Prostitution Probably Not Source of HIV Epidemics

Swedish researchers have been inconspicuously monitoring the Brazilian sex industry, trying to understand the patterns of interaction between prostitutes and their clients. Using this data they analyzed how HIV would spread within the sex industry and whether it could be a source of an epidemic. Quite surprisingly, the researchers claim that prostitution, at least of the variety studied in Brazil, does not seem to have the pattern necessary to lead to an epidemic.
From The Physics arXiv Blog:

Earlier this year, we looked at some interesting work by Luis Rocha at Umea University in Sweden and a couple of buddies who studied a public website in Brazil in which men have graded and categorised their sexual encounters with female escorts over a period of six years. The researchers then used this data to reconstruct the network of links between prostitutes and their clients, both in time and in space.
That’s an impressive data set amounting to over 50,000 encounters between 16,000 people. “Our data set covers, we believe, the escort business of Brazil rather completely,” say Rocha and co.
Today, they take this work further by asking how well a sexually transmitted disease might spread through such a network. The answer is surprising.
Rocha and co study the spread of HIV in particular. They point out that a key factor in the spread of the disease is the viral load. During the chronic infection stage, the load is low enough that it requires several contacts between two individuals over a short period of time for the infection to spread.
This kind of contact is rare in the network that Rocha and co have uncovered.

The Physics arXiv Blog: Prostitution Unlikely To Cause HIV Epidemics…
Article in arXiv Physics and Society: Simulated epidemics in an empirical spatiotemporal network of 50,185 sexual contacts…