“For most highly malarial countries that I checked, the YLD per affected person per year through malaria are around 0.018 while the YLL per affected (dead) person per year are 1. So it seems that being dead is 50 times worse than suffering from malaria.” No I think you misunderstood. The primary reason the YLD per affected person per year is so low is because a case of malaria generally last significantly less than 1 month, so an “affected person with malaria” will actually not have malaria for most of the year.
When I was researching the disability weight of dengue, yellow fever etc., for the Oxitec policy comment, the disability weights tended to be in the .7-.8 region per duration of suffering from those illnesses (ie, worse than clinical depression, which was surprising to me). Because the symptoms of most mosquito-borne illnesses seem to be quite similar, I suspect that malaria will also have a similar disability weight. So dying is probably no more than 2x as bad as suffering from malaria.
Another point to note is that most people who get malaria don’t die. Extrapolating from WHO statistics*, there is roughly one death from malaria every 500 cases! Nonetheless, i believe the median GW employee estimates that the morbidity-impact of malaria prevented through LLINs is about 50% that of the mortality-impact. So unless I’m misunderstanding something (maybe AMF distributes to high-mortality regions or demographics), 1 death is roughly as bad as 1000 cases of non-fatal malaria averted, mostly because of large differences in duration.
So that is probably the range where the weighed average should end up too.
These were derived using a combination of two elicitation methods that eventually scale the results to the [0, 1] interval: “The surveys used paired comparison questions, in which respondents considered two hypothetical individuals with different, randomly selected health states and indicated which person they regarded as healthier. The web survey added questions about population health equivalence, which compared the overall health benefits of different life-saving or disease-prevention programmes. We analysed paired comparison responses with probit regression analysis on all 220 unique states in the study. We used results from the population health equivalence responses to anchor the results from the paired comparisons on the disability weight scale from 0 (implying no loss of health) to 1 (implying a health loss equivalent to death).”
I’ve corrected my Guesstimate accordingly. A duration of 2–8 weeks puts the disability weights roughly in that area, but I haven’t found any data on the duration distribution of malaria episodes. (The much larger number of nonlethal episodes is something I already took into account.)
“So dying is probably no more than 2x as bad as suffering from malaria”: But per year, right? Death lasts much longer than a year for most people who die of malaria according to the system. Some 78 years using the Japanese life expectancy at birth and just a decade or two less using sub-Saharan African life expectancies. That’s in the context of the first paragraph, though, which you maybe didn’t even mean to comment on.
Somewhat tangential, but:
“For most highly malarial countries that I checked, the YLD per affected person per year through malaria are around 0.018 while the YLL per affected (dead) person per year are 1. So it seems that being dead is 50 times worse than suffering from malaria.” No I think you misunderstood. The primary reason the YLD per affected person per year is so low is because a case of malaria generally last significantly less than 1 month, so an “affected person with malaria” will actually not have malaria for most of the year.
When I was researching the disability weight of dengue, yellow fever etc., for the Oxitec policy comment, the disability weights tended to be in the .7-.8 region per duration of suffering from those illnesses (ie, worse than clinical depression, which was surprising to me). Because the symptoms of most mosquito-borne illnesses seem to be quite similar, I suspect that malaria will also have a similar disability weight. So dying is probably no more than 2x as bad as suffering from malaria.
Another point to note is that most people who get malaria don’t die. Extrapolating from WHO statistics*, there is roughly one death from malaria every 500 cases! Nonetheless, i believe the median GW employee estimates that the morbidity-impact of malaria prevented through LLINs is about 50% that of the mortality-impact. So unless I’m misunderstanding something (maybe AMF distributes to high-mortality regions or demographics), 1 death is roughly as bad as 1000 cases of non-fatal malaria averted, mostly because of large differences in duration.
http://www.who.int/features/factfiles/malaria/en/
Oh, I see. Thanks! Here is a study that seems to use two of the following disability weights for malaria from this one:
Infectious disease: acute episode, mild 0.005 (0.002–0.011)
Infectious disease: acute episode, moderate 0.053 (0.033–0.081)
Infectious disease: acute episode, severe 0.210 (0.139–0.298)
Infectious disease: post-acute consequences (fatigue, emotional lability, insomnia) 0.254 (0.170–0.355)
So that is probably the range where the weighed average should end up too.
These were derived using a combination of two elicitation methods that eventually scale the results to the [0, 1] interval: “The surveys used paired comparison questions, in which respondents considered two hypothetical individuals with different, randomly selected health states and indicated which person they regarded as healthier. The web survey added questions about population health equivalence, which compared the overall health benefits of different life-saving or disease-prevention programmes. We analysed paired comparison responses with probit regression analysis on all 220 unique states in the study. We used results from the population health equivalence responses to anchor the results from the paired comparisons on the disability weight scale from 0 (implying no loss of health) to 1 (implying a health loss equivalent to death).”
I’ve corrected my Guesstimate accordingly. A duration of 2–8 weeks puts the disability weights roughly in that area, but I haven’t found any data on the duration distribution of malaria episodes. (The much larger number of nonlethal episodes is something I already took into account.)
“So dying is probably no more than 2x as bad as suffering from malaria”: But per year, right? Death lasts much longer than a year for most people who die of malaria according to the system. Some 78 years using the Japanese life expectancy at birth and just a decade or two less using sub-Saharan African life expectancies. That’s in the context of the first paragraph, though, which you maybe didn’t even mean to comment on.