Bizarro bloodsuckers

"This . . . book explores the strange science behind the bloodsuckers that surround us, including mosquitoes, head lice, and fleas. These critters can be irritating and sometimes even deadly, spreading terrible diseases such as malaria and the bubonic plague, which have killed millions. Students may be surprised to discover that bloodsuckers also help people. This text discusses how scientists are turning the chemicals blood drinkers produce into medicines and how doctors still use leeches to heal injuries"--Provided by publisher.