Due to continued increase in cases of syphilis, some health departments have started implementing mass treatment for syphilis. This involves the prophylactic intramuscular administration of penicillin G (or if penicillin-allergic, be given doxycyline tablet for 2 weeks) to individuals with high risk sexual behaviors (having more than one sex partner in the last 60 days or having anonymous sex). This is done in the hopes of preventing the onset of incubating syphilis and its subsequent transmission. Opponents of this intervention cite possible behavioral consequences (individuals being more likely to engage in high risk behaviors after prophylaxis as it can make them feel “invincible”) can lead to worse outcomes. However, the target population for this intervention are already engaging in high risk behaviors. Therefore, there should be not much of a change there. Another point they raise is that some programs who did the intervention ended up with rate rebound (after the intervention, the number of cases was higher than expected). However, there are other programs who had success with mass treatment of syphilis. This just argues that the intervention should not be done routinely and that each program’s situation should be analysed first to see where the main transmission of the disease occurs so as to determine whether it can benefit from the intervention. One more issue is the risk of the development of resistance to penicillin. Then again, penicillin has been used for syphilis for decades now and and it is still the best drug for it (no development of resistance has really occurred).