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Increased pharyngeal bacterial colonization during viral illness

C H Ramirez-Ronda, Z Fuxench-López, M Nevárez

    Archives of Internal Medicine
    |November 1, 1981
    PubMed

    Insights

    Upper respiratory tract infections increase oropharyngeal colonization by Staphylococcus aureus and Gram-negative bacilli (GNB). This transient increase may elevate pneumonia risk, highlighting the importance of monitoring bacterial colonization during illness.

    Area of Science:

    • Microbiology
    • Infectious Diseases
    • Clinical Medicine

    Background:

    • Oropharyngeal colonization by pathogens like Staphylococcus aureus and Gram-negative bacilli (GNB) is a known risk factor for infections.
    • Understanding colonization dynamics during illness is crucial for infection prevention strategies.

    Purpose of the Study:

    • To investigate the prevalence and duration of oropharyngeal colonization by S. aureus and GNB in healthcare professionals.
    • To determine if upper respiratory tract infections (URTIs) alter this colonization.

    Main Methods:

    • Biweekly quantitative oropharyngeal cultures were performed over 11 months in 89 house staff officers.
    • Episodes of URTIs were documented, and colonization rates were compared between illness-free and URTI periods.

    Main Results:

    • Baseline GNB colonization ranged from 12-18%; S. aureus colonization ranged from 5-14%.
    • During URTIs, GNB colonization increased to 60% and S. aureus to 43%.
    • Increased colonization was transient, lasting approximately two weeks.

    Conclusions:

    • URTIs significantly increase oropharyngeal colonization by S. aureus and GNB.
    • This transient increase in bacterial colonization during URTIs may contribute to the heightened risk of pneumonia.

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