Dengue infection carries increased odds of subsequent neurologic events

Acute dengue virus (DENV) infection appears to be associated with an increased likelihood of new-onset neurologic events, although the overall increase appears modest, according to a retrospective study from Singapore.

At 30 days following DENV infection, the odds of any new-incident neurologic events were up by more than ninefold (adjusted odds ratio [aOR], 9.69, 95 percent confidence interval [CI], 6.59–14.90). There were also elevations in the odds of memory loss (aOR, 3.19, 95 percent CI, 1.36–8.69), movement disorders (aOR, 7.10, 95 percent CI, 2.49–29.18), and other neurological events (aOR, 14.32, 95 percent CI, 8.61–26.04). [JAMA Neurol 2025;doi:10.1001/jamaneurol.2025.4608]

Similar findings were observed at the 60- and 90-day follow-up.

“However, the overall excess burden was modest, with less than 1 excess event per 100 cases,” the investigators noted.

In subgroup analyses, DENV-infected individuals had greater odds of memory loss and movement disorders compared with uninfected individuals, specifically among those aged ≥60 years (memory loss: aOR, 2.99, 95 percent CI, 1.30–7.87; movement disorders: aOR, 6.38, 95 percent CI, 2.23–25.96) and during DENV serotype 3 transmission (memory loss: aOR, 3.32, 95 percent CI, 1.34–9.76; movement disorders: aOR, 5.13, 95 percent CI, 1.71–21.88).

“Neurological manifestations in DENV infection can be attributed to various pathophysiological mechanisms, including direct viral invasion, systemic complications of acute infection, and postinfectious autoimmune syndromes,” the investigators said. [Lancet Neurol 2013;12:906-919; Curr Opin Infect Dis 2025;38:364-371]

DENV’s neurotropic potential has been previously documented, with the detection of DENV antigen in brain tissue and concurrent viral amplification in cerebrospinal fluid among DENV-infected patients presenting with encephalitis or encephalopathy during acute illness. [Lancet Neurol 2013;12:906-919; Clin Infect Dis 2024;79:498-501]

“Our results suggest that beyond encephalitis or encephalopathy, evidence exists for a broader spectrum of neurological events in the acute phase of DENV infection. Risk for a much wider spectrum of acute neurological complications, however, needs to be contextualized in the setting of low overall incidence, with less than 1 percent of DENV-infected cases associated with a concurrent acute neurological event,” according to the investigators.

Nevertheless, they emphasized that older adults be monitored for a wider spectrum of potential neurological complications following DENV infection.

For the study, the investigators used data from national registries to establish a cohort of 65,207 adults (mean age 48.4 years, 53.5 percent male) infected with DENV from 2017 through 2023 and a cohort of 1,616,865 uninfected population-based comparators (mean age 54.8 years, 45.2 percent male). Those infected with SARS-CoV-2 within 30 days of T0 were excluded, as were uninfected comparators with no prior healthcare contact.