DOTS is effective for TB because it’s a time-limited treatment (usually 4 months for drug susceptible strains of TB) and is only relevant for treating infected individuals

DOTS wouldn’t be feasible for a prophylactic treatment like this as the number of participants would be huge and the treatment period is indefinite (ie: the patient’s lifespan)

> Directly observed treatment

For a sexually transmitted disease? Harder than you'd expect, considering people are reticent about their private lives.

> short-course

This needs to be continued forever, as far as I understand.

It's also quite expensive