How would you run the statistics on whether Ivermectin helped India reduce COVID-19 cases?
post by ChristianKl · 2021-07-03T16:09:17.991Z · LW · GW · 6 commentsThis is a question post.
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Answers 2 ndr None 6 comments
I frequently read the claim that India reduced their COVID-19 cases a lot via Ivermectin but it's very unclear to me whether the relevant data to make that claim is cheripicked.
India has 34 region and each of those region has their own policy on Ivermectin. While we don't have exact data about Ivermectin usage, Google Trend data provides a proxy for usage of Ivermectin and does provide data that's fine-grained enough to separate individual region. John Hopkins provides data for COVID-19 cases by Indian region as well. 34 regions sounds to me like it's plausible to find statistically significant results if Ivermectin had an effect that's as great as proponent of Ivermectin claim
Given p-hacking concerns, it makes sense to first decide on how to analyse the data and then run the statistics. Does anyone have suggestion for how the data should be analysed?
Answers
India's situation is messy because of the different states policies.
To properly do this one would need to control for incidence and lockdown policy state-by-state. Also some states have no approval for Ivermectin yet it gets used.
My best bet is that we'll get the cleaner data on whether it works from Europe, in particular from Slovakia and Czechia.
Even if EMA advises against Ivermectin, Slovakia approved it for both prophylaxis and treatment in late January 2021.
I could not find how widespread the slovak usage of Ivermectin is, but there are few points:
- Mobility report shows that Slovakia is not locking down, not effectively at least
- Bratislava airport has arrivals from all places (including UK), seemingly no closed borders
- Less than <40% of Slovakia population is vaccinated (vs >65% in UK, 47% in CZ)
- Cases in Slovakia keep going down, but Czechia seems to start going up
I've not found data on the delta variant incidence in Slovakia, maybe it didn't reach there yet. It's 98% of cases in UK, 30% in CZ.
If Slovakia sees a ramp up in delta cases the Ivermectin proponents will likely say it wasn't used enough/correctly, and the detractors will keep saying it was useless from the start.
On the other hand, if Slovakia does not see a ramp up in delta cases whilst keeping a low vaccination rate and no effective lockdown in place it'd suggest something else must be at work.
Saying it's Ivermectin will come off as reasoning from exclusion but it'd be my best-bet hypothesis.
↑ comment by ChristianKl · 2021-07-04T17:34:34.480Z · LW(p) · GW(p)
https://www.statista.com/statistics/1245971/number-delta-variant-worldwide-by-country/ has data as of two days ago and shows 6 cases of delta for Slovakia.
Replies from: ndr6 comments
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comment by Lukas_Gloor · 2021-07-03T19:42:47.167Z · LW(p) · GW(p)
I know this isn't answering your question, but how could this claim possibly make any sense? To slow the country-wide transmission rate substantially with a prophylactic intervention, wouldn't you have to give it to similarly many people as you give vaccines? And given that India isn't among the countries with the largest vaccination percentages, it's unlikely it was able to distribute a potential prophylactic to a substantial percentage of its population. Or did it? And as a treatment post illness – well, that also doesn't make sense because most people who infect others do so before getting diagnosed by a doctor.
I feel like the people who make this claim about India and ivermectin are confusedly trying to explain something that doesn't need explaining. Why didn't the Delta variant overwhelm India completely? Because of the control system. We've seen this every time a new variant emerged. Massive spike, then people get scared and the numbers go down. I even noted this in advance [LW(p) · GW(p)]. There doesn't need to be a further explanation. Pinning it on medicine just seems like the typical bad reasoning of people who think they found a miracle cure for everything. (Not saying ivermectin is useless; I actually know absolutely nothing about it and don't have an opinion. And if it somehow does turn out that ivermectin plausibly contributed to keeping India's case load measurably lower, then I'll eat a piece of cardboard, or something.)
↑ comment by ChristianKl · 2021-07-03T21:17:36.163Z · LW(p) · GW(p)
I know this isn't answering your question, but how could this claim possibly make any sense? To slow the country-wide transmission rate substantially with a prophylactic intervention, wouldn't you have to give it to similarly many people as you give vaccines?
They did give it prophylactically to a lot of people. In Goa they prescribed it to all people over 18. According to Google the COVID-19 case rate peaked in Goa on May 11, 2021 which is a day after the decision to give out ivermectin prophylactically. I would guess that everybody in Goa who has access to COVID-19 testing also has access to ivermectin.
