When my partner and I did IVF I got pretty good at giving subcutaneous and intramuscular injections. The medications have to be given at set times every day so

When my partner and I did IVF I got pretty good at giving subcutaneous and intramuscular injections. The medications have to be given at set times every day so there's no way to get them at a doctor's office. I had to mix lyophilized medication and inject it using a hypodermic needle and syringe. It's not impossible to train lay people to inject most vaccines that I've seen. Does the polio vaccine have to be injected into a specific organ or the bloodstream? Or is it subcutaneous or intramuscular? If the latter this is a solvable problem by organizing aid workers or by forming a small network of competent locals, distributing lyophilized vaccine, training, and having vaccination clinics.