The CDC is investigating an outbreak of a bacterial infection linked to puppies sold through the national pet store chain Petland.The outbreak of Campylobacter infections has sickened 39 people from seven states, including Florida, Kansas, Missouri, Ohio, Pennsylvania, Tennessee, and Wisconsin.So far nine people have been hospitalized. No deaths have been reported.Campylobacter can cause a gastrointestinal illness in humans with symptoms of diarrhea, cramping, abdominal pain, vomiting, and fever. The illness typically lasts about a week and symptoms appear within two to five days after exposure. People more likely to get a severe infection include children younger than 5, adults older than 65, pregnant women, and people with weakened immune systems, including those with the genetic blood disorder thalassemia or HIV or people receiving chemotherapy.Investigators say evidence indicates that puppies sold through Petland stores are a likely source of this current outbreak. The bacteria can spread through contact with dog feces. It usually does not spread from one person to another.Twelve of those affected are Petland employees from four states. The other 27 people either recently purchased a puppy at Petland, visited a Petland store, or visited or live in a home with a puppy sold through Petland before illness began.The CDC says the pet store chain is cooperating with health officials to address the outbreak.  CBS 58 