Your medical data is not as safe as you think. Discover how a massive ransomware attack exposed millions and the key steps to protect your privacy now.

The new estimate nearly doubles the company’s previous report of 100 million affected individuals, already the largest healthcare data breach ever reported to federal regulators.

UnitedHealth Group says the impact from the cyberattack last year at its Change Healthcare subsidiary is much wider than previously understood, affecting

About 190 million Americans may have been affected by a cyberattack targeting UnitedHealth‘s subsidiary, Change Healthcare. The breach, which disrupted the company’s IT systems, resulted in the compromise of sensitive personal and medical information.

UnitedHealthcare now estimates that 190 million people were impacted as a result of the cyberattack on its Change Healthcare unit last February— almost double previous estimates.

A cyberattack on UnitedHealth Group Inc. that paralyzed the US health-care system last year, snarling billions of dollars in payments for doctors and hospitals, also exposed sensitive data from 190 million Americans.

Large-scale attacks on health providers expose the data of millions of Americans each year. Consumers must remain vigilant, experts say.