Fact: SIDS is also called "cot death" or "crib death" in the UK and the US.
Fact: In Japan and most other countries around the world, co-sleeping is still the norm.
For the year 2010:
The population of Japan was 128,057,352. The number of SIDS deaths was 147.
The population of the US was 308,745,538. The number of SIDS deaths was 2,063.
Japan SIDS research site
US SIDS research site.