c. Transmission. The method of transmission for human roundworm infection
is from humans to soil to humans. Sterile eggs are discharged in the feces of an
infected person. The eggs undergo development (embryonation) for about 3 weeks in
soil at summer temperatures. People are infected with this parasite by eating soil-
contaminated salads or other soil-contaminated foods. Soil can be carried long
distances on feet or footwear into houses and vehicles. Children frequently have heavy
roundworm infection from eating contaminated dirt. (Refer to figure 3-4.) Infection by
the roundworm Ascaris lumbricoides in the small intestine causes colicky pains and
diarrhea, especially in children.
Figure 3-4. Roundworm cycle of transmission.
SIGNS AND SYMPTOMS
a. Signs and symptoms of intestinal nematodes are as follows:
Pneumonitis (an inflammation of the lungs).
Hemoptysis (expectoration of blood or blood-stained sputum).
(5) Urticaria (vascular reaction of the skin marked by the transient
appearance of smooth, slightly elevated patches [wheals] which are redder or paler than
the surrounding skin and which itch severely).
(6) Epigastric/abdominal pain (pain in the upper middle region of the
abdomen or pain in the abdominal area).
Diarrhea (abnormal frequency and liquidity of fecal discharges).