Hookworm Infestation
- 1. HOOKWORMINFESTATION By: DR. SAURAV POUDEL 16th October 2016. 16th October 2016
- 2. Prevalence of Hookworm • Hookworm affects about 576 million people globally • Predominates in tropic and subtropic regions • Disease of developing and under-developed world, disease of the poorest of the poor • Most vulnerable: – Children – Pregnant women – Persons without shoes or adequate protective clothing – Agriculturalists
- 4. Offending Pathogens Majority of hookworm infections in humans caused by 1) Ancylostoma duodenale (an-cy-CLO-sto-ma doe-AH-den-al) 2) Necator americanus (ne-KAY-tor am-er-i-CON-us)
- 5. N. americanus and A. duodenale • 0.10 mm length, 0.4 mm diameter. Female > Male • 9000 eggs/day, eggs have 3-5 yrs survival • Buccal capsule set with two crescent-shaped cutting plates on ventral side • Ingests 30 µl blood/day • 12 mm in length, 0.6 mm in diameter. Female > Male • 20,000 eggs/day, eggs have 1 yr survival • Buccal capsule set with symmetric pair of sharp teeth on ventral side. • Ingests 260 µl blood/day
- 6. Hookworm Egg and Larvae
- 9. Ancylostoma duodenale Common name: Old world hookworm Habitat: Small intestine Definitive host: Human Route of infection: Filariform larvae penetrate the skin of human Infective stage: Third stage larvae ( filariform) Diagnostic stage: Eggs in Stool Disease: Hookworm infection, Ancylostomiasis Geographic Distribution: Southern Europe, North parts of Africa, China, India, and Japan.
- 11. Egg • Shape : oval with an empty space between the shell and content • Size: 60 x 40 μm • Shell: thin egg shell • Color: colorless and transparent • Content: 4-8 cell unembryonated • Immature eggs pass in feces (20,000 eggs ⁄ day).
- 13. Clinical manifestations: 1-Invasion stage: The skin, at the site of entry of filariform larva Maculopapular lesions “ ground itch” or “dew itch” Itching, edema. 2-Migration stage: passage of the larvae in the lung leads to: Haemorrhages and pneumonia, cough, fever, eosinophilia.
- 14. Ground itch or “dew itch”
- 15. 3-Intestinal stage: 1) sucking of blood by the worm (iron-dificiency anaemia ), • Severe anaemia leads to weakness. • 0.15-0.26 mL of blood may be withdrawn by a Ancylstoma in 24 hour. • Approximately 50% of the red blood cells are hemolyzed 2) Bleeding at the site of attachment and after movement to a new sites. 3) Toxic substances . -intestinal ulcers: flatulence, nausea, vomiting ,diarrhea.
- 16. Symptoms Associated with Infection • Skin Infection – stinging, burning, itching, pruritus, papulovesicular rash - can last up to 2 wks • Lung Infection – pneumonia, cough --rare and mild. • Ingestion – throat soreness, hoarseness, nausea, vomiting • GI Infection – anemia, bloody stool (from former attachment sites), abdominal pain
- 17. Ancylostoma caninum Ancylostoma braziliense Ancylostoma caninum Dog hookworm Ancylostoma braziliense Cat hookworm Both cause creeping eruptions
- 19. Infection
- 20. Lab Diagnosis 1. Direct Method: Examination of stool : A macroscopic examination of stool is necessary to find out the adult worms. A microscopical examination of stool may easily demonstrate the presence of characterestic hookworm eggs.
- 21. 2. Study of Duodenal contents: The material obtained by duonenal intubation may sometime reveal either eggs or the adult worms. Indirect methos: Examination of blood: Anaemia,eosinophilia. Occult blood test: positive reaction(charcot- leyden crystals are found in stool.
- 22. Treatment • Albendazole 400 mg orally in a single dose. Or 200 mg in children 1-2 yrs of age. • Mebendazole 100mg orally twice a day for 3 days. • Pyrantal pamoate 11mg/kg to a maximum of 1 gram day for 3 days. • Topical albendazole are useful for creeping eruption. • Iron therapy may be as important as worm eradication..
- 23. Prevention and Control • Sanitary disposal of human faeces • Wearing of footwear • Health education • Treatment of infected individuals
- 24. THANK YOU From : Dr. Saurav Poudel. saurav7utd@hotmail.com (if any query).