Interesting following up on the death of two backpackers on Ko Phi Phi in 2012. Seems pesticides may have been the true cause of their death.
"The most likely explanation is the acute intoxication and it is intoxication from the chemical that belong to the pesticide group,-Dr. Pasakron Akarasewi, with Thailand's Ministry of Health, told the CBC/Radio-Canada investigation."
Full story here
I think an Australian TV documentary came to a similar conclusion about the deaths in Chiang Mai. The trouble is, if a tourist starts to feel a bit woozy, she is most likely to think she is coming down with a bug and stay in the room.
Several years ago, late at night, I was trying to get a guesthouse in Sumatra to do something about the numerous mossies in my room and they bought in what looked like a fire extinguisher and started pumping out clouds of god knows what. I finally got the over-keen pumper to stop and hoped it would be OK if I left the door open for a while. Twenty minutes later, as I watched the 12th cockroach flee the room, I decided I didn't want to risk sleeping there so I tip-toed to another empty room and slept there.
I had my SLR stolen from the old room but after reading several stories about insecticide use, I'm pretty glad I moved!