. >> reporter: barbara gomez, 24, is what's called a community health agent. she lives in villa canoas and her job is to knock on as many doors as she can. >> translator: our work is to register all the residents. that way we can follow them. those who have hypertension, diabetes, those who are pregnant. we work in health promotion. it's not just about addressing the problem. >> reporter: in downtown rio, we stumbled on a storefront setup offering free vaccinations against measles, mumps and rubella. a woman in line was shocked to hear from me that shots in the states aren't always free. but offering so much to so many has put a strain on the system. >> everything is given and everything is a right of everyone, and everything is free. so it is impossible, basically, doing that. >> reporter: with the current focus on primary care, it often battles for resources with brazil's hospitals. and the result, the hospitals often come up short. a recent study by the world bank called most of brazil's hospitals substandard and said that many deliver inefficient, poor qua