DNA Confirms Cause of 1665 London's Great Plague (bbc.com)

← Back to Stories (view on slashdot.org)

DNA Confirms Cause of 1665 London's Great Plague (bbc.com)

Posted by EditorDavid on Saturday September 10, 2016 @07:34PM from the all-fall-down dept.

Slashdot reader JThaddeus writes: The BBC reports that a 17th-century mass grave uncovered in London confirms the identity of the bacteria responsible for the Great Plague of 1665-1666. "Testing in Germany confirmed the presence of DNA from the Yersinia pestis bacterium -- the agent that causes bubonic plague -- rather than another pathogen." The grave contains approximately 3,500 skeletons... Teeth were removed from some of the skulls, and their pulp tested at the Max Planck Institute in Germany. Positive results were found in 5 of 20 individuals tested.
"To reassure anyone worried whether plague bacterium was released from the excavation work or scientific analysis, it doesn't survive in the ground," reports the BBC. The 3,500 graves represent roughly 3.5% of London's 100,000 victims of the Great Plague -- one-quarter of the city's entire population.

51 of 77 comments (clear)

Min score:

Reason:

Sort:

Unearthed Plague by mentil · 2016-09-10 19:57 · Score: 4, Informative

The summary suggests that some "what terror have you unleashed?!" doomsday scenario could unfold with Yersinia Pestis being resurrected from extinction... but that's impossible. Yersinia Pestis still exists and causes about a dozen cases of bubonic plague annually, nowadays. It's easily treated with antibiotics, and those of European descent are thought to be resistant to it. If I recall my Wikipedia correctly.

--
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
1. Re:Unearthed Plague by Z00L00K · 2016-09-10 20:08 · Score: 1
  
  In addition to the antibiotics the bacteria culled the part of the population that weren't resistant enough to cope with it. This is why the earliest occurrences of the Black Death usually were worst while the subsequent were milder. Darwin at work.
  
  --
  If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
2. Re:Unearthed Plague by 93+Escort+Wagon · 2016-09-10 20:08 · Score: 1
  
  It pops up in the "Four Corners" region of America"s southwest, every so often. It seems to hit the Navajo Nation semi-regularly.
  
  --
  #DeleteChrome
3. Re:Unearthed Plague by Hognoxious · 2016-09-10 21:14 · Score: 2, Funny
  
  those of European descent are thought to be resistant to it.
  I thought it was about London?
  
  --
  Confucius say, "Find worm in apple - bad. Find half a worm - worse."
4. Re:Unearthed Plague by ilguido · 2016-09-10 21:32 · Score: 3, Informative
  
  Easily treated is bit of an understatement. A properly treated bubonic plague causes a risk of death of 10% according to wikipedia, and there is still the problem that symptoms appear in a few days after contagion, and death in 7-10 days from contagion, so it is critical an early diagnosis. Septicemic and pneumonic plague are even worse.
5. Re:Unearthed Plague by Anonymous Coward · 2016-09-10 22:42 · Score: 1
  
  I love that - every piece of reassuring medical commentary should end with "If I recall my Wikipedia correctly".
6. Re:Unearthed Plague by Anonymous Coward · 2016-09-10 22:46 · Score: 5, Funny
  
  those of European descent are thought to be resistant to it.
  I thought it was about London?
  They're still European for another two years (and it's a rolling two years as it keeps not starting) only after that will they not be Europeans and any children they have at that point may not be immune to the plague unless they cover it in their negotiations - that's why it takes so long, there are a lot of issues like this to consider.
7. Re:Unearthed Plague by tomhath · 2016-09-10 23:44 · Score: 2
  
  The prairie dogs that live around there are a well known vector.
8. Re:Unearthed Plague by Anonymous Coward · 2016-09-11 02:11 · Score: 1
  
  I love that - every piece of reassuring medical commentary should end with "If I recall my Wikipedia correctly".
  Not just medical comments, every authoritative sounding statement should end this way - and that's not just a suggestion, it's actually the law in 37 states. If I remember my Wikipedia correctly.
9. Re:Unearthed Plague by K.+S.+Kyosuke · 2016-09-11 03:57 · Score: 1
  
  I thought the joke was about the comparative lack of native population in the area of London. Compared to, say, rural Scotland as the extreme case of the opposite.
  
