🦟 Malaria Treatment Hero 🏥
Learn how to diagnose and treat malaria while saving lives!
Welcome, Doctor! You're in a malaria-endemic region and patients need your help.
Make the right decisions to diagnose and treat malaria effectively!
📚 Malaria Study Guide (SFM Class Material)
What is Malaria?
Malaria is a protozoa transmitted by night-biting female Anopheles mosquitoes. Can also be transmitted by transfusion, needlesticks, transplantation, or mother to child. Only 5 of 100 Plasmodium species infect humans.
Malaria Species
- P. falciparum (Pf): Worldwide. No hypnozoites. Most severe due to SEQUESTRATION in visceral capillaries (brain, heart, placenta). Invades all RBC ages. Normal size RBCs with multiple small rings on smear.
- P. vivax (Pv): Latin America, Asia, Middle East, Africa. Has HYPNOZOITES (dormant liver stage) → relapses. Only invades reticulocytes. Enlarged, misshapen RBCs on smear.
- P. ovale (Po): Central-West Africa only. Has hypnozoites. Only invades reticulocytes. Enlarged, oval, "comet forms" on smear.
- P. malariae (Pm): Limited distribution. No hypnozoites. Only invades senescent RBCs. Mildest form. Band forms on smear.
- P. knowlesi (Pk): SE Asia. No hypnozoites. Can be mild to very severe.
Key Concept: HYPNOZOITES
P. vivax and P. ovale ONLY: Dormant liver stages that reactivate weeks to years later causing RELAPSES. This is why radical cure with primaquine (after G6PD check!) or tafenoquine is essential.
Diagnosis
- THICK smears: More sensitive for detecting parasites
- THIN smears: Discriminate between species
- RDTs: Rapid antigen tests (useful in resource-limited areas)
- PCR: Available at CDC (not first-line due to cost/time)
- Repeat smears if negative but high suspicion!
Treatment: Clinical vs Radical Cure
- Clinical Cure: Eradication of RBC trophozoites and schizonts
- Radical Cure: Also eradicating hepatic hypnozoites (Pv/Po)
Severe vs Uncomplicated Malaria
Severe malaria (>20% mortality): Impaired consciousness/coma, seizures, respiratory failure/ARDS, renal failure, shock, severe hypoglycemia, acidosis. Requires ICU care + IV artesunate.
Uncomplicated: Fever, chills, headache, myalgias without organ dysfunction. Oral ACT appropriate.
Key Medications
- IV Artesunate: First-line for SEVERE malaria (+ second agent)
- Artemether-lumefantrine: Fixed-dose ACT for uncomplicated Pf
- Atovaquone/proguanil: Prophylaxis (daily) and treatment
- Primaquine: For HYPNOZOITES (Pv/Po). CHECK G6PD FIRST! Contraindicated in pregnancy
- Tafenoquine: Prophylaxis and radical cure. Also needs G6PD check
- Mefloquine: Prophylaxis (weekly). Neuropsychiatric side effects
- Doxycycline/Clindamycin: Used in combination
CRITICAL: G6PD Deficiency
MUST check G6PD before primaquine or tafenoquine - causes ACUTE HEMOLYSIS if deficient! Also contraindicated in pregnancy (unknown fetal G6PD status).
Why Combination Therapy?
- Kill parasites by multiple mechanisms
- PREVENT RESISTANCE development
- Artemisinin derivatives must be combined with another agent
Prophylaxis
Take BEFORE, DURING, and AFTER exposure:
- Atovaquone/proguanil: Daily, 7 days after
- Doxycycline: Daily, 28 days after
- Mefloquine: Weekly, 4 weeks after