Primary and Secondary Prevention

Hello again! I found a journal artical here but I don't quite understand it. I only understand that it states various ways to prevent aids (mass media, healthcare institutions, etc) and that there are two main ways - Primary and secondary prevention.
Primary is preventing individuals from becoming infected in the first place and secondary is preventing disease progression in those already infected.

It also states that "Social networks and community norms influence each step in the behavior change process (Fisher, 1988). Perceiving sexual behavior as risky depends on knowledge of risky sexual activities and on the belief in personal susceptibility. Networks and norms can influence how the individual labels the risky behavior by (a) influencing the person's level of health knowledge, (b) funneling people toward appropriate health decisions by providing sanctions for continued high-risk activities, and (c) sanctioning the presence in the environment of individuals whose high-risk behavior leads to disease. Social networks and community norms can also inhibit an individual from labeling behavior as a problem. The fear of being stigmatized for admitting socially undesirable behavior may decrease an individual's willingness to perceive his or her behavior a problem. If a health-diminishing behavior has acquired political or fiscal value within a community, the community may support the activity, despite awareness of health risk."

Do give it a read. Thanks.