"Bird Flu" is a Dance/Gaana/Hip hop song recorded by the Sri Lankan Tamil rapper and singer M.I.A.. It was released as a downloadable single on iTunes on November 23 2006, despite M.I.A. not considering this song to be the album's first official single. It was first mentioned in M.I.A.'s MySpace blog on August 18, 2006. Inside the post she talked about how she shot a music video for the song in a fishing village on the south coast of India. She also said that she called the song "Bird Flu" as "this beat gon [sic] kill everyone!!" M.I.A. finally posted the video for this track on her MySpace in early February 2007. M.I.A. also talked about the filming location for Bird Flu and how it had a personal connection for her:

M.I.A. also mentioned in the same interview that Paulina, the girl featured a lot in Bird Flu, was not specifically picked for her role; she just happened to be playing outside when they were recording the song (and they could not keep her out of their studio).

"Bird Flu" incorporates elements of the song "Thirvizha Na Vantha" from the Tamil film Jayam. "Bird Flu" utilises the gaana genre (Dappan koothu music). Arulpragasam recorded the song using live urmi drummers from temples in Chennai, Tamil Nadu.

A remix of "Bird Flu" by Cavemen was made available as a bonus track on the Best Buy edition of the album Kala. This Song will featured in FIFA Street 3.