OM, with one case of purulent OM.
- PCR detected influenza A virus and S. pneumoniae in the middle ear effusion of the purulent OM case.
Conclusions:
- Viral upper respiratory tract infections, such as influenza A, play a significant role in the pathogenesis of acute otitis media.
- Middle ear underpressures and co-infection with bacteria may mediate the development of OM following viral infections.
- Findings support a causal link between viral infections and OM, highlighting potential viral-bacterial interactions.