Summary: A bacteria-immunity model with bacterial quorum sensing is formulated, which describes the competition between bacteria and immune cells. After periodic perturbation and a series of coordinate transformations, the model is brought into a standard form, and which is amenable to Melnikov method. By the method, the existences of chaotic motion and homoclinic bifurcations are proved.
Editorial remark: There are doubts about a proper peer-reviewing procedure of this journal. The editor-in-chief has retired, but, according to a statement of the publisher, articles accepted under his guidance are published without additional control.