Not all people would agree to this....or any solution for that matter.

There are many std's, each with differing levels of permenance or treatment durations.

It is possible to carry a disease and not be aware of it.

Some promiscuous people simply may not care.

People have varying levels of personal hygiene.

Many variables may make people lie about their health.

It is possible, though far less likely, for STDs to spread through nonsexual means of contact.