From ANIMAL PEOPLE, December 2005:

Some U.S. animal studies are considered too risky to send
abroad–like the biological defense studies to be done at the $167
million Galveston National Laboratory at the University of Texas
Medical Branch, scheduled to open in 2008.
Such facilities are designed to be ultra-secure, but have had lapses.
New York City attorney Michael C. Carroll argued in his 2004 book Lab
257 – The Disturbing Story of the Government’s Secret Plum Island
Germ Laboratory that research accidents may have introduced Lyme
disease and West Nile fever to the U.S.
Whether or not that happened, three lab mice who were
infected with deadly strains of plague as part of a federal
biodefense project disappeared in early September from separate cages
at the University of Medicine & Dentistry of New Jersey. The loss
was disclosed two weeks later by Josh Margolin and Ted Sherman of the
Newark Star-Ledger.
In January 2005 Boston University was embarrassed by the
disclosure that two researchers were infected by a potential lethal
form of the rabbit-borne disease tularemia in May 2004, and another
in September. Their illnesses were not identified until October.
Boston University reported the cases to city, state, and
federal health agencies, as required, but they were not revealed to
the public until after November 2004 hearings on university plans to
build a “Biosafety Level 4” high-security lab at its South End
medical campus, located amid a densely-populated urban neighborhood.