Zika Virus Induces Progressive Morphological and Fibrotic Alterations in the Submandibular-Sublingual Salivary Complex of Immunosuppressed Mice.

To perform a morphological, histochemical, morphometric, and fractal analysis of the submandibular-sublingual salivary complex of immunosuppressed male Balb/c mice experimentally infected with Zika virus (ZIKV), aiming to characterize infection-related structural alterations. A total of 110 male Balb/c mice were immunosuppressed with dexamethasone and inoculated intraperitoneally with ZIKV. Animals were allocated into control and infected groups and euthanized at 14, 21, 28, 35, and 42 days post-infection (dpi). Body weight, salivary gland weight, and organosomatic index were assessed. The glands were processed for histological, histochemical, morphometric, and fractal analyses. Parameters evaluated included collagen deposition, acinar and ductal morphology, epithelial height, lumen area, fractal dimension, and lacunarity. Data were analyzed using the Kruskal-Wallis test with Dunn's post hoc (p < 0.05). ZIKV-infected mice showed transient body weight loss and increased glandular weight and organosomatic index at specific time points. Histopathological changes included ductal tortuosity, vacuolization, increased connective tissue, and higher cellularity. A progressive increase in collagen deposition was observed, indicating fibrosis in both serous and mucous acini, especially after 21 dpi. Morphometric and fractal analyses revealed marked glandular remodeling and increased structural complexity. These findings demonstrate that ZIKV infection induces significant morphological and fibrotic alterations in salivary glands.