Human African Trypanosomiasis Trypanosomiasis, also called sleeping sickness, is caused by the protozoan parasites Trypanosoma brucei gambiense or Trypanosoma brucei ... and is most commonly found in ...

They've existed for about 600 million years. There are about 34,000 different types of worm; many are so small you wouldn't be able to see them without a microscope! Worms are hermaphrodite ...

Another parasitic worm, Clavinema mariae, which doesn't cause illness in humans, increased its numbers eight times in local English sole since the 1930s. Wood says that normal public-health ...