2. Phylum Nematoda
Present in all kinds of environment
12,000 known species
The effects of roundworms on crops, domestic
animals and humans make it one of the most
parasitic animal groups
About 50 species are plant and animal parasites
that cause damage
3. Ascaris
The large roundworm of humans
Live in host’s intestines and eggs pass out feces
Extremely resistant to adverse conditions
Present in Uncooked veggies, soiled fingers or toys
Make their way up through trachea and get swallowed
again so that they can grow to maturity in the intestines
Cause allergic reactions and intestinal blockage.
4.
5. Hookworms
Hook into intestinal wall
Feed off host’s blood causing anemia
In children can cause retarded mental and physical
growth
Travels through the blood to the lungs and into the
throat where it is swallowed
Eggs are shed in hosts feces and hatch on warm moist
soil
Larvae then bore through the feet of a new host
6.
7. Trichina worm
Cause lethal disease trichinosis
Humans get by eating undercooked pork that is
contaminated with trichina
Penetrate blood vessels and any tissue or space
8.
9. Pinworms
Cause little disease, but most common
Live in large intestine and migrate to anal region
to lay eggs
Most worms found by viewing feces under a
microscope, but pinwarm can be found by
scotch tape method.
10.
11. Filarial worm
Usually found in people in tropical countries
Live in lymphatic system
Cause inflammation and obstruction of the lymphatic
system
– Example: elephantitis.
