Authorities are crediting a young man with alerting the victims about the toxic fumes that were discovered in the home in the 1100-block of Bowles Road.. Fire officials say, if that young man hadn't called 911 when he did, they could be dealing with four fatalities.
Three of those victims, members of the same family, were released from the hospital Monday. A 12-year-old daughter remained hospitalized as of Monday afternoon.
The Antioch Fire Department says they are one lucky family.
It was close to being a very different situation. Paramedics rushed to the Antioch lakeside home where a family of four and their dog were all found unconscious.
The discovery was made by a male friend of the family's 18-year-old daughter. He arrived at the house just before 6 a.m. to pick her up.
"He had spoken with her earlier. It's our information that he had spoken with her earlier, and that she was complaining that she was very sick to her stomach," said Antioch Fire Chief John Nixon.
After no one answered the door, the young man looked inside the living room window and saw his friend's father passed out. The man immediately called 911 from his cell phone.
"My girlfriend's dad is passed out on the floor," the young man said in 911 audio released by police. "It looks like he puked on the floor, I don't know. I'm at the front door. I can't get in the house."
The Antioch fire chief says the call was made just in time because all the family members were close to dying from carbon monoxide poisoning.
"We were able to determine there over 600 parts per million of CO in the house," Nixon said. "CO becomes dangerous at 35 parts per million. At 100 parts per million it could be fatal. They had six times that."
The fire department says the source of the carbon monoxide poisoning came from a boiler. Until it is fixed, the Village of Antioch placed a red "Do Not Occupy" sign on the home's door.
It is likely the family had idea they were being poisoned.
"It does mimic the flu slightly," said Nixon. "However, because carbon monoxide is colorless and odorless, it's unlikely that they knew exactly what was happening until it was too late, and they passed out."
The house did not have a carbon monoxide detector.