Covance confirmed Thursday that five monkeys at its research laboratories in Madison were diagnosed with tuberculosis in June.
Thirty-two monkeys housed in the same room were euthanized to keep the illness from spreading, and additional monkeys that may have had "fleeting contact" with the infected animals were quarantined, Covance said.
It's the first case of tuberculosis among the company's Madison lab animals in 12 years, the company said in a written statement.
No Covance employee tested positive for the illness. "The public was never at risk at any time," the statement said.
"Monkeys are more likely to get tuberculosis from humans than the other way around," said Susan LaBelle, Covance vice president of global marketing, in Madison.
Covance, one of the world's largest drug testing companies, is one of Madison's largest employers, with about 1,300 employees. Its East Side campus, on Kinsman Boulevard near the Dane County Regional Airport, has undergone several big expansions in recent years.
Tuberculosis in monkeys housed in research labs was once fairly common but is now rare, said Dr. Taylor Bennett, Chicago, a veterinarian and associate vice chancellor for research at the University of Illinois-Chicago.
"Every once in a while, an institution will get a shipment of monkeys that has picked up tuberculosis somewhere," said Bennett, who is also a paid consultant for Covance.
Covance sent a letter to the state veterinarian about the problem on June 22, said spokeswoman Donna Gilson of the Wisconsin Department of Agriculture, Trade and Consumer Protection.
The company commented publicly on the monkey illness after a Chandler, Ariz., citizens group made the incident public. Citizens Against Covance member Michael Boerman said he obtained the documents from DATCP through a public records request.
"I think what bothers me the most is, No. 1, the fact that Covance didn't have the safeguards in place to prevent this kind of thing," said Boerman.
Citizens Against Covance is fighting the Princeton, N.J. company's effort to build laboratories in Chandler, a Phoenix suburb. Animal-rights activists also have staged protests against the plans.
Boerman said Covance did not say when or from where the monkeys were imported, according to the papers released to him. He also claimed Covance sold monkeys to other research organizations without telling them about the tuberculosis.
LaBelle said Covance maintains "precise" quarantine records that show how and when its research animals enter the country, and said monkeys from the company's Madison labs are not sold to other research organizations.
She had no immediate information about how many monkeys are housed in Covance's Madison labs or how many employees have contact with the animals. But she said the company has "rigorous standards and procedures designed around worker safety and animal health" that reflect standard practice in the industry and conform to Centers for Disease Control guidelines.