Two more animals have succumbed to a Shigella infection at the Jacksonville Zoo and Gardens.
The deaths of brother bonobos Jumanji and Jenga comes just four days after Bulera, a 35-year-old western lowland gorilla, died from the infection, zoo officials said.
Jumanji was born in 1996 at San Diego Zoo Safari Park and moved to the Jacksonville Zoo in 2008 with his parents and sister. Jenga was born in 2011 at the zoo.
Shigella is a bacteria that mainly affects the intestines, causing symptoms like diarrhea, vomiting, cramps and dehydration. Apes may have a harder time fighting off the bacteria.
Zoo officials do not know the exact source of the bacteria, saying it may have come from an asymptomatic ape or, though unlikely, a staff member.
Zoo staff are helping other apes recover from the infection and say they have seen significant progress, officials said.