Α) wear a condom and so avoid any major problems to your own health
B) when fucking prossies, allow two weeks if you have an O/H to fuck (which gives you time to check out any merely embarrassing problems).
statistics mean nothing if you happen to be unlucky, so best to follow the rules with all fanny-poking (not that much point in differentiating between nationalities or even civvies vs paid in that sense)