Oxidative Stress, Glutathione System Activity, and Zinc/Selenium Imbalance in Adult Measles of Varying Severity According to Vaccination Status

Background: Adult measles is increasingly associated with severe clinical manifestations, particularly among unvaccinated individuals. Oxidative stress and micronutrient depletion may contribute to disease severity; however, integrated data evaluating oxidative protein damage, glutathione system activity, and zinc/selenium status in adult measles remain limited. This study assessed oxidative stress markers, glutathione-dependent enzymes, and trace element levels according to vaccination status. Methods: Eighty adults with laboratory-confirmed measles were stratified into vaccinated (n=40) and unvaccinated (n=40) groups. Oxidative protein modification was quantified spectrophotometrically at 356, 370, 430, and 530 nm. GPx and GR activities were measured using standard assays. Serum zinc and selenium concentrations were determined by atomic absorption spectrophotometry. Statistical analyses included distribution testing, group comparisons with Holm correction, and standardized effect size estimation. Results: Unvaccinated patients demonstrated higher protein carbonyl levels at 356 nm (1.474 ± 0.148 vs 1.266 ± 0.041; p=0.005) and 370 nm (p<0.01), along with lower GR activity (0.048 ± 0.007 vs 0.061 ± 0.003; p=0.035). Effect size analysis showed a large between-group difference for GR activity (Hedges g≈0.89) and moderate effects for oxidative indices. Zinc levels were reduced by 24% in unvaccinated and 13% in vaccinated patients (78.7 ± 0.72 vs 89.5 ± 0.78 µg/dL; p<0.001). Selenium levels were decreased by 55% and 49%, respectively (61.3 ± 0.49 vs 69.8 ± 0.56 µg/L; p<0.001). Conclusion: Adult measles was associated with oxidative protein modification, impaired glutathione system activity, and reduced zinc and selenium levels, particularly in unvaccinated patients. These findings are associative and require confirmation in prospective longitudinal studies.