W
- Wart (verruca)
- A small, hard, benign growth in the skin, caused by a virus.
- Whitlow
- An infected fingernail.
- Whooping Cough (pertussis)
- A disease produced by the bacterium Bordetella pertussis, producing coughing spasms, followed by an intake of breath that sounds like a "whoop."
- Worms (helminths)
- Any soft-bodied elongated, naked invertebrates of the phyla Annelida, Acanthocephala, Aschelminthes, and Platyhelminthes. They are of special interest to humans as many of them cause parasitic diseases. Worms are also known as nematodes (roundworms), trematodes (flukes), and cestodes (tapeworms), and are the result of unsanitary conditions in the environment. Human infestations are the result of a weakened immune system.