After the state Congress chief of Goa Girish Chodankar tweeted on May 23, 2021 that giving out ivermectin prophylactically is a scam you get a short spike up again in the COVID-19 data. This is an anecdote and not proof, but it's a good anecdote. People frequently argue that government policy on issue X worked frequently with worse data.
Uttarakhand decided a day later then Goa to give out ivermectin and also had a day after their anouncement their peak according to the Google data.
If you believe the case number to be real and not faked to make ivermectin look good this is a huge coindidence. It's also a bit odd that the efffect is immediately after the anouncement.
Replies from: Lukas_Gloor↑ comment by Lukas_Gloor · 2021-07-04T04:41:04.293Z · LW(p) · GW(p)
Thanks for explaining, that sounds interesting. I remain skeptical about the numbers, though, because (a) it just seems so odd that a country with 4% vaccination percentage now distributed something useful successfully to enough people to significantly reduce spread, and (b) the timing sounds too coincidental to me, and not very plausible. But there's maybe a >1% chance that there's something interesting going on here. :)
Replies from: ChristianKl↑ comment by ChristianKl · 2021-07-04T12:37:25.272Z · LW(p) · GW(p)
I think the vaccination rate is mainly low because of supply issues with the vaccine. On the other hand ivermectin is easier to produce and given that it was used for treatment before that point pharmacies likely had stocked it.
People in remote villages without any access to vaccines or ivermectin likely won't get COVID-19 test, so I expect them to not be in the offical case count. The case count is likely only counting those that have access to the medical system.
A recent meta analysis found 'Low-certainty evidence found that ivermectin prophylaxis reduced COVID-19 infection by an average 86% (95% confidence interval 79%–91%).'
If ivermectin did have that effect, it's plausible that you see immediate effects on the case rate. Currently, we only have that low-certainty evidence from trials and the case studies from India I spoke about above, so I don't have any certainty that this is what actually happens.
Given that the reduction of 86% through ivermectin would likely be independent of vaccines, common knowledge that ivermectin works might allow us to easily drive SARS-CoV-2 to exstintion if it works.
There were calls in 2018 to investigate repurposing Ivermectin for influenza. The best case scenario would be that it works prophylactically against flu as well and we get rid of flu while we are at it.
There's a lot of uncertainty here, but there the potential of a lot of value to be gained, so the value of information is very high.
↑ comment by Louisa Clary (louisa-clary) · 2021-07-03T21:13:53.374Z · LW(p) · GW(p)
India was way ahead of the game initially. It was government issued last August. As in every single person who got sick got it. Doctor came to your house and then gave it to everyone as a prophylaxis that was in the house in addition to the one that was sick.
An Unlikely Nation: https://tinyurl.com/10vrvdr1
Here is how it worked if someone got sick: Visitor to India gets C-19: https://tinyurl.com/35eycjbk
Full timeline of how India won the battle against C-19 and then the second wave hit and why it struggled but now has beat the US in deaths per population as of a few days ago... https://threadreaderapp.com/thread/1394980291249385475.html
Replies from: louisa-clary↑ comment by Louisa Clary (louisa-clary) · 2021-07-03T21:38:33.290Z · LW(p) · GW(p)
The issue is, you won't hear about this from mainstream media. It is very weird and fascist-like honestly. The censorship is crazy. The discoverer of Ivermectin, Professor Satoshi Omura who won the Nobel Peace prize for Ivermectin ---and it was also added to the WHO's list of essential medicines---he was deleted off of YouTube yesterday and he wasn't even telling anyone to ingest anything.
Reuters Chair of the Board is also on Pfizer's Board of Directors. Dr. Scott Gottlieb on MSNBC informing everyone he knows to take the vac, is also on Pfizer's Board of Directors. I have been told (not yet verified) that in the States every single network has a pharma board member on it except for CBS. I would like to dig on that one.
And the rest of the media and big tech are all in the alliance for one agenda signed onto December 2020---called the "Trusted" News Initiative ---Including the BBC, Reuters, a full list of media, Google, Facebook, YouTube and more. Here is a Twitter thread showing the full list. So none of them will report the truth about early treatment. https://twitter.com/louisaclary/status/1397251241793699847?s=21
One journalist broke from her network and came out with this. She could never do it with the network so she walked. Most truth I have ever seen on Ivermectin and HCQ from a doctor who has done over 1600 interviews for his work on C-19 at his hospital in Houston. His hospitals' death rate was 6% while the nations' average was over 20%. This was incredible and it took the last 16 months for it to finally come out: https://t.co/1XHZYrtGHy