Cause. It is caused by Ascaris lumbricoides. (round worm).

Symptoms. Its symptoms include : (a) Blockage of intestinal passage, (b) Anaemia, (c) Abdominal/muscular pain, (d) Internal bleeding, (e) Nausea and headache.

Modes of transmission. Infection is transmitted through contaminated vegetables, fruits and water as eggs of parasite excreted by the infected persons contaminate the soil, plants and water.

(ii) Filariasis/Elephantiasis.

Cause. It is caused by Wuchereria bancrofti and Wuchereria malayi (filarial worms).

Symptoms- Normally the lymph vessels of the lower limbs are affected causing them to swell like that of an elephant, hence also called elephantiasis.Genital organs may also be affected leading to gross deformation.

Modes of transmission. It is transmitted by female Culex mosquito that acts a vector.

(iii) Ringworms.

Cause. These are caused by fungi like Microsporum, Epidermophyton and Trichophyton.

Symptoms. The symptoms include : (i) dry scaly lesions on skins, nails and scalp, (ii) lesions are accompanied by itching.

Modes of transmission. Ringworms are generally acquired from soil or by direct contact with the contaminated articles used by the infected persons.