Human pinworm, or Enterobius vermicularis, is an intestinal nematode parasite that causes enterobiasis. It is not fatal but can cause irritation when the female worms migrate to the perianal region to lay eggs. The parasite has a life cycle involving eggs that are ingested and hatch in the intestines, with adult worms mating and females migrating to lay eggs again. Diagnosis is usually by microscopic examination of perianal swabs, and treatment involves anthelmintic drugs. While found worldwide, pinworm infection is especially common in children and spreads easily through contaminated clothing and bedding. Prevention focuses on personal hygiene, handwashing, and treating entire families.

1. Human Pinworm
ENTEROBIUS VERMICULARIS

2.  Causes enterobiasis or oxyuriasis
 Not fatal but worms might go beyond
perianal region
 Intestinal nematode
 Meromyarian – in somatic muscles, there are
two to five cells per dorsal or ventral half

3. PARASITE BIOLOGY
 Adults have cuticular alar expansions at the anterior
and a prominent esophageal bulb
 Female has a long pointed tail and uteri is distended
with eggs
 Males have a curved tail and a single spicule and
because they
die after copulation
 Rhabditiform larva has
esophageal bulb and no
cuticular expansion
on the anterior end

4. PARASITE BIOLOGY
 Eggs are asymmetrical with one side flat and the
other side convex
 Translucent shell consists of an outer, triple
albuminous covering and embryonic lipoidal
membrane
 Ovum develops into
a tadpole-like embryo
 Eggs are resistant to
disinfectants but succumb
to dehydration and strive
in moist environments

6. PATHOGENESIS AND CLINICAL MANIFESTATIONS
 An innocuous parasite, rarely produces
serious lesions
 Attachment of worms=Mild catarrhal
inflammation of the intestinal mucosa
 Mechanical irritation and secondary bacterial
invasion= inflammation of the deeper layers
of the intestines
 Migration of egg-laying females to the anus=
irritation of perianal region

7.  Intense itching = secondary bacterial
infection
 Pruritus= insomia
 Adult worm migration=
appendicitis, endometritis, salpingitis and
peritonitis
 Other signs: poor appetite, weight
loss, irritability, grinding of teeth, abdominal
pain
 Familial disease

8. DIAGNOSIS
 Perianal itching
 Microscopic examinations
 Graham’s scotch tape swab or perianal
cellulose tape swab

9. TREATMENT
 Pyarantel pamoate, albendazole, mebendazole
 Secondary dose may be necessary
 Cure only after seven perianal smears
 Egg reduction rate are hard to determine
because eggs are from perianal area and not
from feces
 Contradictions to drugs: pregnancy and
hypersensitivity
 Effects of drugs: gastrointestinal distrubance,
headache

10. EPIDEMIOLOGY
 Both temperate and tropical
 Both developed and under developed
countries
 Cannot be controlled by sanitary disposal of
human feces
 Contaminate underwear
and beddings

11. EPIDEMIOLOGY
 route of infection: mouth, respiratory
system -> anus
 Retroinfection: when they go back to large
intestine
 208.8 million people are infected
 In Philippines: 29% schoolchildren from
private schools; 56% from public school

12. EPIDEMIOLGY
 Prevalence is higher in females
 Eggs from nails
 Migration of female worms to perianal area
during night time

13. PREVENTION AND CONTROL
 Personal cleanliness and hygeine
 Short nail
 Frequent handwashing

14. PREVENTION AND CONTROL
 Showers and not bath tubs
 Underwear, night clothes, blankets
bedsheets- handled with care, boiled,
laundered
 Chemotherapy for entire family

15. THE END :>