Vietnam has asked for help from the World Health Organization on Friday to investigate a mysterious illness that has already killed 19 people and caused 171 others to fall ill.

According to the BBC, the first instances of the illness were reported between April and December 2011 and then subsided until now.

The cases have been reported in an impoverished central province of Vietnam called Quang Ngai.

The Vietnamese health ministry sent a team of investigators to the area earlier in the month, but they were unable to determine the cause of the illness, said Bloomberg.

The government has now asked the WHO and US Centers for Disease Control and Prevention to help determine the cause of the illness.

According to RT, the symptoms of the disease include blistering on hands, feet and mouths accompanied by high fever and eventual organ failure or liver complications.

The disease has so far infected mostly children and babies.

Officials have been slow to report a mounting death toll as the cause of the disease is still not known.

"We know about the deaths, but because we were yet to identify their causes, we did not report them for fear of scaring local people," said Dang Thi Phuong, director of Ba To's health center told UPI.

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