July 16, 2026

Long-term Ocular Symptoms Following COVID-19 Linked to Immune Dysregulation, Dysautonomia and Peripheral Neuropathy
These are results from a prospective cross-sectional study that examined persistent ocular symptoms (POS) emerging in non-hospitalized individuals after COVID-19, with individuals without POS post-recovery as controls. Using symptom and quality of life data, clinical examinations and biofluid proteomics, they documented ocular symptoms persisting from three months up to three years post-infection. POS persistent ocular symptoms led to significant vision disability and was linked to clinical findings not detectable in routine exams but only with specialized tests. POS included near vision disturbances, strabismus, weakened autonomic pupillary reflexes, corneal neurodegeneration and chronic activation of ocular surface dendritic/T cells. Diagnostic models based on clinical examinations with or without biomarkers predict POS with 77-91% accuracy and implicate chronic T cell-mediated neuroinflammation in the pathogenesis of POS, a debilitating syndrome arising after COVID-19 recovery and characterized by strabismus, ocular dysautonomia and peripheral ocular neuropathy.

Vagal Cholinergic Denervation of the Gastric Mucosa in Long-COVID-19: In Vivo Evidence of Structural Autonomic Dysfunction
Authors conducted a case–control study including 12 patients with Long-COVID-19 and eight control subjects undergoing routine gastroscopy. Gastric mucosal biopsies were analyzed using immunohistochemistry with the pan-neuronal marker protein gene product 9.5 (PGP 9.5) and vasoactive intestinal peptide (VIP) as a marker of cholinergic fibers. Nerve fiber density was quantified in both fundus and antrum samples. Compared with controls, Long-COVID-19 patients exhibited a significant reduction in mucosal innervation density: 2.1 vs 3.9 nm/µm³ (p<0.01) in the fundus and 1.9 vs 3.9 nm/µm³ (p<0.05) in the antrum. The reduction incholinergic innervation was more pronounced in the fundus (p<0.01) and also evident in the antrum (p=0.01). Gastric nerve density correlated with HRV parameters (LF/HF ratio: R=0.50, p<0.05) and NT-proBNP levels (R=0.52, p<0.01).