Parasites in Kingdom Animalia: The Nematodes (Roundworms)

Question 1

Ascaris lumbricoides

 * Ascaris lumbricoides male cross-section
 * Ascaris lumbricoides female c-s
 * Ascaris lumbricoides ova

Answer 1

disease: Ascariasis,roundworm disease
symptoms: Eggs hatch in duodenum, then larvae penetrate mucosa and enter lymph vessels; they then get into blood circulation, pass through right heart, and break out of capillaries. They may get lost in any tissue at this point, causing inflammation. Others get to the lungs, causing pneumonitis and secondary bacterial infections. They move up to the pharynx as sputum is coughed up; they are then swallowed. By this time they have molted four times and arrive in the intestine as adults, where they produce fertilized eggs. In the intestine they mainly eat liquid contents of the lumen and cause abdominal pain. Metabolites induce responses such as rashes, eye pain, asthma, insomnia, and restlessness. Massive infections can cause fatal intestinal blockage, especially when antihelminthics are given. If no males are present, females will wander to the appendix, anus, bile ducts, liver, stomach, and may even be vomited out.

Question 2

Necator americanus(New World)
*Necator americanus,ova
*Ancylostoma caninum,whole female
Ancylostoma duodenale(Old World)

Answer 2

disease: Hookworm disease
symptoms:There are three phases of disease:
Invasion phase: Little damage occurs as larvae penetrate skin, but they then attack blood vessels, bringing about a tissue reaction that may kill the larvae. Pyogenic bacteria may enter. Occasionally larvae from hookworm species that don’t usually infect humans will penetrate human skin. These larvae cannot get to the intestine, but can tunnel through the skin, leaving a red itchy wound that may become infected. This is called cutaneous larval migrans, or creeping eruption.
Pulmonary phase: Juveniles get out of lung capillaries into alveoli, then pass up the bronchii to the throat; dry coughing and sore throat, possibly pneumonitis in severe infections.
Intestinal phase: The adult worm attaches to mucosa with denticles and feeds on blood. It periodically moves from site to site on the intestinal wall. Iron deficiency anemia results, and symptoms include intermittent abdominal pain, loss of appetite, and in some cases, desire to eat soil. In heavy infections, resulting protein deficiency causes dry skin and hair, edema, mental dullness, heart failure, and possibly death.

Question 3

Enterobius vermicularis

 * Enterobius vermicularis male adult worm
 * Enterobius vermicularis female
  * Enterobius vermicularis ova

Answer 3

disease: Pinworm disease
symptoms: One third of infections are asymptomatic. In symptomatic patients there may be minute ulcerations of intestinal mucosa, along with mild inflammation. Laying of eggs at anus causes itching. Children with pinworms may be nervous, irritable, and restless, and may have loss of appetite, insomnia, and weight loss. Occasionally a nose infection occurs as a result of nose-picking, and infection of the vagina occurs rarely.

Question 4

Trichuris trichiura

 * Trichuris trichiura whole
 * Trichuris trichiura,ova

Answer 4

disease: Whipworm disease
symptoms: Whipworms damage the mucosa by sewing themselves into the intestinal lining with a buccal spine. They feed on blood cells and digested materials. Asymptomatic when 100 or fewer worms. If over 100 worms, loss of appetite, diarrhea, bloody stool, abdominal pain, anemia, and secondary infections may result; allergic reaction to the worms’ metabolic wastes cause colitis or proctitis. An excruciatingly painful prolapsed rectum can occur if there is a severe irritation and allergic reaction. The adult worms can be seen in the prolapsed tissue. The adult worms live up to 7 years in human intestine

Question 5

Trichinella spiralis

* Trichinella spiralis,larvae in muscle

Answer 5

disease: Trichinosis
symptoms: Three stages of disease:1) Penetration of female adults into intestinal mucosa to give birth causes damage to mucosa, inflammation, vomiting, host reaction to metabolic waste of worm, and possible secondary bacterial infection. 2)Larval migration stage leads to damage to blood vessels, pleurisy, myocarditis, and nephritis. 3)Intramuscular stage with muscular pain, especially in swallowing and breathing muscles, eye muscles, and in arms and legs.