A 32-year-old woman from rural Odisha presents with fever, chills, and sweating for 3 days. She reports the fever occurs every alternate day, with temperatures reaching 40°C. On examination, she is pale with mild splenomegaly. A blood smear taken during the fever spike shows ring forms and Schüffner's stippling. She has no history of antimalarial prophylaxis. What is the most appropriate first-line antimalarial regimen for this patient according to NVBDCP guidelines?

Explanation

## Clinical Presentation Analysis The patient presents with: - **Fever pattern:** Tertian (every 48 hours) — characteristic of *Plasmodium vivax* or *P. ovale* - **Blood smear findings:** Ring forms with Schüffner's stippling — pathognomonic for *P. vivax* - **Geography:** Rural Odisha — endemic zone for vivax malaria - **Severity:** Uncomplicated malaria (no altered sensorium, no organ dysfunction, no severe anaemia) ## NVBDCP Treatment Algorithm for Uncomplicated P. vivax Malaria **Key Point:** According to NVBDCP (National Vector Borne Disease Control Programme) guidelines, **chloroquine remains the first-line treatment for uncomplicated *P. vivax* malaria in India**, given as: - **Day 1:** Chloroquine 600 mg base (10 mg/kg) - **Day 2:** Chloroquine 300 mg base (5 mg/kg) - **Day 3:** Chloroquine 300 mg base (5 mg/kg) - **Total dose:** 1500 mg base over 3 days This is followed by **Primaquine 0.25 mg/kg/day for 14 days** to eliminate hypnozoites and prevent relapse (after G6PD screening). **High-Yield:** While chloroquine-resistant *P. vivax* exists in some parts of the world (Papua New Guinea, Indonesia), NVBDCP guidelines for India continue to recommend chloroquine as first-line for uncomplicated vivax malaria. Artesunate IV/IM is reserved for **severe/complicated malaria**, not uncomplicated cases. ## Why Chloroquine (Option C) is Correct - This patient has **uncomplicated *P. vivax* malaria** — no features of severity (no cerebral malaria, no renal failure, no severe anaemia, no respiratory distress) - NVBDCP 2019/2023 guidelines: Chloroquine 25 mg base/kg over 3 days is the standard first-line regimen for uncomplicated vivax malaria in India - Chloroquine acts by inhibiting haem polymerisation in the parasite's food vacuole, leading to toxic haem accumulation - After chloroquine, primaquine is added for radical cure (anti-hypnozoite activity) **Clinical Pearl:** Schüffner's stippling is visible in *P. vivax* and *P. ovale* RBCs under Giemsa stain. Its presence confirms vivax/ovale malaria and mandates primaquine therapy (after G6PD testing) to prevent relapse from dormant liver-stage hypnozoites. ## Rationale Against Other Options | Option | Why Wrong | |--------|-----------| | Artemether 80 mg IM (Option A) | Artemether IM is used for severe malaria when IV access is unavailable. The dosing schedule given (80 mg day 1, then 40 mg daily × 6 days) is non-standard. Not indicated for uncomplicated vivax. | | Quinine 600 mg IV 8-hourly (Option B) | Quinine IV is reserved for severe/complicated malaria or when artesunate is unavailable. It carries risks of hypoglycaemia, cinchonism, and cardiac arrhythmias. Not first-line for uncomplicated vivax. | | Artesunate 2 mg/kg IV (Option D) | IV/IM artesunate is the WHO/NVBDCP recommendation for **severe malaria** (any species). This patient has uncomplicated malaria; parenteral artesunate is not indicated. | **Mnemonic:** **CQ for VQ** — **C**hloroquine for uncomplicated **V**ivax (then add Prima**Q**uine for radical cure). *Reference: NVBDCP Guidelines for Diagnosis and Treatment of Malaria in India; Park's Textbook of Preventive and Social Medicine, 26th edition.*