Doctor density varies by specialty and location. The United States has 15 practicing allergy & clinical immunologists. Broken out by state, allergy & clinical immunology doctor density in Alabama is 3, in California is 5, in District of Columbia is 2, in Florida is 2, in Hawaii is 1, in Illinois is 1, in Iowa is 1, in Louisiana is 2, in New Jersey is 2, in New York is 4, in Oregon is 1, in Pennsylvania is 2, in Tennessee is 1, and in Texas is 2.