Trace amounts of anthrax could have contaminated tens of thousands of letters mailed across the country that passed through a tainted New Jersey postal facility, a top federal health official said Monday.
"There seems to be the potential for not just hundreds and not just thousands but tens of thousands and maybe more letters to be potentially at risk for some level of cross-contamination," said Dr. Jeffrey Koplan, director of the Centers for Disease Control and Prevention in Atlanta. He stressed that there was no proven danger.
The issue surfaced as officials tried to determine if there is a link between the deaths of a Connecticut woman and another in New York from inhalation anthrax and letters mailed through the contaminated facility.
Officials have tracked 300 letters that passed through a Hamilton, N.J., mail sorting machine within seconds of anthrax-laden letters mailed to Sens. Tom Daschle and Patrick J. Leahy on Oct. 9. They followed up on two of the letters--both mailed to addresses near the women's homes--but officials said Monday they had not decided whether to contact the recipients of any of the other letters they tracked.
Five people have died, three of them after exposure to anthrax-laden mail. Investigators are stymied by the deaths of Ottilie Lundgren, 94, of Oxford, Conn., and Kathy Nguyen, 61, of New York, who had no known exposure to such mail.
Health, law enforcement and postal investigators working in tandem have determined that a letter sent to a home a mile from Lundgren's that had been processed through New Jersey contained a single anthrax spore. Another letter that passed through the facility was sent to a South Bronx address near Nguyen's apartment, but officials at two businesses there had no recollection of receiving a letter from New Jersey.
Dan Mihalko, a federal postal inspector spokesman, said 35,000 letters an hour can pass through the type of sorting machine that processed the contaminated letters. He said a printout by bar code is kept of the address of every letter that goes through such a machine and of the time when it was processed.
Mihalko said "a decision has not been made" on whether to track down, to the point of delivery, several hundred other letters that would have gone through the machine at about the same time as the contaminated letters.
Health officials in every area of the country are on alert, but so far, Koplan said, no infections from such cross-contaminated mail have turned up. He and others stressed that there was no established risk from such trace amounts, and that "with each passing day, the lack of further cases occurring is grounds to diminish the risk from any one of these letters."
Traces of anthrax were also found on mail equipment at a Wallingford, Conn., postal facility, on the fourth round of testing. Officials said the latest testing was targeted rather than random, with postal employees giving input to CDC investigators who reached into nooks and crannies of specific machines through which cross-contaminated mail might have passed.
Federal and New York health officials said they did not know whether such targeted retesting would be done at New York postal facilities near Nguyen's apartment building, or at other facilities where cross-contaminated mail might have been processed.
Some officials said they were becoming more convinced that cross-contamination was a likely cause of at least Lundgren's death.
"We think that's the most likely way she got exposed, through the mail," Dr. James Hadler, epidemiologist for the Connecticut Department of Health told Associated Press. "She's most likely the victim of the letters that were introduced into the postal service on Oct. 9."
Health and Human Services Secretary Tommy G. Thompson said early Monday that he believed experts had found enough evidence to label the Nov. 21 death of Lundgren a case of cross-contamination. But by afternoon, in a joint telephone media briefing with the CDC's Koplan, he backtracked, saying such evidence was circumstantial. He said cross-contamination was "high on the list, but it's not the only thing we're looking at."