Thank you Nick. A lot of interesting information for an accessible 5-minute read.
As we speak, artesunate still cures over 99.9% of malaria casesāif a little slower than before. But we donāt know when that will become 99%, then only 90% at which point weāll need alternatives.
Iām trying to get my head around the meaning of these numbers. The questions below are largely academic (no goal in mind), surely difficult, and likely dumb, so please feel no pressure to devote valuable time :)
(1)Are these cure rates in reference to the outcome of Therapeutic Efficacy Studies (TES) as described in this WHO document (Section 4.1) and where the outcome is an āadequate clinical and parasitological response (ACPR)ā (p. 11 of that document)?
If it is:
(2) What is your best estimate for how often ACPR would be āachievedā without treatment?* I believe this would be difficult to answer. My estimate right now based off close to zero rationale: 4% (95% CI: 0.25% ā 60%).
(3)What would you estimatethe effect on saving a childās life would be in a drop from 100% to 90%?*Maybe can be quantified as (but you likely have a better way): For every 1000 children who come into a clinic for malaria treatment, how many would survive if (a) artesunate is administered versus if (b) no treatment was provided, given (i) 100% efficacy versus (ii) 90% efficacy.
My suspicion is that the ratio of p(ACPR | artesunate) : p(ACPR | no treatment) underestimates the effect on mortality (and severe malaria) due to the binary outcome measure not capturing benefits from artesunate reducing without eliminating the degree of parasitaemia(?)
Thanks again.
*in high transmission areas where inclusion criteria is āpatients with fever, aged 6ā59 months, with an asexual parasitaemia ranging between 2000 and 200 000 parasites/āĪ¼Lā
1) TO answer this Iām just saying that an artemisin derivative plus another medication (co-artem) will still cure malaria completely almost all of the time, even if it takes longer
I donāt have the answer to 2 or 3 exactly and dontā have the time to look into it but youāre thnking along the right lines. For every 1,000 children who came into a clinic for malaria, at least 950 would survive with no treatment, but even those that survive are likely to encounter a range of problems such as anemia, low energy, recurrent fevers etc. Also like you say people would be more prone to dying from other diseases as well after being weakened from malaria, as is well established in the case of diarrheal disease. Malaria actually weakens immunity directly as well. If I recall correctly somewhere between 1 in 10 and 1 in 20 severe malaria cases has co-infection with a bacterial infection.
Thank you Nick. A lot of interesting information for an accessible 5-minute read.
As we speak, artesunate still cures over 99.9% of malaria casesāif a little slower than before. But we donāt know when that will become 99%, then only 90% at which point weāll need alternatives.
Iām trying to get my head around the meaning of these numbers. The questions below are largely academic (no goal in mind), surely difficult, and likely dumb, so please feel no pressure to devote valuable time :)
(1) Are these cure rates in reference to the outcome of Therapeutic Efficacy Studies (TES) as described in this WHO document (Section 4.1) and where the outcome is an āadequate clinical and parasitological response (ACPR)ā (p. 11 of that document)?
If it is:
(2) What is your best estimate for how often ACPR would be āachievedā without treatment?* I believe this would be difficult to answer. My estimate right now based off close to zero rationale: 4% (95% CI: 0.25% ā 60%).
(3) What would you estimate the effect on saving a childās life would be in a drop from 100% to 90%?* Maybe can be quantified as (but you likely have a better way): For every 1000 children who come into a clinic for malaria treatment, how many would survive if (a) artesunate is administered versus if (b) no treatment was provided, given (i) 100% efficacy versus (ii) 90% efficacy.
My suspicion is that the ratio of p(ACPR | artesunate) : p(ACPR | no treatment) underestimates the effect on mortality (and severe malaria) due to the binary outcome measure not capturing benefits from artesunate reducing without eliminating the degree of parasitaemia(?)
Thanks again.
*in high transmission areas where inclusion criteria is āpatients with fever, aged 6ā59 months, with an asexual parasitaemia ranging between 2000 and 200 000 parasites/āĪ¼Lā
Thanks Scott interesting questions
1) TO answer this Iām just saying that an artemisin derivative plus another medication (co-artem) will still cure malaria completely almost all of the time, even if it takes longer
I donāt have the answer to 2 or 3 exactly and dontā have the time to look into it but youāre thnking along the right lines. For every 1,000 children who came into a clinic for malaria, at least 950 would survive with no treatment, but even those that survive are likely to encounter a range of problems such as anemia, low energy, recurrent fevers etc. Also like you say people would be more prone to dying from other diseases as well after being weakened from malaria, as is well established in the case of diarrheal disease. Malaria actually weakens immunity directly as well. If I recall correctly somewhere between 1 in 10 and 1 in 20 severe malaria cases has co-infection with a bacterial infection.