Ten more people have died from the West Nile virus this year, bringing the total to 64, the Centers for Disease Control and Prevention reported.

Four of the most recently reported deaths were in Michigan and three were in Illinois. Mississippi, Missouri and Nebraska had one death each.

Those figures don't include two deaths in Massachusetts and one in Pennsylvania reported by state health officials Friday.

The CDC on Friday reported 1,438 cases of West Nile infection in 30 states and the District of Columbia.

The virus causes flu-like symptoms and sometimes swelling of the brain, although most people bitten by an infected bug never get sick. The virus is most dangerous for the elderly and people with weak immune systems.

West Nile is common in Africa and the Middle East, but didn't appear in North America until 1999 in New York. The virus this summer spread to the West Coast, with one case in California.