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Last Updated

11 Jun 2003

Source: Wall Street Journal,  November 29, 2001.


U.S. Believes Lab Contamination Was Source of Anthrax in Chile


Federal health officials said that laboratory contamination appears responsible for the mysterious positive anthrax test of a letter sent to a Chilean pediatrician, leaving the fatal cases of two women in New York City and Oxford, Conn., as the most recent suspected to be bioterrorism.

The disclosure came as postal authorities in New Jersey announced they will begin delivering irradiated mail from the anthrax-tainted post office in Trenton, N.J., after sealing the mail in plastic bags and attaching handwritten notes attesting the mail has been cleaned using radiation.

And Federal Bureau of Investigation officials said that in a new effort to solve the anthrax case, they are sending in a special team of investigators to use outside-the-box thinking to re-examine clues that might have been overlooked.

The idea of enclosing the Trenton mail in plastic bags was recommended by a group of experts that included the Food and Drug Administration and the Department of Agriculture. Delivery of the 800,000 pieces of sanitized mail, destined for ZIP codes beginning with 085 and 086, will begin Saturday and take at least three weeks.

"The customers can decide for themselves how they wish to handle" the mail, said Vito J. Cetta, a postal official.

Officials with the Centers for Disease Control and Prevention in Atlanta analyzed the strain of the Chilean letter, sent by a private mail service from a medical publisher in Orlando, Fla., and concluded that it was different from the anthrax that has killed five people in the U.S. and "similar to strains outside the U.S.," said Mitchell Cohen, director of the CDC's division of bacterial and mycotic diseases.

Dr. Cohen said that when the Chilean scientists tried to culture anthrax from the envelope, "only a few colonies grew on the culture plate. If you were dealing with large concentrations of organisms, you would expect to get your plate covered with microorganisms."

By contrast, the "light culture growth" obtained in the Chilean lab "is more consistent with contamination from a laboratory source." He said that the CDC is working with the Chilean lab, which will send to the CDC other samples of anthrax it had in its possession. The CDC will then determine if they are the same. The anthrax strain also occurs in nature, Dr. Cohen said.

In a brief statement, Chile's Health Ministry said the CDC had confirmed there was anthrax on the envelope but that it was different from the anthrax used in the U.S. bioterrorism attacks. The statement did not address the issue of possible lab contamination in Chile.

-- Jose de Cordoba, Maureen Tkacik and Gary Fields contributed to this article.