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bioRxiv · 10.64898/2026.10.27.762283

Amoxicillin Worsens Mortality from Viral Respiratory Tract Infection

Orlov, M.·Shaw, S. C.·Stoner, S. N.·Fulte, S.·Janssen, W. J.·Clark, S. E.
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Abstract

Influenza infections are common and result in substantial mortality, with secondary bacterial pneumonias contributing to worse outcomes. To prevent mortality associated with bacterial co-infections, antibiotics are often prescribed in the absence of microbiological data. Currently, there are conflicting society recommendations on antibiotic utilization in viral respiratory tract infections as we lack prospective studies to guide treatment. We developed an animal model to study the effects of antibiotic exposure during influenza infection. Our results suggest that amoxicillin started during influenza A infection increases mortality from influenza A and increases severity of secondary bacterial pneumonia, and this is more pronounced in males.

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Orlov, M., Shaw, S. C., Stoner, S. N., Fulte, S., Janssen, W. J., Clark, S. E.. 2026-10-29. Amoxicillin Worsens Mortality from Viral Respiratory Tract Infection. https://doi.org/10.64898/2026.10.27.762283

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