1. It's not an infection, it's untreated heart failure. When your heart stops functioning properly on the right side, it makes fluid back up in your circulatory system. This can lead to "ascites" or those giant hard bellies you see. It can certainly and more commonly lead to swollen legs. The fluid gets backed up and usually sits in the legs and belly. There can be so much of it that it begins to ooze out, giving it that color and moistness. They're not exposing you to contagious disease. Older folks get it often and it's controlled with diuretics and blood thinners.
2. Hospitals can sign them up for Medicaid and emergency Medicaid. But most of these folks refuse because of mental illness. And the hospital can put you in a psyche ward under certain circumstances. And they're afraid of losing their freedom or of being judged or maybe they have paranoid delusions and don't realize they're sick. And some simply don't know they qualify for free treatment.,,
Im an EMT in NY and we deal with homeless folks a lot. They're usually not as dangerous as people think. They're mostly just sad, alone, sick or addicted and very smelly.