The best method to prevent STDs and UTIs would be to abstain from sex entirely, which is impossible. However, the opportunities to have sex can be minimized by keeping people busy. Chores and other tasks that keep the household and the community running will be a great way to keep people from meeting up for passionate encounters. Aside from that, nature has several ways of reducing the risk of contracting STDs and UTIs. (h/t to BackdoorSurvival.com)
Mainstream anti-STD medicine will be largely unavailable in a post-SHTF world. Condoms will be handy but will only be around for so long before they have all been used up or have expired. Stockpiling them could be a good idea, especially if your community has a lot of teenagers and young adults. (Related: Prepping tips for women: Natural birth control methods you can use in a post-SHTF world.)
Prescription antibiotics that can help get rid of STDs are riddled with side effects and will also disappear quickly. Luckily, there are several natural antibiotics that are within reach:
The listed remedies will work well against many STDs. UTIs, however, are a different story as they are more likely to occur than STDs, with the American Society for Microbiology stating that many UTIs go misdiagnosed. Luckily, UTIs are much easier to treat.
Flushing out bacteria will be your prime defense against UTIs. Drinking copious amounts of water will ensure frequent urination – in this way, the bacteria in your urinary tract won't have time to settle and harm you before it's flushed out. Observing proper genital hygiene will also go a long way. Wiping properly after relieving yourself helps prevent bacteria from spreading and causing UTIs.
Being prepared for SHTF scenarios includes preventing and treating STDs and UTIs, and if you follow the necessary precautions, you can reduce the risk of contracting these infections. In a post-SHTF world, reducing risk is paramount to survival.