6 chimps in quarantine at Lincoln Park Zoo

Keepers at the Lincoln Park Zoo had six ailing chimpanzees in quarantine and under close observation Thursday after the recent death of another chimp from a mysterious respiratory illness.

Kipper, a 9-year-old and the youngest member of a group headed by a male chimp named Hank, died Tuesday in the zoo hospital, where he had been taken a day earlier. Zoo spokeswoman Sharon Dewar said Kipper and the others six developed flu-like symptoms last week.

"We are guessing it's a virus, but we don't really know exactly what it is," Dewar said Thursday.

Because the illness appears contagious, the surviving six chimps were being kept in isolation from all other chimps and gorillas that live in the zoo's Regenstein Center for African Apes. The affected group is the chimp family normally on public view at the ape house.

A necropsy performed on Kipper after he died indicated the cause of death as pneumonia, according to Steve Thompson, the zoo's vice president of conservation programs.

Great apes like chimpanzees and gorillas suffer the same types respiratory diseases as humans, Thompson said.

On Thursday keepers reported the members of Hank's group showed signs of runny noses and listlessness.

As the symptoms persisted over the weekend, zoo officers took Hank's group off display and put them in quarantine quarters in the ape house lower level.

After going into isolation with the rest of the group, Kipper, who suffered from a congenital condition that may have decreased the pumping capacity of his lungs, on Monday took a turn for the worse, Thompson said.