the "four pests" have a long history. On February 2, 1958, the Central Committee of China and the State Council issued the Instruction on Hygiene in Eliminating Four Pests. It is proposed that the task of eliminating flies, mosquitoes, mice and sparrows should be completed in 2111 or less. Gradually, "sparrow" was rehabilitated and replaced by "bug". Later, due to changes in social life, "bugs" were replaced by "cockroaches". Therefore, the "four pests" nowadays should be flies, mosquitoes, mice and cockroaches.