The Centers for Disease Control and Prevention last week proposed “the first significant changes in quarantine rules in 25 years” as part of the federal government’s effort to prepare for a possible flu pandemic or other contagious disease outbreak. It would require airlines and cruise lines to collect and electronically maintain detailed passenger information for at least 60 days in an effort slow the spread of contagious diseases such as the avian flu. Passengers would be requested to provide information - such as phone numbers, e-mail addresses and seat locations - which then would be transmitted to the CDC within 12 hours. The agency would destroy the information after a year because it no longer would be useful in tracing disease outbreaks. Dr. Martin Cetron, director of the CDC's division of global migration and quarantine, said the data would be kept confidential and would be used only for public health reasons. Passengers who refuse to provide data still would be able to travel, but Cetron said he expects most passengers to comply. The SARS outbreak in 2003 highlighted the need for new regulations. Public health officials had difficulty collecting data and tracing infected travelers because airlines often delete contact information from their computer systems within a day or two. Epidemiologists were forced to compile and process by hand available data from flight manifests, customs declarations and other sources. The cost of the new provisions would fall mostly on the travel industry, but exact estimates vary. Some reports claim that the new rule could cost airlines as much as $108 million annually and cruise lines as much as $800,000 annually. Others estimate that the data-gathering requirements could cost the airline and cruise industries as much as $395 million annually.