State health officials say another case of a new swine flu strain has been linked 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.
Assistant State Epidemiologist Richard Danila said that gene could make this virus easier to spread to humans, so federal and state health officials including the Centers for Disease Control will watch it closely.
"It's not been seen in any other state yet, but we'll definitely be keeping an eye on it," Danila said.
All four people who have contracted the virus so far were exhibitors or family members of exhibitors who spent prolonged periods of time with pigs at the fair, Danila said. He suspects new cases at this point will be limited.
"The numbers of calls ... are way down," Danila said. "We got one or two calls over the weekend. So we're coming close I think that we can close out that chapter soon."
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.