The World Health Organization has issued a list of symptoms that indicate an infection of pandemic H1N1 virus, commonly known as swine flu, is progressing toward complications such as pneumonia and medical attention is required.
Worrisome signs, the agency said, include shortness of breath, difficulty breathing, turning blue, bloody or colored sputum, chest pain, altered mental status, a high fever lasting more than three days, and low blood pressure.
In children, particular danger signs include fast or difficult breathing, lack of alertness, difficulty in waking up, and little or no desire to play.
Because the disease can progress very quickly once such signs appear, an immediate visit to the family doctor or to the emergency room is warranted, the WHO said.
As of Friday, according to the Centers for Disease Control and Prevention, there have been 5,314 swine-flu-related hospitalizations in 47 states and U.S. territories and 353 deaths.
-- Thomas H. Maugh II