As a result, 18 of these uninfected people (.0018 times 9,990) would be declared antibody-positive, or infected.
The program aims to strengthen bonds between infected and uninfected people.
So Federal officials say they could order testing in these areas, both to measure the prevalence of the virus and to help protect uninfected people.
The final chapter, "The Survivors," tells the story of a larger group of uninfected people who have set up camp on a farm.
"You don't want to represent that to the uninfected people in our community."
Existing vaccines against polio, measles and several other diseases are used to protect uninfected people.
A series of shots (vaccine) are available to protect uninfected people from hepatitis B virus.
Salk is hoping eventually to try the vaccine on uninfected people.
The researchers have been given permission to expand the program to other infected people and are seeking approval to try the injections on uninfected people.
