Guinea worm disease reaches all-time low | Hacker News Reader

Guinea worm disease reaches all-time low

cartercenter.org

189 pointsAmorymeltzer66 comments

It's mentioned that "GWD is spread by drinking water containing Guinea worm larvae" (https://www.cdc.gov/parasites/guineaworm/gen_info/faqs.html) but also that "There was no chance for the disease to return after the last human case occurs", how does that fit together? Are people getting it from drinking from the same infected water sources as others, and by not seeing anyone getting it means there is no more infected water sources?

Edit: Apropos nothing, it sounds terrible to get infected:

> Guinea worm disease is usually contracted when people consume water contaminated with tiny crustaceans (called copepods) that eat Guinea worm (Dracunculus medinensis) larvae. The larvae develop into adults within the human host. After about a year, a meter-long pregnant female worm emerges slowly through a painful blister in the skin, often of the legs or feet. A sufferer may seek relief by dipping the affected limb in water. However, contact with water stimulates the emerging worm to release its larvae and start the cycle anew.

Edit: Which, I think answered my question. Leaving my comment rather than deleting it as maybe others had the same question.

I still don't understand how getting rid of the last human case will resolve the issue. Presumably these crustaceans & worms still exist in the wild? Isn't there always a chance for a new flareup to occur?

The parasite only effects humans and dogs. I guess that the worms in the water go away after a while. Prevention breaks the cycle.

The worms themselves don't live in the water at all. Its larvae are released into the water, and can only grow to maturity and reproduce if they're consumed by a host.

And, then consume some of the host (I guess?)

From wikipedia,

"In 2020, Guinea worm was found in 1507 domestic dogs in Chad, 15 in Ethiopia, and eight in Mali, as well as in 61 domestic cats in Chad and three in Ethiopia. Small numbers have also been found in wildcats and baboons.[9] These findings are a potential problem for the eradication program. "

Now I'm making things up, but it may be that eradication from human water sources is enough to break the cycle, if maybe the other mammals in the area are more migratory and cannot provide a consistent reservoir.

As I understand it, they rely on human hosts, so if no humans get infected for a while, the rest will die out. After that, there is none of them left, so no one can get infected again.

It appears to not be known for sure as of 2019 if dogs are a main host or not.

https://www.nature.com/articles/d41586-019-02921-w

The parasite has a life cycle that passes through several stages.

One of the stages involves infecting a mammal (and apparently mostly human) host.

If you disrupt that stage, you disrupt the life cycle of the parasite. If you disrupt that stage completely, no parasite continues to the next cycle and after a bit of time there isn't any more parasite.

The larvae don’t live forever and need a human or dog to procreate.

Also, we’ll only be reasonably sure no human or dog cases exist over a year after the last human was infected because that’s how long it takes for symptoms to become obvious.

I expect the life expectancy of the larvae to be much shorter, but can’t find that online (https://en.wikipedia.org/wiki/Dracunculus_medinensis#Life_cy... says* “Within the copepod, the D. medinensis larvae develop to an infective stage within 14 days”*, but doesn’t mention how long they stay infective or how long they can spend in the water before being eaten by the copepod)

They probably also will be careful of declaring victory too early because of the existence of animal reservoirs (https://en.wikipedia.org/wiki/Dracunculus_medinensis#Animal_...)

It is a cultural thing of educating fisherman to stop feeding fish entrails to dogs, and keeping infected dogs and people from entering the waterways once infected to break the reproductive cycle.

We have an American version of the Guinea work that affects raccoons and other wildlife, but hasn’t crossed over. https://www.michigan.gov/dnr/managing-resources/wildlife/wil...

One phase of the lifecycle only happens in humans and dogs. Once no one (or their dog) has it, then the cycle is done. The out-of-human part is three phases of larva which take a few weeks, although I didn’t see how long the phase 3 larva could persist without a human or dog host to proceed to adulthood.

https://www.cdc.gov/parasites/guineaworm/biology.html

While tragic, it is beyond hilarious that "everyone and their dog" is a thing here.

Love how impactful Former President Carter has been.

I hope he gets to see a year of zero cases before he goes. Quite an accomplishment.

His administration was before my time, but he always seemed like an earnest and levelheaded man.

He also personally repaired a Canadian nuclear reactor in meltdown.

https://www.military.com/history/how-jimmy-carter-saved-cana...

Wow what an interesting story. It's notable that he's still alive at age 99 despite being exposed to dangerously high levels of radiation in his 20s, and a history cancer in the family.

Woah. Repaired it, and had radioactive urine for the next six months. That's... wow. Words fail me.

He spent those months navigating at night by dribbling just a little every few feet.

He was also president during 3 mile island, and helped calm everyone by visiting: https://www.history.com/this-day-in-history/nuclear-accident...

Carter basically stopped the nuclear energy industry by prohibiting reprocessing of used fuel. Without disposal or reprocessing, where does it go?

https://www.pbs.org/wgbh/pages/frontline/shows/reaction/read...

> Carter basically stopped the nuclear energy industry by prohibiting reprocessing of used fuel. Without disposal or reprocessing, where does it go?

