  Tuberculosis (TB) and human immunodeficiency virus (HIV) can be considered a
deadly human syndemic. In this article, we formulate a model for TB and HIV
transmission dynamics. The model considers both TB and acquired immune
deficiency syndrome (AIDS) treatment for individuals with only one of the
infectious diseases or both. The basic reproduction number and equilibrium
points are determined and stability is analyzed. Through simulations, we show
that TB treatment for individuals with only TB infection reduces the number of
individuals that become co-infected with TB and HIV/AIDS, and reduces the
diseases (TB and AIDS) induced deaths. Analogously, the treatment of
individuals with only AIDS also reduces the number of co-infected individuals.
Further, TB-treatment for co-infected individuals in the active and latent
stage of TB disease, implies a decrease of the number of individuals that
passes from HIV-positive to AIDS.
