Toddler dies after flu triggers rare encephalitis; parents urge awareness of symptoms

Lorelei Cowmeadow, a lively toddler from Wokingham, died three days after developing encephalitis that doctors say was triggered by influenza, her parents have told reporters. The two-year-old’s condition deteriorated from mild cold-like symptoms to life-threatening brain inflammation within hours, and she died on November 21, 2024 while in hospital.

According to her parents, Jack and Antonia, Lorelei was well enough to attend nursery and was dancing at home on the evening she fell ill. She woke in the night complaining for a bottle, then began to have seizures. Emergency services took her first to the Royal Berkshire Hospital in Reading, where staff induced a coma and ran tests, before transferring her to the John Radcliffe Hospital in Oxford for specialist care. Doctors told the family that an MRI and other tests showed influenza had caused encephalitis and that her brain had swollen and suffered irreversible damage. She died three days later, days before her second birthday.

Encephalitis is inflammation of the brain that can be caused by a direct infection of the central nervous system or by an immune response that mistakenly attacks brain tissue. Infectious causes most commonly include herpes simplex and varicella zoster viruses; influenza and measles can also cause encephalitis, though less frequently. Experts say the condition carries significant risks: around 6,000 cases occur in the United Kingdom each year, and between 10 and 20 percent of cases are fatal. Survivors may face long-term problems including memory loss, language and cognitive difficulties, fatigue and epilepsy.

“Any virus has the potential to trigger encephalitis — but not everyone who is infected with these viruses will develop it,” said Dr. Ava Easton, a senior research fellow in encephalitis at the University of Liverpool and chief executive of Encephalitis International. Professor Benedict Michael, chair of infection neuroscience at the University of Liverpool, said younger children and older adults are at higher risk because of less robust immune responses.

Doctors treating suspected encephalitis use a combination of clinical assessment and tests. A lumbar puncture to analyse cerebrospinal fluid, MRI brain scans and blood tests are typically used to confirm inflammation and look for specific viral causes. Treatment depends on the cause: antivirals such as aciclovir are effective against herpes simplex and varicella zoster and can markedly improve survival when given early, while autoimmune forms are treated with immunosuppressive therapies such as corticosteroids. Supportive care, including seizure control and measures to reduce brain swelling, is also critical.

Professor Michael cautioned that there is often a brief window in which treatment is most effective. “In most cases, there is a window of opportunity where early intervention improves survival,” he said. Aciclovir, he added, can give an 80 to 90 percent chance of survival for herpes encephalitis if administered within the first 24 hours. He and other experts emphasised that many viral causes of encephalitis lack specific antiviral drugs, so much of early care focuses on rapid recognition and symptomatic treatment.

Symptoms can begin subtly and mimic common illnesses, which contributes to delayed diagnosis. Early signs may include fever, headache, light sensitivity, nausea and vomiting. More severe or progressing signs can include confusion, changes in behaviour, difficulty speaking or moving, weakness in the arms or legs, seizures, drowsiness and, in some autoimmune cases, psychosis or hallucinations. Professor Michael noted that a key warning sign is behaviour that is markedly different from a person’s normal state and urged caregivers and clinicians to act quickly if they have concerns.

Public awareness of encephalitis is limited. A 2021 YouGov survey cited by specialists found that 77 percent of the UK public did not know what encephalitis was. Dr. Easton said this lack of recognition can lead to missed opportunities for early treatment, and she called for greater awareness among general practitioners, emergency department staff and the public, on par with campaigns for meningitis and sepsis.

Lorelei’s parents said clinicians treated her with antiviral medication and steroids, but the illness progressed too quickly to save her. Family and friends were able to say goodbye in hospital. In the wake of their loss, the couple decided to donate Lorelei’s kidneys; they later learned the organs were transplanted successfully into a 40-year-old recipient.

“We want some good to come out of this tragedy,” Jack Cowmeadow said. Antonia added that the family wants others to recognise the potential severity of what can begin as a mild viral illness. Medical experts reiterated that while encephalitis remains rare, prompt medical attention for concerning neurological or behavioural changes can be lifesaving.

Clinicians say that while it is not possible to prevent all cases of encephalitis, vaccination against preventable viral illnesses, early medical evaluation of neurological symptoms and rapid hospital assessment when behaviour or consciousness changes are crucial steps. When encephalitis is suspected, hospitals aim to begin appropriate antiviral therapy and supportive measures as quickly as possible while investigations are underway to determine the underlying cause.