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The Catalog of Eradicated Diseases Is Brief—At Best

Even without anti-vaxxers, keeping diseases down is hard.

​​The resurgence of measles across large swaths of United States is a certain kind of dystopia. A world manages to rid itself of a sometimes deadly, more often disabling—at the very least agonizing—disease that was once a grim and mostly untreatable fact of life and, rather than relishing a world with a bit less misery, its citizens turn on the vaccine itself, like an overdriven immune system turning on its host.

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Like climate change denial, the anti-vax movement is mostly self-refuting —or, if it wasn't before, it certainly is now (one would hope). But it gives us an opportunity to talk about eradication in general, which happens to be one of the more fascinating features/accomplishments of evidence-based medicine. Eradication is where a vaccine becomes a de facto cure.

Since 1798, when Edward Jenner demonstrated the effectiveness of the first smallpox vaccine, medicine has been in a slow-motion war of geoeradication. Make no mistake: This is the brutal kind of war, the sort fought from trenches and one that lingers well after everyone should be beaten just to draw the horror out. To date, there are only two diseases that can be said to have been fully eradicated, and just a small handful of others that are just partially eradicated.

Image: Wiki

Smallpox

Status: Eradicated 

Last case: 1977, Somalia 

Lives saved: ​5 million annually

Edward Jenner's smallpox vaccine was hardly pleasant. It was the product of material (pus) oozed out of lesions caused by cowpox, a milder and zoonotic form of smallpox. It would have been injected using the syringe technology of the time, probably via a needle made from glass or silver about a quarter-inch in thickness. Some degree of viral infection would occur, but in return the patient would get immunity and relative safety.

Smallpox remains a concern primarily because the United States and Russia are believed to both have some of the stuff stashed away for bioweapons research, even though that seems pretty dangerous. Like nuclear weapons.

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Image: Wikimedia

Rinderpest

Status: Eradicated

Last case: 2001 

Fatality rate: 95 percent

​Rinderpest, caused by a virus similar to the one behind measles, was an epizoonotic disease, infecting mostly cattle and wildlife. It was super-deadly, with most infected animals dying about a week into the illness. It would kill an average of 95 percent of animals within an infected herd.

Many millions of cows and other animals died during African outbreaks in the 1980s, which spurred the Pan-African Rinderpest Campaign of surveillance and vaccination. The program was mostly successful, wiping the virus out in most countries, save for Somalia. The 1994 Global Rinderpest Eradication Programme  ​finished the job.

In all, the eradication effort cost around $5 billion. If that figure seems high, consider that the first, 1980s effort boasted a cost-benefit ratio of 1:85. For every dollar spent, 85 dollars were saved or recovered.

See also:  ​Distemper.

Measles

Status: Eradication stalled

Last case: ​DisneyLand, 50 cases

Lives saved: 2.7 million annually

Yep. Here we are. Measles, a brutal and complication-prone (read: deadly) viral infection, was declared eliminated in the United States in 2000, which was the end result of a goal set in 1994 by the countries of North and South America.

Europe has had more trouble in its measles eradication quest. The anti-vax movement has burned even more hotly in certain regions of the continent, in some significant part keeping Europe from its own 2010 elimination goal. It's since been revised to 2015, while European nations experience similar small but profound regional outbreaks to the one currently underway in California. Mostly, however, it seems that the anti-vax movement has only dug in deeper. Great job, nice work.

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See also:  ​Rubella.

Image:  PD-USGOV-HHS-CDC​

Onchocerciasis

Status: Eradicated only in Columbia 

Last case: most anywhere in tropical Central and South America, along with parts of Africa.

Blind: 270,000

Visually impaired: 800,000

Parasitic diseases are their own special kind of problem. For one thing, they happen because of sinister worms, which are not very much like the phages we're used to, i.e. viruses and bacteria. These are entire organisms, organized systems that grow and devour. They're also some of the most resilient lifeforms known to humans. The millimeter-long nematode Caenorhabditis elegans was the only living thing to survive the space shuttle Columbia disaster, to give some idea.

They're also uniquely challenging because of where they come from, which is dirty water. And if ever there was a marker of poverty, it's dirty water. It becomes inescapable, a fact of life. Which makes parasitic infections like Onchocerciasis, commonly known as river blindness, a fact of life as well.

River blindness comes from black flies, which breed around untreated water sources, hence the name. Once a human is infected, the parasite moves onward to the skin, where it becomes transmissible to the next black fly that bites the host. The cycle continues. And, yeah, the larval nematodes are known to emerge (from the skin) at this point, which is entirely fucked up and I'm sorry.

There is no vaccine, only a treatment that kills Onchocerciasis larvae. So, to get ahead of the thing will require treating enough people (and in some cases water) to eliminate the infection's transmission vector, e.g. conferring herd immunity.

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In 2013, Columbia was declared to be the first country to have successfully eradicated the disease. Numerous programs designed to treat infected residents are ongoing (again, treatment as prevention), and the first vaccine is now in the trial stages, but only for cows.

See also: Malaria,  ​Guinea Worm Disease​Hookworm.

Image:  PDB1DGI​

Polio

Status: Eradicated everywhere but Africa and the Middle-East

Last case: N/A

Lives saved: 640,000 annually

The grand mother of them all, the case that proved modern medicine itself (kind of): ending polio. Except not quite. The infection, a virus spread mostly via feces, still persists in reasonably small quantities as localized outbreaks across Asia and endemically in Pakistan, Nigeria, and Afghanistan.

The past couple of years have seen an alarming (and very sad) resurgence of the virus in Syria, the result of declines in safe-water sources and overall sanitation in the wartorn country. This plus outbreaks in Somalia, Kenya, and Ethiopia led to the declaration of a  ​world health emergency by the WHO in 2014.