Lincoln Park Zoo officials are watching six ailing, quarantined chimpanzees around the clock after an adolescent member of the group died in the zoo's hospital earlier this week.
The 9-year-old chimp, a male named Kipper, died Tuesday, a day after veterinarians brought him to the zoo hospital. He and the other six members of his group, who are usually on exhibit in the Regenstein Center for African Apes, came down with a mysterious upper respiratory infection March 19.
The cause of the respiratory ailment is still unknown, and there is no indication that it has spread to the ape house's other chimp group or to its two gorilla families, said Steve Thompson, the zoo's vice president of conservation programs.
The initial necropsy reports listed pneumonia as the cause of Kipper's death, according to Thompson. The youngest member of his group, Kipper had a congenital condition that may have limited his breathing capacity, causing more serious problems for him than for the others, Thompson said.
Great apes like chimpanzees and gorillas suffer from the same sorts of respiratory diseases as humans, so zoos have been instituting increasingly more rigid protocols to limit direct contact between humans and apes. Even on a normal day at Lincoln Park Zoo, any human coming into contact with the apes is required to wear sterile masks, clothing and footwear.
It's possible the apes could contract disease from wild animals that occasionally get into their outdoor habitats, such as squirrels and birds, Thompson said, adding that it may be impossible to learn how the chimpanzees were infected.
With the initial symptoms in the chimpanzee group persisting over the weekend, the zoo took the seven chimps off display and put them in quarantine quarters in the lower level of the ape house.
The facility has no true isolation ward, but ill and healthy animals are kept on opposite sides of the building and keepers do a complete clothing change when moving between groups.