This seems like a stretch.

From the article you linked:

Ford initiated the policy a year before Carter signed the EO. While I'm sure some other countries adopted the position due to political pressure from the USA, it doesn't explain why the fission nuclear energy industry everywhere has failed to excel.

The PBS article, written two decades ago, describes an event that's now ~45 years in our past -- but it's not clear why that policy hasn't since been upturned, or what / who is responsible for its continuation (other than the tritely obvious answer 'every USA administration since then').

> it doesn't explain why the fission nuclear energy industry everywhere has failed to excel.

Isn’t French nuclear powering 70% of all their needs?

are they reprocessing spent fuel? That seemed to be the crux of the parent comment.

They have nearly half of the worlds reprocessing capacity in their plant in La Hague https://en.m.wikipedia.org/wiki/La_Hague_site

And how much energy does the fuel coming from that plant produce each year as a fraction of the whole?

Net energy might be a better measure - a plant could produce a huge amount of energy from reprocessed fuel, but if it costs more energy to rerefine the fuel than mine similar fuel from rock formations...

Sure, everyone points to France when talking about nuclear fission - adoption, abandonment, success, failure - taken over the past 50 years they've got it all.

France would have been subject to pressure from the USA at the time, so it's certainly a notable anomaly from this angle, as well as several others.

I think this makes it an interesting case study, but doesn't (given it's such an exceptional example) explain the phenomenon we're talking about.

On the global scale, nuclear waste is a minuscule problem. Orders of magnitude smaller than iron production waste. So despite the high cost of nuclear waste storage per kilogram, the total cost is actually minuscule.

For an average American's final energy usage you'd need 2kg of Uranium per year transported and stored in 5kg of copper and steel cask encased in 20kg of concrete. Dealing with this is significantly more dangerous and destructive than the 250-500kg of iron ore per person per year.

And leaching it in a mine with median grade uses about 200kg of sulfuric acid each year to process 7 tonnes of heavy metal containing ores.

The only reason it's 'miniscule' is most of the problem is out sourced to kazakhstan, uzbekistan, nigeria, namibia, and australia. And around 3% of final energy is provided by nuclear.

Can I see how you got that Uranium figure? Because raw Uranium doesn't need that sort of treatment (it's not radioactive enough) and I'm struggling to believe 2kg of refined Uranium is needed per person per year to meetb3% of energy need.

DU is still a toxic heavy metal, and the 3-15% by mass (or 100% in a HWR) that becomes SNF needs containment that outmasses it by at least an order of magnitude.

Then there's another order of magnitude more LLW again.

> to meet 3% of energy need

This is disingenuous because the proposition is to expand it to make a relevant contribution to decarbonization.

> On the global scale, nuclear waste is a minuscule problem. Orders of magnitude smaller than iron production waste.

At least the waste from iron production doesn't need to be locked away for millennia safe enough that it doesn't pose a danger to people.

Arguably, sequestering all that CO2 for ten thousand years sounds like a great idea!

7% of global emissions.

https://www.iea.org/reports/iron-and-steel-technology-roadma...

That's already included in the cost. Still minuscule.

Reprocessing doesn't get rid of anything other than the tiny fraction which is Pu239. It also dilutes the waste making it much harder to handle and spreads it all over the place.

Carter wasn't single handedly responsible for every reprocessing facility on the planet turning into a radiation ridden money pit.

The UK reprocessing at Windscale/Sellafield seems to have been an engineering success but a commercial failure. https://www.world-nuclear-news.org/Articles/Sellafield-ends-...

It spread fission products everywhere, leaked many times more Cs137 than Fukushima, the site will cost many billions to clean despite only reprocessing enough to run a couple of reactors, the sediments it ejected into will never be clean, and it didn't get rid of any meaningful amount of Pu241, Pu240, Am241, Cm, Np or fission products. The fuel it produced was far more expensive than fresh, and it didn't obviate the need to dig up Uranium.

Reprocessing achieves nothing other than PR and making bombs (even the 'processing weapons plutonium' is just a PR exercise because the plutonium 'disposed of' had too much Pu241 decay into Am to stay in the warhead anyway).

In some iraqui oasis, people forget about president bush already, but the absence of this worm, will never be forgotten...

Good deeds conquer the world, conquerors are just a seasonal redecoration blown away with time..

>In some iraqui oasis, people forget about president bush already

Sure they don't forgot the 275'000 death's?

4,424 soldiers died.. thats one american being worth 62 iraquis.

One village killed for every soldier lost. They were not this draconion in the medieval ages. What a disgusting evil, murderous & godless monstrosity of an empire.

Compare that to military civilian death rates in world war 2, with 25 million military deaths and 55 million civilian deaths. If were not for those alibi deaths, we would call it a mass execution.

Well yes you are totally right...and that's what i try to say (that the people for sure not forgot bush's actions).

I had thought Bill and Melinda Gates played a significant role in this.

If you are curious and have the stomach to watch, there's plenty of youtube videos like this one [0] to give you an idea of what actually being infected looks like.