  --
  Ezekiel 23:20
10. Re: Unearthed Plague by AF_Cheddar_Head · 2016-09-11 04:14 · Score: 3, Interesting
  
  Prairie dogs didn't carry plague until ranchers started using it to kill prairie dogs. So kind of poetic justice that they give it right back.
11. Re:Unearthed Plague by Anonymous Coward · 2016-09-11 11:08 · Score: 1
  
  It's easily treated with antibiotics, and those of European descent are thought to be resistant to it. If I recall my Wikipedia correctly.
  It is treatable by antibiotics but can still be bad if you wait too long. And there is no evidence that those of European descent have any greater resistance to it.
  At one point there was a paper which speculated that the CCR5 delta 32 mutation, a very rare mutation that exists and confers resistance/immunity to HIV, might have arisen as a selective response to the Black Death. But that was mere speculation, and it's not even been conclusively shown that having CCR5 delta 32 even helps you in the event you get plague. Nevertheless that is where this "Europeans are plague resistant" meme probably began.
12. Re:Unearthed Plague by saforrest · 2016-09-11 11:10 · Score: 1
  
  It's easily treated with antibiotics, and those of European descent are thought to be resistant to it. If I recall my Wikipedia correctly.
  It is treatable by antibiotics but can still be bad if you wait too long. And there is no evidence that those of European descent have any greater resistance to it.
  At one point there was a paper which speculated that the CCR5 delta 32 mutation, a very rare mutation that exists and confers resistance/immunity to HIV, might have arisen as a selective response to the Black Death. But that was mere speculation, and it's not even been conclusively shown that having CCR5 delta 32 even helps you in the event you get plague. Nevertheless that is where this "Europeans are plague resistant" meme probably began.
13. Re:Unearthed Plague by rustl · 2016-09-11 11:56 · Score: 1
  
  I thought that Yersinia Pestis has been known to be the organism responsible for the plague for a long time, this confirms it. From memory the theory was that the black plague was caused by a strain that was much more virulent than the one normally found now.
  The article states that they have found bacterial DNA in 5 samples and are still looking for more to reassemble the genome of the plague bacterium so they can compare it to the current genome.
14. Re:Unearthed Plague by saforrest · 2016-09-12 03:55 · Score: 1
  
  I thought that Yersinia Pestis has been known to be the organism responsible for the plague for a long time, this confirms it. From memory the theory was that the black plague was caused by a strain that was much more virulent than the one normally found now.
  The article states that they have found bacterial DNA in 5 samples and are still looking for more to reassemble the genome of the plague bacterium so they can compare it to the current genome.
  It's been shown that most of the plague variants alive today are descendants of the 1347 plague (the Black Death). The same goes for all the genomes we have from intermediate epidemics between 1348 and now, which will probably include the 1665 plague once the genomes are known. The big discovery is that there are almost no genetic differences between any of these strains. The strain that killed all those people in 1347 was basically the same strain you can find in prairie dogs in the American Southwest today. No one so far has provided a good explanation for why the 1347 outbreak was so much more deadly. Some of the offered explanations include coinfection (i.e. people were sick with something else and the plague finished them off), different living conditions, or maybe different vectors. Plague depends on a rodent and flea population and both the rodents and fleas in 1347 might have been different from today's.
15. Re:Unearthed Plague by RockDoctor · 2016-09-12 08:20 · Score: 1
  
  Hmmm, spent much time in rural Scotland in the last couple of decades? Very cosmopolitan region. Maybe not so cosmopolitan as a large city, but more cosmopolitan than a housing estate in a medium-sized town.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
dumb statement by bloodhawk · 2016-09-10 19:58 · Score: 3, Interesting

The thing to reassure people of is the fact the bubonic plague is treatable now unlike back then not that it can't live in the ground as that is a fairly pointless reassurance as the bacteria is still very much alive and well in the world. It still occasionally raises its head with outbreaks and results in 100+ deaths a year.
1. Re:dumb statement by Z00L00K · 2016-09-10 20:11 · Score: 1
  
  I would still worry more about tuberculosis and anthrax than the bubonic plauge.
  
