Discharge is not the finish line: Outcomes of childhood encephalitis in Australia

An important Australian study has found that the two main types of encephalitis (infectious and immune-mediated) affect children in different ways. It also shows that there can be after-effects of encephalitis that can surface after discharge from hospital.

Background

The research published last month by Rao et al., in The Lancet Regional Health – Western Pacific offers the clearest picture yet of what happens to children in the year after they are hospitalised with encephalitis (1).

The Australian Childhood Encephalitis (ACE) study tracked children under 15 across five paediatric hospitals between March 2014 and June 2018. Of 724 suspected cases, an expert panel confirmed 408 as genuine encephalitis.

Two very different conditions

One of the study’s most useful contributions is showing how sharply outcomes diverge by type of encephalitis.

Children with infectious encephalitis were younger and were more likely to present with more severe illness, with two-thirds requiring intensive care. The researchers note that, due to their younger age, neurological symptoms may be not recognised. In this study, children affected by parechovirus and herpes simplex virus were more severely affected than children with other types of infectious encephalitis.

Children with immune-mediated (autoimmune) encephalitis were older and required intensive care relatively less often. In these children, the after-effects improved over 12 months. The main types were acute disseminated encephalomyelitis (ADEM) accounting for 74% of cases, followed by anti-NMDAR encephalitis (19%).

This is important because the cause of a child’s encephalitis shapes what recovery looks like so families and clinicians should not expect the same follow-up needs.

What predicts long-term after-effects of encephalitis?

The researchers draw up a shortlist of early features that could influence and predict a more severe disease:

• Length of hospital stay
• Length of ICU stay
• Symptoms such as personality or behavioural changes
• Symptoms such as motor weaknesses
• MRI findings showing encephalitis

These predictors are important because such early-stage features can help to identify which children require closer follow-up after discharge.

The researchers found some possible warning signs, but more research with larger groups of children is needed to know if these signs can accurately predict long-term neurological problems after encephalitis.

Conclusion

This is one of the most comprehensive studies published to date on the long-term outcomes of encephalitis in children, covering both infectious and autoimmune types of encephalitis.

The practical takeaway is straightforward: unfortunately, discharge is not always the finish line. The authors argue for structured monitoring of at least 12 months for every child.

The researchers

The full list of researchers is: Gautam J. Rao, Russell C. Dale, Rebecca Burrell, Luis Furuya-Kanamorif, Katherine Phan, Christopher C. Blyth, Jim P. Buttery, Julia E. Clark, Nigel W. Crawford, Helen S. Marshall, Robert Booy, Cheryl A. Jones, and Philip N. Britton, on behalf of the Paediatric Active Enhanced Disease Surveillance (PAEDS) Network.

References

1. Rao GJ, Dale RC, Burrell R, et al. Long-term outcomes of childhood encephalitis in Australia: burden and predictors from the Australian childhood encephalitis (ACE) prospective multicentre cohort. Lancet Reg Health West Pac. 2026;73:101951. Published 2026 Aug 8. doi:10.1016/j.lanwpc.2026.101951
2. Fillâtre P, Mailles A, Stahl JP, et al. Functional outcome after infectious encephalitis: a longitudinal multicentre prospective cohort study. Clin Microbiol Infect. 2025;31(3):459-465. doi:10.1016/j.cmi.2024.11.001

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To view the original paper, click here.

For our information for children affected by encephalitis, click here.

For our factsheet on acute disseminated encephalomyelitis (ADEM) in children, click here.

For our factsheet on herpes simplex virus encephalitis, click here.