Contagious diseases of air passengers not reported

Hundreds of people at major U.S. airports each year are severely ill with symptoms of potentially contagious diseases, yet few are reported to health officials as intended under U.S. regulations and international guidelines, a USA TODAY review of ambulance records and federal data shows.
To detect diseases such as pandemic flu, tuberculosis and measles, federal regulations require airlines to notify health officials of passenger illnesses involving diarrhea or fever plus rash, swollen glands or jaundice. The International Civil Aviation Organization, a United Nations agency, also includes persistent vomiting or coughing in its guidelines.
Concerns about fliers spreading dangerous diseases have been fueled by the 2003 SARS outbreak, high-profile tuberculosis patients and the H1N1 flu pandemic.
http://www.usatoday.com/news/health/2010-04-21-sick-passengers_N.htm