The woman's family is accusing the hospital of negligence and wrongful death.
They claimed she contracted Legionnaires' from another person housed on the same floor of the hospital, calling her death preventable.
"We had many plans, we had hobbies," said Gibran Ruiz through tears.
Ruiz is still mourning, recounting the life he and his wife Carol wanted before she died.
"I still wake up some days in complete disbelief that this happened," he said.
According to the Ruiz family attorney, 35-year-old Carol Ruiz was admitted to Northwestern Memorial Hospital on October 25, 2017, for a clinical trial to help patients with multiple sclerosis.
Her immune system was suppressed as part of the treatment.
Less than a month later, she was dead after contracting Legionnaires' disease.
"While Carol was a patient at Northwestern, she was exposed to contaminated water," said attorney Thomas R. Mulroy III of Salvi, Schostok & Prichard.
The victim's daughter, Melane Cosme, is also involved in the lawsuit.
"I'm a senior in college, and I wish she could have seen me graduate," Cosme said.
Attorney Thomas Mulroy said Ruiz Northwestern Hospital housed Ruiz – with a compromised immune system – on an improper floor.
Five months earlier, another person contracted Legionnaires. The Illinois Department of Public Health connected both cases late in 2017.
Northwestern Memorial Hospital declined to comment due to pending litigation.
According to an email from the Chicago Department of Public Health provided by Mulroy, Legionella bacteria were found in the sink of Ruiz's room at Northwestern Hospital. In the email, an official states water temperatures and copper ion levels were too low. Water temperatures and ion levels can help prevent Legionella bacteria from growing.
Gibran Ruiz said he wants answers.
"We'd like to know why, we'd like to know more about what actually happened and not silence, because it says nothing," Ruiz said.
The Illinois Department of Public Health is reporting a steady increase in Legionnaires' disease cases reported in the state over the past 10 years:
2018 = 509
2017 = 332
2016 = 318
2015 = 315
2014 = 249
2013 = 299
2012 = 226
2011 = 151
2010 = 149
2009 = 134
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