On February 25 I was in Vietnam, starting to worry about Covid (Vietnam looked like the most vulnerable country on earth). Had a few days to kill before my scheduled flight from Singapore https://marginalrevolution.com/marginalrevolution/2020/07/southeast-asia-coronavirus-update.html">https://marginalrevolution.com/marginalr...
Wanted to return to Sihanoukville but Cambodia seemed the only country on earth more dangerous than Vietnam. Excluded Thailand for similar reasons and flew to Penang and then Kedah in Malaysia
As you probably know, Vietnam, Thailand and Cambodia turned out to be practically Covid-proof
We don’t know why
One theory: since the virus actually comes from bats in Yunnan, perhaps there is some kind of endemic immunity along the Mekong region
Be that as it may, the mystery persists. Thailand was one of the last countries to stop flights from China and Cambodia never implemented any containment measures