ST. PAUL -- Health officials have linked another case of a new swine flu strain to the Minnesota State Fair.

The Minnesota Department of Health says a teenage boy who had exhibited a pig during the fair developed a flu-like illness after he returned home. The boy later tested positive for a variant strain of H1N2.

The new flu strain contains a piece of the gene from the human pandemic virus that circulated globally in 2009.

Minnesota Public Radio News reports that all four people who have contracted the virus so far were exhibitors or family members of exhibitors who spent time with pigs at the fair.

Minnesota's new flu strain is different from another swine flu linked to farms and fairs that has sickened nearly 300 people in the U.S.