  --
  If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
2. Re:dumb statement by Gussington · 2016-09-10 20:42 · Score: 2
  
  I'm more worried about heart failure or road trauma, but Plague and Muslims Jihadis sell more clicks...
3. Re:dumb statement by dunkelfalke · 2016-09-11 00:53 · Score: 1
  
  Not really dumb. That particular strain would be several centuries old - it potentially could be more unpleasant than the modern one.
  
  --
  "It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
4. Re: dumb statement by Anonymous Coward · 2016-09-11 18:13 · Score: 1
  
  We spend billions fighting disease and doing stupid and pointless things under the pretense that it will do anything about terror.
  
  FTFY.
At what point? by dohzer · 2016-09-10 21:45 · Score: 1

At what point are we allowed to dig up graves?
After 100 years? 200 years?
There are some massive cemeteries near me on land that could be repurposed rather than wasted.
1. Re:At what point? by Hognoxious · 2016-09-10 22:02 · Score: 4, Funny
  
  Whatever you do, never just move the headstones.
  
  --
  Confucius say, "Find worm in apple - bad. Find half a worm - worse."
2. Re:At what point? by Pax681 · 2016-09-10 22:12 · Score: 1, Interesting
  
  At what point are we allowed to dig up graves? After 100 years? 200 years? There are some massive cemeteries near me on land that could be repurposed rather than wasted.
  re-purpose them? that's some serious bollocks.. Here in Edinburgh, Scotland we STILL have "plague pits" as does EVERY town and city in Scotland.
  looking at Edinburgh you will see strange wee strips of land around the town and suburbs which are free ffrom housing and usually turned into gardens and fenced off.
  dog down far enough and you'll hit bone, lots of bone from dead people who died of the plague.
  These are NOT and never ill be dug up because....THE PLAGUE CAN LIE DORMANT FOR HUNDREDS OF YEARS and when you disturb that mass grave you are in for mass trouble.
  They also used plague pits for Typhus and anthrax outbreak victims.. basically any mass lergy and you ended up in a plague pit when you died. so these areas are NEVER and will NEVER be built upon.
  BTW it takes a special kind of cocksucker to want to dug up a grave, move bodies and build upon a grave site.
3. Re:At what point? by servies · 2016-09-10 22:40 · Score: 2
  
  Did you even read the article or the headline at all???
  
  "To reassure anyone worried whether plague bacterium was released from the excavation work or scientific analysis, it doesn't survive in the ground," reports the BBC.
4. Re:At what point? by Pax681 · 2016-09-10 22:55 · Score: 1, Interesting
  
  tell that to the City environment guys who shut us down quicker than Milo Yiannopolis shuts down a 3rd wave feminist!
  As I also mentioned... those same plague pits were also commonly used to typhus outbreak,smallpox, anthrax and any other mass lergy that happened.. everyone went into mass graves.
  Please feel free to phone the City of Edinburgh council Environment Dept to argue it out if you like.. +44 (0)131-200-2000 and ask them if it's ok to dig any areas of any of the plague pits in the city.... :-)
5. Re:At what point? by lxs · 2016-09-10 22:56 · Score: 5, Interesting
  
  What's this obsession with old bones?
  The people are gone. Those who mourned them are gone. Burn the remains and let vegetation reclaim the minerals.
6. Re:At what point? by Anonymous Coward · 2016-09-11 00:50 · Score: 2, Insightful
  
