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Researchers Identify New Activation Pathway for Brain-Destroying Virus That Infects Up to 90 Per Cent of Adults

The JC virus lurks silently in most people but can destroy the brain if activated, and a newly discovered trigger affects 10 per cent of the population

Zotpaper••3 min read
Researchers have identified a previously unknown activation pathway for the human polyomavirus 2, commonly known as the JC virus, which is estimated to silently infect 50 to 90 per cent of adults worldwide. When activated, the virus destroys brain tissue — and the newly discovered trigger could affect up to 10 per cent of adults globally.

The JC virus, named after the patient from whom it was first isolated in 1971, spreads via the fecal-oral route and typically infects people early in life. Blood testing surveys have suggested that the vast majority of adults carry the virus, though initial infection is entirely asymptomatic.

Researchers hypothesise that the virus first infects the tonsils or gastrointestinal tract, where it establishes a persistent but silent lifelong infection in what is called its archetype form. The virus only becomes dangerous if it mutates into a neurotropic form capable of crossing into the brain.

Previously, activation was primarily associated with severe immunosuppression — particularly in HIV/AIDS patients or those on certain immunosuppressive medications. The new research, published this week, suggests an additional activation mechanism that could put a much larger segment of the population at risk.

When the JC virus does activate and reach the brain, it causes progressive multifocal leukoencephalopathy, a devastating condition that destroys the myelin sheath protecting nerve fibres. The disease is often fatal and has no established cure.

Analysis

Why This Matters

The discovery of a new activation pathway for an incredibly common virus could reshape how doctors assess risk for neurological disease, particularly in patients who are not traditionally considered immunocompromised.

Background

The JC virus has been known since 1971 but received limited public attention because activation was considered rare and confined to severely immunosuppressed individuals. The new findings widen the at-risk population considerably.

Key Perspectives

Neurologists and infectious disease specialists are calling for expanded screening and monitoring protocols. However, some caution that the activation risk, while broader than previously thought, remains relatively low for any individual.

What to Watch

Further research into the specific mechanism of the new activation pathway, and whether therapeutic interventions can prevent the virus from reaching the brain once activated.

Sources