A social model for the evolution of sexually transmitted diseases

S. GONCALVES; M. N. KUPERMAN; M. FERREIRA DA COSTA GOMES

PHYSICA A - STATISTICAL AND THEORETICAL PHYSICS

Año: 2004 vol. 342 p. 256 - 262

0378-4371

We have introduced recently a model for the spread of sexually transmitted diseases, in whichthe social behavior is incorporated as a key factor for the further propagation of the infection.The system may be regarded as a society of agents where in principle anyone can sexuallyinteract with any other one in the population. The social behavior is taking into account bymeans of two parameters: the fraction of singles ps and the promiscuity p. The promiscuityparameter defines the per individual daily probability of going out to look for a sexual partner,abandoning its eventual mate. In this contribution we show that the interaction between thistwo parameters give rise to a non-trivial epidemic threshold condition, when going from thehomogeneous case (ps = 1) to heterogeneous cases (ps>1). These results can have profoundimplications in the interpretation of  real epidemic data.