  I think the "rule of thumb" in the UK at least is that you own your plot for 70 years after which it's fair game, although the habbit of being buryed with or next to your spouse and / or children presumably resets the clock.
  The historic practice was that when the graveyard got full the oldest plots would be dug up and the bones would be placed in the ossuary (typically a small stone "tomb" you still see in some old graveyards) When the ossuary was full the bones would be removed and burnt on a "Bone Pyre" which is the origin of the word Bonfire. A lot of small village churches have tiny graveyards, with room for only a 2 dozen plots if that, still I'd imagine the Bury-Exhume-Inter-Burn cycle probably took over a century and it's unlikely that anybody particularly cared about who was getting cremated at that point.
7. Re:At what point? by HBI · 2016-09-11 02:18 · Score: 1
  
  These are useful concepts for the discussion.
  Technically, someone who has moved into the zamani has no need for a grave. No one alive remembers that person, and therefore there is no need to grieve, which is the only logical reason for having a grave site in the first place. Based on restrictions of human lifespan, the longest this could be would be a little over a hundred years. You can see this effect in re-used burial plots in urban areas, where they bury new coffins atop old and replace the headstones.
  This brings up a logistical issue with burial plots being re-used. If that is happening, and there are still people in the sasha in that burial place, then no one is going to be okay with bulldozing it and building a Walgreens.
  I'm not going to moralize with you about this - I don't believe it's a moral issue since I don't think our rotted corpses are anything more than fertilizer. But, I do suggest that the world would be a poorer place historically if we didn't have old graveyards. I'd like to keep them around.
  
  --
  HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
8. Re:At what point? by ledow · 2016-09-11 03:13 · Score: 2
  
  You're a moron:
  https://www.gov.uk/government/...
  "There are no records since 1981 of any person being infected as a result of disturbing soil for building or any other purpose." (35 years, and that's probably only because there were no records kept before that)
  "There is no evidence of any worker or member of the public being infected with anthrax as the results of development of brownfield sites including abattoirs and tanneries, areas traditionally associated with anthrax, or greenfield sites previously used for livestock."
  The others are all pretty much the same, you only have to do a bit of Googling.
  Or you could use your brain and say "I have no fucking idea where the soil in my garden has come from, what it might have had, who it might have been buried with over millions of years of diseases and plagues, and yet I don't die whenever I turn it over".
  Sure, eating that shit probably isn't a great idea because there are all kinds of fungi, spores and bacteria in it. But no less in plague pits from hundreds of years ago than in a bag you get from B&Q today. Fuck, most of the peat we use is tens of thousands of years old.
  If that's the real reason, rather than preserving those sites (if they are scheduled sites for archaeology, for example), then Edinburgh need to hire some fucking scientists. If only they had a university...
  If you can catch it from the soil, it's still active and killing people in the local area every day. That's not what's happening. Disturbing soil a couple of hundreds years old is like the crap that the pyramid had curses and diseases in them. Absolute bollocks. After that period of time, anything that can infect a host would have been without hosts for hundreds of years, and would have died at the first winter.
9. Re:At what point? by newcastlejon · 2016-09-11 03:47 · Score: 1
  
  BTW it takes a special kind of cocksucker to want to dug up a grave, move bodies and build upon a grave site.
  Why? It's not like bones care where they're buried, or what's above ground either.
  
  --
  If God forks the Universe every time you roll a die, he'd better have a damned good memory.
10. Re: At what point? by Anonymous Coward · 2016-09-11 04:03 · Score: 1
  
  Why not? That's how Link(Zelda) found one of the items he needed on his quest. He had to move many gravestones, if I remember Wikipedia correctly.
11. Re:At what point? by TechyImmigrant · 2016-09-11 06:34 · Score: 1
  
  No one alive remembers that person, and therefore there is no need to grieve, which is the only logical reason for having a grave site in the first place.
  Well there's also the preservation of pathogen DNA fragments for future scientists to dig up.
  
