US health officials warned Tuesday that passengers on two international flights may have been exposed to an extensively drug-resistant strain of tuberculoWashington (eCanadaNow) - US health officials warned Tuesday that passengers on two international flights may have been exposed to an extensively drug-resistant strain of tuberculosis.

The US Centres for Disease Control (CDC) said a US citizen infected with the lung disease travelled on an Air France flight from Atlanta, Georgia to Paris on May 12 and then on a Czech Air flight from Prague to Montreal on May 24.

The CDC said the passenger has been identified and been quarantined through a rare federal order signed by President George W Bush. The federal government has the authority to quarantine people suffering from eight specific diseases, but has not done so for more than 40 years, CNN reported.

CDC Director Julie Gerberding said at a televised press conference that the patient would remain in isolation until he was no longer infectious.

Passengers sitting near the infected passenger and crew members were urged to be tested for the disease.