A patient in Missouri has tested positive for H5 bird flu, but unlike previous cases there is no known link to animals, according to state and federal officials. The source of the infection is still unknown. The patient, who was only described as an adult with underlying medical conditions, was hospitalized on August 22. After testing positive for Influenza A, a specimen was sent to the state lab for additional testing, which revealed the H5 subtype. “The specimen was forwarded to CDC for additional testing and was confirmed as H5 subtype of flu, also known as a bird flu, or avian flu. Additio…