  --
  I should use this sig to advertise my book ISBN-13 : 978-1501515132.
12. Re:At what point? by ChrisMaple · 2016-09-11 06:46 · Score: 1
  
  Not to deny your main point, but the chance of infection increases with the quantity of the infecting agent. Most people are unlikely to get sick inhaling a couple of anthrax spores, but eat a pint of them and you're toast.
  Anthrax can survive hundreds of years of dormancy. There's a documented example of 370 years here: http://www.standard.co.uk/news/crossrail-work-stopped-after-human-bones-found-on-site-6759649.html
  
  --
  Contribute to civilization: ari.aynrand.org/donate
13. Re:At what point? by the+phantom · 2016-09-11 12:12 · Score: 2
  
  You might be willing to compromise on this for the sake of practicality, but I am not.
  What is there to compromise if I don't share you veneration of dead bone?
  
  --
  Rhapsody in Numbers
14. Re:At what point? by antdude · 2016-09-11 15:17 · Score: 1
  
  Ditto. If I ever die, just recycle my body. Geez. No point of putting my dead body in the coffin to bury. Let nature do its work!
  
  --
  Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
15. Re:At what point? by bobstreo · 2016-09-11 18:31 · Score: 1
  
  Whatever you do, never just move the headstones.
  Yeah that went well in Poltergeist.
16. Re:At what point? by RockDoctor · 2016-09-12 08:32 · Score: 1
  
  You're a moron:
  https://www.gov.uk/government/... [www.gov.uk]
  Wrong country, moron.
  Also wrong argument. If you expect research or data to move a petty bureaucrat jobsworth, then you have no experience of the Real World.
  I've never had to deal with Auld Reekie's Council, but dealt with others in the past. The planning and building approvals departments are "an experience". And not a nice one. Plus, of course, if you don't follow their dictates, they'll let you build what you want, then send their boys round (with the police to enforce it) to demolish your building and restore the site, then send you the bill. And bankrupt you if you don't pay it with a smile.
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
17. Re:At what point? by RockDoctor · 2016-09-12 08:44 · Score: 1
  
  I think the "rule of thumb" in the UK at least is that
  There is no "rule of thumb" for the UK.
  I'm not sure what the rules are in England and Wales. In Scotland, I believe that it's a matter of contract with whoever you lease the lair from. As long as your descendants continue to pay the ground rent on the lair, then it's safe from disturbance (barring errors). Stop paying, and if the ground has had enough time to decompose a body - which varies with latitude, altitude (temperature) and soil properties - then they'll happily re-lease the ground after a few decades. If they find bones, they'll stop digging (if the hole is deep enough (3 or so ft) and all that the lair. Or, if the lair is too shallow, they'll dig through to make a deep lair, then put the bones back in, cover with soil and then continue the burial.
  I had a friend who was a grave digger for a couple of years. That's Perthshire rules - I wouldn't bet on the rules being the same in neighbouring counties. Why would one expect them to be the same?
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Re:You should worry about smallpox by HBI · 2016-09-11 02:05 · Score: 1

I don't worry, i'm vaccinated. First one in 1970, just got a booster in 2007. What, you're not?

--
HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
Positive results were found in 5 of 20 individuals by DBCubix · 2016-09-11 02:30 · Score: 1

What about the other 75%? Is it a problem with the testing instrument or was there something else?

--
I called it a mighty Sperm Whale, she called it Finding Nemo.
Roughly? by synth7 · 2016-09-11 03:04 · Score: 1

"The 3,500 graves represent roughly 3.5% of London's 100,000 victims of the Great Plague"
If there were 100,000 victims, then 3,500 graves is *exactly* 3.5% of the total.
Perhaps the author meant to say "The 3,500 graves represent 3.5% of London's estimated 100,000 victims of the Great Plague."
1. Re:Roughly? by jittles · 2016-09-11 12:38 · