An improved acquaintance immunization strategy for complex network.

The acquaintance immunization strategy is a common strategy to suppress epidemic on complex network which achieves a seemingly perfect balance between cost and effectiveness compared with other canonical immunization strategies. However, the acquaintance immunization strategy fails to take the time-varying factor and local information of nodes into consideration, which limits its effectiveness in some specific network topology. Our improved immunization strategy is based on a new mathematical model Network Structure Index (NSI), which digs deep to measure the connection property and surrounding influence of a node's neighbor nodes to better determine the importance of nodes during immunization. Both mathematical derivation and the simulation program tested on various network topology support our idea that this improved acquaintance immunization strategy protects more nodes from infection and immunizes important nodes more efficiently than the original strategies. As to say, our strategy has more adaptability and achieves a more reasonable balanced point between cost and effectiveness.