Threadworms,
or pinworms, are small intestinal worm parasites
that commonly infest children in all parts
of the world, though careful washing of
hands, and good hygiene will reduce the
risk of passing them to others. The threadworm,
Enterobius vermicularis, is the commonest
worm parasite of children in temperate areas.
At least 20 per cent of all children are
affected at any one time.
The mature
female worm is about a centimetre long,
white, and with a blunt head and a fine,
hair-like, pointed tail. The male is shorter
and is rarely seen, as it remains in the
intestine. It is unlikely that threadworms
ever do any real harm except to disturb
the sleep of children and worry parents.
Symptoms
Threadworms
cause a tickling or crawling sensation around
the anus.
Causes
The pregnant
female worms moving on the skin around the
anus to deposit their eggs cause a strong
tickling sensation. The child scratches
and the eggs stick to the fingers and nails.
These are then transferred, either directly
to the mouth to cause re-infestation of
the intestine, or to other children by way
of toys, blankets, etc.
The eggs
can survive for three weeks and sometimes
hatch on the skin and re-enter the bowel.
Swallowed eggs hatch in the intestine, and
the worms reach adult size and begin to
reproduce after two to six weeks.
Treatment
If re-infestation
is avoided, the problem will disappear spontaneously
within a month. Ointments may be used to
soothe the anal itching, and there are various
effective de-worming drugs, such as mebendazole,
piperazine or pyrantel. Treatment of all
the members of the family is, however, necessary.
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Threadworms
