2. Ancylostoma duodenale
Old world hookworm
Ancylostomiasis
Italian Physician Dubini (1843) - autopsy material
Milanase woman
Looss (1896) – mode of infection and pathogenesis
3. Habitat
Lumen of small intestine ( jejunum and ileum)
Remain attached to the intestinal wall by their
mouth parts.
4. MORPHOLOGY
Adult worm
Cylindrical , greyish white and slightly curved
The anterior end is bent slightly in the same direction
of the body curve and gives it name hookworm
5. Females:
9-13 mm long with
egg-filled uterus
Male hookworms:
7-11 mm long
Posterior end forms a
bell shaped bursa
6. Morphology of Ancylostoma duodenale
Buccal capsule contains 2 pairs of large ventral (anterior) teeth
Copulatory bursa is at posterior end and contains 2 thin spicules
that separate distally.
7. Morphology of Necator americanus
Buccal capsule contains a pair of ventral and dorsal cutting plates.
Copulatory bursa contains spicules that are fused distally.
8. Male worm
o 8-11mm long, 0.4mm thick
o Posterior end of male is expanded into a copulatory
bursa supported by fleshy rays
o Rays help in differentiating between species
o rectum and genital canal open into Cloaca in the
bursa
o 2 long retractile bristle like copulatory spicules, tips of
which project from the bursa
9. Morphology (contd.)
Female worm
o Larger, 10-13mm long, 0.6mm thick,
o Vulva opens ventrally, at the junction of middle and
posterior thirds of the body
o Vagina leads to 2 intricately coiled ovarian tubes
o During copulation, copulatory bursa attaches to
the vulva Y shaped appearance
14. Routes of transmission
Penetration of skin
Ingestion of filariform larvae
Breast milk from mother to infants(
transmammary transmission)
Transplacental transmission
19. Pathogenesis and pathology
Mainly by presence of adult worms in the
intestine
Less frequently , by the penetration of , and
migration of infective larvae within skin.
20. Host immunity
Hookworm infection may confer immunity and
eliminate hookworms from the gut.
Repeated infections by the larvae in the circulatory
system and respiratory tract may evoke a strong
immune response.
Immediate hypersensitivity reactions
21. Clinical manifestations
Skin manifestations
Ground itch most important
Observed after 7-10 days
Seen around feet
Intense itching , edema , erythema and rash
Secondary bacterial infection aggravate
22. Respiratory manifestation
Low grade fever
Mild cough
Pharyngitis
Dyspnoea
Hemoptysis
Dyspnoea may be triggered when worms first break
through from venous circulation into lung alveoli.
Pneumonia with pulmonary consolidation
Bronchitis
23. Intestinal manifestation
Low grade fever
Anaemia
Nausea
Vomiting
Diarrhea
Abdominal discomfort
Iron deficiency anaemia and hypo- albuminaemia
are the major clinical manifestations.
24. Diagnosis
Difficult to diagnose clinically
Eosinophilic leukocytosis and hypochromic
microcytic anaemia may be suggestive of the
condition in the endemic areas.
25. Laboratory diagnosis
Parasitic diagnosis
Specimen:- Stool
Method of examination
1. Stool microscopy
2. Stool concentration(Kato Katz method)
3. Stool culture( Harda Mori method)
4. Imaging methods
5. Other test( Charcot Leyden crystals and occult
blood)
26. Treatment
1. Treatment of worm infection by anthelminthic
2. Treatment of iron deficiency anaemia with
replacement iron therapy
Treatment of worm infection by anthelminthic
Mebendazole (100 mg twice daily for 3 days)
Pyrantel Pamoate( single dose of 11mh/kg/body wt.,
max 1gm)
Thiabendazole (25mg/kg body wt. for 2 days)
27. Treatment contd.
Treatment of anemia
Carried out by giving a high protein –diet ,
supplemented with oral iron preparations.
Ferrous sulphate given orally in a dose of 200 mg to
400 mg daily depending on the tolerance of the
person
Folic acid and vitamin B12
28. Prevention and control
1. Sanitary disposal of human feces
2. Treatment of infected person
3. Use of sanitary latrines, and use of foot wears and
4. Health education with improved nutrition
supplemented with dietary iron.