Overview
The Four Pests campaign, was one of the first actions taken in the Great Leap Forward in China from 1958 to 1962. Authorities targeted four pests for elimination: rats, flies, mosquitoes, and sparrows. The extermination of sparrows - also known as the smash sparrows campaign or the eliminate sparrows campaign - resulted in severe ecological imbalance, being one of the causes of the Great Chinese Famine of 1959-1961. In 1960 the campaign against sparrows ended and bed bugs became an official target.
Campaign
The "Four Pests" campaign was introduced in 1958 as a hygiene campaign aimed to eradicate the pests responsible for the transmission of pestilence and disease:
the mosquitos responsible for malaria
the rodents that spread the plague
the pervasive airborne flies
the sparrows—specifically the Eurasian tree sparrow—which ate grain, seed, and fruit
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