After artemisinin combination therapy, most falciparum infections clear by day 3. Persisting parasites at that point are the standard clinical marker of possible artemisinin partial resistance — but they can also reflect a high starting parasite load, vomited doses or poor absorption.
So before labelling resistance, confirm the doses were taken with food where advised, ask about vomiting, and compare against the starting count. A falling but positive count on day 3 differs from one that has not moved.
Any rise in parasitaemia, or recurrence within 28 days, is treatment failure and needs a different regimen and specialist input.
- Check doses were taken and kept down before suspecting resistance
- Compare day-3 count with the baseline count, not just positive or negative
- Rising parasitaemia or recurrence within 28 days means treatment failure
- Notify public health when partial resistance is suspected
Why it matters
Distinguishing slow clearance from true failure decides whether the patient needs a different drug.
Read the rest in the app
You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.
Scan to keep reading on your phone. No account needed to start.
Tomorrow morning, before your first patient
One edition a day for infectious diseases, written by the desk, every claim tied to its paper. Six minutes.
Get the app — free