Hookworm
🌍 About Hookworm Infection
- Hookworm affects an estimated 576–740 million people worldwide.
- Together with Ascaris and whipworm, it is one of the key soil-transmitted helminths (STH) causing major global morbidity.
- Prevalent in tropical & subtropical regions, especially in areas with poor sanitation and barefoot exposure.
🦠 Aetiology
- Species:
- Ancylostoma duodenale (more pathogenic, higher blood loss per worm).
- Necator americanus (wider global distribution, milder blood loss per worm).
⚙️ Pathophysiology
- Infection occurs when larvae penetrate the skin 👣 (usually bare feet).
- Larvae travel via bloodstream to lungs → cross alveoli → ascend trachea → swallowed.
- They mature in the small intestine → attach to mucosa → suck blood 🩸.
- Adult worms release eggs into faeces → contaminate soil → cycle continues.
- Transmission risk ↑ where people defecate outdoors or use human waste as fertiliser.
🩺 Clinical Features
- Most infections are asymptomatic.
- Symptomatic phases:
- Skin phase: “Ground itch” – itchy rash at entry site.
- Pulmonary phase: Cough, wheeze, eosinophilic pneumonia = Löffler’s syndrome 🫁.
- Intestinal phase:
- Chronic iron-deficiency anaemia → pallor, fatigue, weakness.
- GI upset: abdominal pain, nausea, diarrhoea.
- Severe cases in children → growth stunting, cognitive impairment.
🔬 Investigations
- Stool microscopy: Characteristic hookworm eggs (diagnostic).
- FBC: Microcytic, hypochromic anaemia + eosinophilia (esp. migratory phase).
💊 Management
- Antiparasitic drugs:
- Albendazole 400 mg single dose.
- Mebendazole 100 mg BD × 3 days OR 500 mg single dose.
- Iron supplementation: Correct iron deficiency.
- Dietary advice: Iron-rich foods (meat, beans, green vegetables).
🛡️ Prevention
- Improved sanitation & safe disposal of faeces.
- Encourage wearing footwear 👟 to prevent skin penetration.
- Regular deworming programmes in endemic regions (esp. children & women of reproductive age).
- Community health education on hygiene practices.
🌐 Public Health Impact
- Hookworm contributes to malnutrition, anaemia, impaired growth & cognition in children.
- Mass drug administration (MDA) + sanitation improvements = key WHO strategy for STH control.
📌 Exam Tip
🔑 Triad to remember:
Skin entry (“ground itch”) → Löffler’s syndrome 🫁 → chronic iron-deficiency anaemia 🩸.
👉 Always link hookworm to microcytic anaemia + eosinophilia in exam questions.
