SIOUX FALLS, S.D. (AP) — Health officials in the Dakotas say they're seeing cases of H1N1 flu — the same strain that caused a pandemic four years ago.

The virus has caused two deaths in South Dakota. In the 2009-10 flu season it killed 24 people in the state.

State Epidemiologist Lon Kightlinger tells the Argus Leader the virus is back and circulating around the country. He says the best protection is a flu shot. This year's influenza vaccine protects against the H1N1 strain, and supplies are good.

There have been no H1N1 deaths reported in North Dakota, where about half of the 23 cases are in Ward County. First District Health Unit nurse Danell Eklund tells KXMC-TV it's hard to say why. She also urges people to get a flu shot.

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