Under the Microscope
Full body shudders, right? But as disgusting as parasites are, they're also elegant examples of evolution. The following images reveal these dangerous organisms in microscopic detail.
A tick-borne bacteria
The dreaded tapeworm
Invading the blood
Sheep liver fluke
Spread through snails
Many people carry hookworms in their intestines without symptoms, but the parasites can cause gastrointestinal distress and sometimes anemia.
To extract the worm more swiftly, doctors often try to wrap it around a stick, slowly winding it out of the wound over several days. Because female guinea worms can grow up to 31 inches in length (80 centimeters), this is a slow, disgusting and painful process.
Adult female flies spread their eggs to humans in a surprising way: They snag a mosquito or tick and lay their eggs on the unsuspecting vector's body. When the insect goes on to bite a person, the eggs or hatched larvae drop off and enter the skin, where they develop for a couple of months before emerging to complete their life cycle as free-living organisms. During the larval stage, the maggots are often visible as small bumps and must be surgically removed from the skin.