I have reservations about the rather quaint old notion that seafarers are at higher risk of STDs than other classes of OCW.
Seafarers don't get much chance of a "run ashore" these days, as their ships turn round in port very quickly, and you won't find much of a red light district in a container terminal, an oil refinery or a steelworks.
Furthermore, seafarers tend to be well aware of the risks.
Shore based contract workers are at higher risk - they have far more opportunities - and the one group who are at extremely high risk are female "entertainers", as supplied in huge numbers (100,000 annually to Japan alone!) to red light districts across the world.
