Define the following diseases, causing agent and symptoms.
Amoebiasis, Ring worm, Ascariasis, Filariasis. »

Explanation

. (a) Amoebic Dysentery (Amoebiasis) : It is caused by Entamoeba histolytica. Infection is through contaminated food and water.
The pathogen resides in the large intestine.
Its symptoms include:
(i) Abdominal pain and cramps.
(ii) Stools with excess mucus and blood clots.
(iii) Constipation alternating with diarrhoea.
Houseflies act as mechanical carriers and transfer the parasite from the faeces of infected person to the food articles and water.
(b) Ringworms : These are caused by fungi like Microsporum, Epidermophyton and Trichophyton.
The symptoms include:
(i) dry scaly lesions on skin, nails and scalp.
(ii) lesions are accompanied by itching.
Ringworms are generally acquired from soil or by direct contact with the contaminated particles used by the infected persons.
(c) Ascariasis: It is caused by Ascaris lumbricoides. (round worm).
Its symptoms include:
(i) Blockage of intestinal passage, (ii) Anaemia,
(iii) Abdominal/muscularpain,
(v) Nausea and
(iv) Internal bleeding,
(vi) Headache.
Infection is through contaminated vegetables, fruits and water as eggs of parasite excreted by the infected persons contaminate soil, plants and water.
(d) Filariasis/Elephantiasis
- It is caused by Wuchereria bancrofti and Wuchereria malayi (filarial worms).
- They normally cause inflammation of the organs in which they live for many years.
- Genital organs may also be affected leading to gross deformities.
- Female Culex mosquito is the vector.