WASHINGTON - A total of 19 flu-associated child deaths have been reported and more than 3,500 have been hospitalized for influenza this winter in the United States.

The U.S. Centers for Disease Control and Prevention (CDC) announced Friday that in the week ending last Saturday, 3.1 percent of people saw doctors for flu-like illness, above the national baseline of 2.2 percent.

Three more kids were reported to die of influenza during that week. Two were associated with influenza A pdm09 virus, the most frequently identified influenza virus type this year. Another one associated with influenza a virus for which no subtyping was performed, according to CDC.

Nearly 99 percent of 752 influenza-positive tests reported to CDC were influenza A viruses, among which nearly 90 percent were H1N1 pdm09 viruses.

The World Health Organization (WHO) reported on Jan. 7 an increase of influenza activity across the Northern Hemisphere, with the H1N1 strain dominating in North America and Eastern Asia.

The proportion of deaths attributed to pneumonia and influenza in the United States was 6.9 percent during the week ending Jan. 5, which was below the epidemic threshold of 7.0 percent at that time every year, according to CDC.