Many people have an aversion to insects for good reason. Some bugs actually live and feed on the human body. Insects including mosquitoes, fleas, and ticks can transmit diseases to humans. As they feed, they may transfer parasitic protozoans, bacteria, or other pathogens that can cause serious diseases including Lyme disease, Q fever, Rocky Mountain spotted fever, malaria, and African sleeping sickness. The association of bugs with disease makes us wary of bugs and creates a desire to avoid them in order to keep safe. Another reason that people dislike insects is because of how they look. Insect anatomy is totally foreign to ours — some bugs have many more appendages, eyes, or other body parts than humans. The way insects move may also give some people a creepy feeling or even the sensation that something is crawling on them. To others, insects encroach upon their sense of environmental control. They invade our personal space and may even crawl on personal hygiene items. This invasion upsets our sense of safety and cleanliness. Insects can also evoke feelings of disgust or revulsion. This instinctive response varies culturally and is related to our natural tendency to reject things that may make us sick.