A 12-year-old from Tampin, Negri Sembilan, died after catching both dengue and leptospirosis, Sinar Harian reported.
Umar Abd Qayyum Yassir Arafat's father Yassir Arafat Mahat, 43, said his son had a high fever last Thursday after swimming at the Mount Tampin recreational park a week before.
"We brought him to Tampin Hospital and the doctor said he was okay. His body temperature went down after taking antibiotics," he said.
Yassir Arafat said Umar's body turned ice cold a day later, and he suffered from rapid dehydration and a stomach ache.
Umar died at Malacca Hospital on Monday morning after being transferred from Tampin Hospital the evening before.
According to Malacca Hospital director Datuk Dr Za'aba Baba, the cause of death was severe secondary dengue fever with bleeding shock and multiple organ failure.
"The patient has also tested positive for leptospirosis," he said.