Caution and fear have prompted some nations to monitor flights from India and others to ban Indian travelers as the plague epidemic there goes on.
The official death toll has risen to 54 in the port city of Surat, where the epidemic first was reported Sept. 20.
Since then, plague cases have spread to New Delhi and other areas; 47 cases were reported Thursday in the capital's Infectious Diseases Hospital.
"The million-dollar question now is, will all these people from Surat spread the disease throughout India," says Dr. N.K. Shah, World Health Organization representative in India.
The organization said Thursday that the killer plague was expected to be over within three weeks.
The Delhi government ordered all schools and movie theaters in the capital to close.
Most western airlines are monitoring passengers arriving from India. Germany's Lufthansa Airline has doctors on all flights from Frankfurt to New Delhi and Bombay, says Jim Freeman, an airline spokesman.
Delta, which connects to India via Frankfurt, says passengers are being monitored by crew. Flight 107 arriving at John F. Kennedy International Airport from Frankfurt on Wednesday was detained after a passenger who had started her trip in Bombay suffered nausea.
"We notified the health authorities and they confirmed it was strictly air sickness," says Bill Barry, a Delta spokesman.
British Airways is "being vigilant with passengers," says spokeswoman Marge Vodopia.
Saudi Arabia, the United Arab Emirates, Kuwait, Oman, Qatar and Bahrain banned flights to and from India.
