ATLANTA -- It's the season for state and county fairs, and health officials are reminding fairgoers to be careful around pigs because of a new flu spreading from the animals to people.

Officials say 29 human cases of the new strain of swine flu have been confirmed in the last year, including 12 this week. Ten were linked to the Butler County Fair in southwest Ohio, which ended last weekend.

The new flu has a gene from the 2009 pandemic strain that might make it more contagious. But so far, the strain hasn't spread easily among people, and recent cases have been mild.

Fairgoers should wash their hands and avoid taking food and drinks into barns. Pregnant women, young children, the elderly, and people with weak immune systems should be extra careful.