Does influenza A infection increase oxidative damage?

Area of Science:

• Biochemistry
• Immunology
• Pathogenesis

Background:

• Oxidative damage is increasingly implicated in the pathogenesis of various infections, including influenza.
• Understanding the temporal dynamics of oxidative stress markers during and after influenza is crucial for elucidating disease mechanisms.

Purpose of the Study:

• To investigate temporal changes in oxidative damage biomarkers in adult influenza A patients.
• To correlate these oxidative damage markers with clinical parameters and persistent post-influenza symptoms.

Main Methods:

• Prospective cohort study of 35 adult influenza A patients.
• Collection of clinical data and blood samples during acute illness and at 3-month follow-up.
• Measurement of plasma F2-isoprostanes, total hydroxyeicosatetraenoic products (HETEs), cholesterol oxidation products, gamma-glutamyltransferase, and high-sensitivity C-reactive protein (hsCRP).
• Administration of a fatigue questionnaire at 3-month follow-up.

Main Results:

• Influenza patients showed significantly increased levels of multiple oxidative damage biomarkers during acute illness compared to controls.
• Elevated biomarker levels persisted at 3 months post-infection, despite clinical recovery.
• Patients with persistent fatigue had higher baseline F2-isoprostanes and HETEs.
• Patients with persistent myalgia and arthralgia had higher baseline hsCRP.

Conclusions:

• Oxidative damage is a significant feature of acute influenza infection and can persist beyond clinical recovery.
• Persistent oxidative stress may play a role in the development of post-influenza symptoms, particularly fatigue and musculoskeletal pain.
• These findings support a hypothesis linking oxidative damage to influenza pathogenesis and post-infectious sequelae.