Complement activation in Puumala hantavirus infection correlates with disease severity

Area of Science:

• Immunology
• Virology
• Pathogenesis

Background:

• Hantaviruses, including Puumala virus (PUUV), are significant human pathogens causing renal and cardiopulmonary diseases.
• The precise mechanisms underlying hantavirus pathogenesis remain incompletely understood.

Purpose of the Study:

• To investigate the role of the complement system in the pathogenesis of Puumala virus (PUUV) infection.
• To assess complement activation markers in patients with acute PUUV infection.

Main Methods:

• Measurement of terminal complement complex SC5b-9, and complement components C3 and C4 levels in patients during acute PUUV infection and recovery.
• Evaluation of laboratory parameters and clinical findings related to PUUV-HFRS severity in correlation with complement activation.

Main Results:

• Significantly increased SC5b-9 and decreased C3 levels were observed during the acute stage compared to full recovery.
• Higher SC5b-9 levels correlated with chest X-ray abnormalities in acute PUUV infection.
• SC5b-9 and C3 levels showed significant correlations with clinical and laboratory parameters indicating disease severity.

Conclusions:

• The complement system is activated via the alternative pathway during the acute phase of PUUV infection.
• The level of complement activation correlates with the severity of the acute PUUV infection.
• Complement activation is suggested to contribute to the pathogenesis of acute PUUV infection.