When Hu Haitao watched his son Hu Bing swallow the small white pills meant to protect him from polio, he never imagined what the end result would be.
14 days after taking the vaccine, the four-and-a-half-month-old was on life support.
"My baby experienced diarrhea and respiratory failure," said Hu. "He was critically ill and had to stay in the ICU."
What followed next is every parent' s worst nightmare.
Young Hu slipped into a coma and experienced heart failure.
After three days of treatment, the baby recovered, but his left leg was left paralyzed.
Staff at the hospital in Jinan, in the eastern Chinese province of Shandong said the baby was suffering from polio, but did not give a more specific explanation.
It is a story too close for comfort for mother Ma Yongmin.
Her daughter Zhang Liyang received the polio vaccine in December 2012. Nine days later, the six-year-old was also in hospital.
After taking the vaccine, the youngster complained about a pain in her back. Like most mums, at first Ma thought her daughter just did not want to go to school. But she kept complaining, so her father Zhang Gongxian took her to their local hospital.
"The doctor asked me if she had received any vaccinations, I told him "yes, she had a varicella vaccination," Zhang said. "The doctor told me that the vaccine can possibly lead to illness, but we didn't think it would become so bad."
Little Zhang then lost feeling below the waist.
Desperate for answers, her father took her to a major hospital, also in Jinan, where doctors diagnosed her with myelitis, or inflammation of the bone marrow in her spinal cord.
"She suffers from incontinence and her legs cannot feel any pain or temperature changes," Shi Jiming, the girl's physician said. "From a medical perspective, she is paralyzed from the waist down."
Once a happy six-year-old who loved dancing and singing, Zhang is now confined to her bed. Her days are spent watching cartoons. Sometimes her parents tie her to a makeshift rack so she can experience the sensation of standing.
Young Zhang has been receiving therapy for her condition, but is not expected to walk again.
Ma believes the varicella vaccination given to her daughter is the cause of her paralysis.
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