Question 4
The diagram bellow illustrates a worm infested in humans. Study it carefully and answer questions 4(a), (i), (ii), (iii), (b) and (c)
- State two observable symptoms of the infested part. [2 marks]
- State three measures to be adopted in preventing the worm infestation. [3 marks]
I. Name the worm illustrated in the diagram. [1 mark]
II. Mention the intermediate host associated with the worm named in 4(a) (i) [1 mark]
III. Mention three sources of infection of the worm named in 4(a)(I) [3 marks]
Observation
Many candidates attempted this question and their performance was fair. In part (a) (i) some candidates were unable to identify the worm illustrated in the diagram. In part (a) (ii) few candidates got this part correctly. In part (a) (iii) majority of the candidates answered it correctly. In part (b) few candidates were able to mention correctly observable symptoms of the infested part. In part (c) majority of the candidates stated correctly measures to be adopted in preventing the worm infestation.
The expected answers are as follow:
(a) (i) Name of the worm illustrated in the diagram
- Guinea worm / Dracunculus
(ii) Intermediate host
- cyclops / water fleas
(iii) Sources of infection
- wading/bathing in contaminated/infected water
- drinking from stagnant water containing water fleas / cyclops
- drinking contaminated/infected river/stream / pond / lake water
(b) Observable symptoms of the infested part by the worm illustrated
- sore on the leg/blister
- threadlike structure from the spot of blister /sore
- inflammation / swelling of the infected part
(c) Measures to be adopted in preventing the worm infestation
- avoid wading/bathing in infected water
- patient with guinea worm infestation should be handled by a
trained personnel
- drinking clean water / sterilized water before drinking
- cyclops / intermediate hosts should be destroyed
- victims of guinea worm infestation should desist from bathing/wading in river/stream water