A strain of the Killer Flu Virus may have been accidentally unleashed upon the public last fall.

But health officials say it appears no one was hurt and you have nothing to worry about.

The strain of the 1957 Asian Flu bug was sent to 3,700 laboratories across the world as part of a routine testing procedure.

That strain killed 1 million people worldwide in 1957.

The company that mailed out the virus did not now how deadly it was. The labs were supposed to test the virus and then destroy it.

Labs everywhere, including 64 in Wisconsin, started receiving the strain last fall.

"A health expert says the virus did not get out into the community, or else they would have known about it. We would have known already because it would have made people extremely ill and the likelihood that they would be tested would be very high," said Dr. Kathryn Vedder of the Wisconsin Department of Public Health.

It took so long to find out about the Killer Flu being sent out because most labs only tested it to see what kind of strain it was.

It wasn't identified as the Asian Killer Flu until a Canadian lab did a more thorough exam on the virus.