Despite estimates that more than one billion people will be affected by Alzheimer’s disease by 2050, many around the world still don’t understand the disease.

In a survey of more than 6000 people from 12 countries, the Alzheimer’s Association says nearly a quarter of responders list Alzheimer’s disease as the condition they most fear getting, behind cancer. Yet in some countries, including India, China and Saudi Arabia, more than 80% believe that the neurodegenerative condition is a normal part of aging, and not an abnormal state of the brain in which plaques of proteins build up and break down nerve connections. At the same time, nearly 40% of people believed that only those with a family history of the disease could be affected.

And while the disease is often associated with symptoms of memory loss and cognitive decline, it can eventually affect physical functions as well and be fatal in those affected. “Alzheimer’s disease knows no bounds,” Harry Johns, president and CEO of the Alzheimer’s Association said in a written statement about the survey. “Anyone with a brain is at risk for Alzheimer’s disease, so everyone with a brain should join the fight against it.”

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