Hospital burden and clinical features associated with admission among confirmed measles cases during the 2025-2026 outbreak at a tertiary care hospital in Mexico.

OBJECTIVES: Measles has re-emerged as a public health concern despite effective vaccination. This study describes the clinical and epidemiological characteristics associated with hospital admission among confirmed measles cases attended at a tertiary referral hospital in Jalisco, Mexico, during the 2025-2026 outbreak. METHODS: We conducted an observational, hospital-based cohort study of confirmed measles cases attended from November 2025 to May 2026. Congenital measles cases and records with missing hospitalization status were excluded. Data were obtained from clinical records and surveillance systems. Univariable logistic regression and two multivariable models were fitted: an epidemiological model excluding respiratory severity markers and a clinical presentation model including oxygen saturation and respiratory rate. RESULTS: Among 609 confirmed cases, 186/609 patients (30.5%) were hospitalized. Most were pediatric patients (460/609 [75.5%]), and 489/609 (80.3%) were eligible but unvaccinated. Among hospitalized patients, pneumonia was the most frequent complication (51/186 [27.4%]), and 107/186 (57.5%) required supplemental oxygen. In the epidemiological model, each additional day from symptom onset to medical care was associated with hospitalization (adjusted odds ratio [aOR] 1.14 per day; 95% confidence interval [CI] 1.04-1.25), lower oxygen saturation (aOR 3.51 per 5-percentage-point decrease; 95% CI 2.53-4.98), and higher respiratory rate (aOR 1.27 per 5 breaths/min increase; 95% CI 1.05-1.54). CONCLUSION: Hospital admission was common and was mainly characterized by delayed care and objective respiratory compromise.