Are there herbal supplements that can prevent a bacterial infection?

Unfortunately, no: There are thousands of supplements advertised to do all sorts of magical remedies. Very few supplements have real research studies to show benefits (but manufacturers make claims, based on theories, animal tests, testimonials, chemical similarities, etc... But not on real research because real research is hard & expensive to do). No supplement has been shown to prevent any particular infection.

Yes: Most herbal supplements boost the immune system. Try asking at a health food store.