Five of six van passengers pass out, doctor blames carbon monoxide

On Sunday, five passengers in van that shuttled between Mukdanah and Yasothon were found unconsciousness in their seats, and some were vomiting when the van arrived at the Yasothon bus terminal at 3.45pm.

The driver and the passenger sitting in the front seat beside him did not suffer any symptoms.

Four of the five passengers were later admitted to Yasothon hospital.

When the van arrived at the terminal, taxi motorcyclists checked the passengers to inquire whether they would like to use their services, but none did, so the motorcyclists called for emergency health service.

The van driver, Somsak, 51, later told police that he thought the passengers simply took a nap during the ride and did not know that they were passing out.

Earlier, the Yasothon land transport office said it believed passengers had passed out because the air-conditioner broke down, resulting in heat and poor ventilation inside the van.

But Associate Professor Dr Weerasak Charaschaisri, a forensic-medicine doctor of Srinakharinwirot University, said on Monday that the symptoms were clearly of CO poisoning.

Weerasak said carbon monoxide had no smell and is caused by poor quality of internal combustion. The gas could enter the van via any leak, he added.

He said some passengers also recounted that they suffered shortness of breath before passing out.

Weerasak said shortness of breath and vomiting were also common symptoms of CO poisoning.

He recommended the van to be thoroughly fixed before it was used again.

The Yasothon land transport office has ordered the van to be suspended from services until it is fixed.

On Saturday, two passengers of the same van reportedly also passed out with similar symptoms