The Tipping Point
Chapter One
The Three Rules of Epidemics
In the mid-1990s, the city of Baltimore was attacked by an epidemic
of syphilis. In the space of a year, from 1995 to 1996, the number
of children born with the disease increased by 500 percent. If you
look at Baltimore's syphilis rates on a graph, the line runs
straight for years and then, when it hits 1995, rises almost at a
right angle.
What caused Baltimore's syphilis problem to tip? According to the
Centers for Disease Control, the problem was crack cocaine. Crack is
known to cause a dramatic increase in the kind of risky sexual
behavior that leads to the spread of things like HIV and syphilis.
It brings far more people into poor areas to buy drugs, which then
increases the likelihood that they will take an infection home with
them to their own neighborhood. It changes the patterns of social
connections between neighborhoods. Crack, the CDC said, was the
little push that the syphilis problem needed to turn into a raging
epidemic.
John Zenilman of Johns Hopkins University in Baltimore, an expert on
sexually transmitted diseases, has another expl ... read full excerpt from: The Tipping Point: How Little Things Can Make a Big Difference ebook
