About 85 U.S. Marines-in-training remained ill last week after an apparent shiga-toxin producing E. coli outbreak at Marine Corps Recruit Depot San Diego and Camp Pendleton amid a week-old outbreak of diarrheal illnesses at the military installations, authorities reported.

Among the medical cases were 19 new ones diagnosed since Oct. 31, 2017, according to MCRD public affairs. In all, 16 recruits were receiving treatment at an off-base hospital, with the remainder being cared for at military medical facilities.

Base officials initially announced a total of about 300 cases of intestinal ailments at the 2 San Diego-area installations on Oct. 30, 2017.

 That tally was down to roughly 215 a day later. The cause or causes of the debilitating bacterial exposure remain under investigation.