One in 3 children in Puerto Rico has asthma, one of the highest rates of prevalence in the world. Experts are mystified whether it's due to genetics, the environment or both.
msnbc.com: Top msnbc.com headlines, NBC News
Mon, 12/27/2010 - 7:34am
One in 3 children in Puerto Rico has asthma, one of the highest rates of prevalence in the world. Experts are mystified whether it's due to genetics, the environment or both.