A woman covers her eyes in an undated photo. Fewer than half of Americans can recognize the top five warning signs of stroke, information that could help save thousands of people from death and disability, the CDC said on Thursday. REUTERS/File

CHICAGO (Reuters) - Fewer than half of Americans can recognize the top five warning signs of stroke, information that could help save thousands of people from death and disability, the U.S. Centers for Disease and Control and Prevention said on Thursday.

Their report uncovered significant disparities in awareness, with whites, women and people with higher levels of education much more likely to be aware of individual stroke warning symptoms and call for an ambulance than others.

“These findings indicate a need to increase awareness of stroke warning symptoms in the entire population, and particularly among blacks, Hispanics, men and persons at lower education levels,” the CDC said in its weekly report on death and disease.

Stroke warning signs include sudden numbness or weakness of the face, arm or leg, especially on one side; sudden confusion or difficulty speaking; sudden trouble walking, dizziness or loss of balance; sudden trouble with vision in one eye or both; and severe headache with no known cause.

To determine awareness of these warnings, the CDC in 2005 surveyed more than 71,000 people by telephone in 13 states and the District of Columbia.

They found that only 44 percent could identify all five stroke warning signs. Some 38 percent were aware of all stroke warnings symptoms and said they would call an ambulance first if they thought someone was having a stroke or heart attack.

Just 16 percent knew all of the stroke warning signs, knew that sudden chest pain was not a stroke warning sign and said they would call an ambulance if they thought someone was having a heart attack or stroke.

“Immediate emergency transportation to a hospital to receive timely urgent care can reduce disability and even death associated with stroke,” the CDC said.

Stroke is the No. 3 killer in the United States behind heart disease and cancer. The CDC estimates 780,000 Americans will have strokes this year. They will kill 150,000 people and leave 15 percent to 30 percent of survivors permanently disabled.