[0]: https://www.youtube.com/watch?v=oCB1A2gFvuU

Is anyone doing anything to save the endangered Guinea Worm? Do we have DNA sequences, freeze-dried and fossilized remains, chemical analysis? Have we tested the viability of reviving eggs after a few years frozen?

It's a terrible disease and I don't want anyone to ever get it again... but I'm something of a pessimist in terms of how eradicated we can make it, and believe there's probably still something to be learned from the methods by which it infects hosts - How it evades detection, stifles the body's immune system, or whatever. There is probably value in keeping a population around even once it's eliminated in the wild, for research and study... Though whether it's worth the time, effort, and risk is a question for epidemiologists, not me.

Seems less risky than, say, keeping smallpox samples, or doing gain-of-function research on coronaviruses.

After many decades of study by a huge number of scientists, I suspect there is probably little left to be learned. It's probably more likely that keeping specimens around would lead to the development of biological weapons than anything else, I'd think. We surely have the genes sequenced, that's a very safe way to study the worm without risking the mishandling of a live specimen.

As a biological weapon, the Guinea worm leaves much to be desired.

This is the kind of thinking that brought the world to it's knees in 2020.

As a wise woman said:

> I say we take off and nuke the entire site from orbit. It’s the only way to be sure.

It's a parasitic nematode, there are many of them. Just study the others. Looking at wikipedia, this one is quite similar https://en.wikipedia.org/wiki/Anguillicoloides_crassus but it infects eels instead of humans.

People are responding to you snarkily, but there's real value in preserving every species that exists, including gain-of-function research (Assuming it isn't conducted by idiots, no malicious motivations in the people conducting the research, and isn't kept in secrecy). The worms may be symbiotically beneficial to humans in some unknown, complex way, or could possess unique biological processes/elements that could be of medical significance. Additionally, having their genetic information in a large database WILL provide useful general biological and evolutionary information.

> Assuming it isn't conducted by idiots, no malicious motivations in the people conducting the research, and isn't kept in secrecy

With those assumptions, many more things would be fine!

I read that when they took the last wild condors into captivity they thoughtlessly deloused them without any thought that their lice would be of any interest.

If you don't think it can be eradicated, actively preserving it seems pointless?

There are these guys: http://www.deadlysins.com/guinea-worm

(I agree with you, I hope they froze some, or at least sequenced the DNA.)

There are those who believe Jimmy Carter's efforts to eradicate this disease make him the greatest living ex-president by a wide margin.

I recently heard of the theory that a lot of contemporary stomach issues are due to the reduced worm diseases. The theory goes that our immune system evolved in a context of much more stomach parasites and adapted accordingly. Today it is 'bored'.

I don't think there are worms that live in stomachs.

Not in the stomach, but tapeworms live in the intestines.

This is known as the hygiene hypothesis.[1]

[1] https://www.broadinstitute.org/news/8131

N == 1, my mother loves cleanliness and I lived in a very clean environment when I was a kid. I was also sick all the damn time.

Once I went away from home at 18, my natural slobbiness prevailed. I am not a horrible pig, but nowhere near as keen on washing hands or fruit or wearing freshly pressed clothes as my mom is. And my immunity started improving visibly.

As of now, I am 44 y.o. I almost never get sick, and if I do, it rarely lasts more than two days. I haven't had antibiotics prescribed since 2012 I think. If something itches in my throat, I flush my nose with salty/mineral water and the problem goes very reliably away.

Even most of my alergies just went away, with the weird exception of cat allergy that I acquired in adult age.

This is frequent, be glad you don't have lasting allergy issues like many do after being raised by 'germ freaks' to be impolite (its hard for me to be polite when parents damage lives and health of their kids with some fanatical zeal).

I know few cases which are left with reduced quality of life (and probably length too) due to this, no matter what they try to overcome this.

"its hard for me to be polite when parents damage lives and health of their kids with some fanatical zeal"

To be honest, my mom raised me in the early 1980s, when the knowledge about risks of cleanliness was simply not there, especially not in popular science sources available behind the Iron Curtain.

Nowadays, I am much more respectful about the need to interact with various germs, commensal and symbiotic microbiota, but I have the advantage of having Internet at my disposal. Even so, it is not easy to strike the right balance. Germs may be good for you, but various chemicals used in agriculture definitely aren't and try getting rid of one while keeping the other intact. (Organic produce helps, but it is expensive to boot.)

Beautifully even handed comment.

Its not about 'risk of cleanliness' that I was talking about, I've been raised also behind Iron curtain during same period in your neighboring state. Nobody back then was saying absolute cleanliness was a way to go. Normal kind of approach had very mild side effects if any and ie kids cleaning their hands or face is overall not a bad approach and agreed upon even today.

I really meant some form of fanatical approach to it, which is never a good approach for anything. One didn't need internet for such common sense wisdom (aka middle path is practically always the best approach regardless of topic).

But surprisingly high proportion of population suffers from some form of germophobia, so maybe that's what you meant. Without any scientific feedback on good aspects of having them around, I guess some folks went a bit banana with that (since you can never clean way all the bacteria in common household due to their sheer numbers overcoming any approach, so people affected by it can escalate hygiene to extremes)

Reply on news.ycombinator.com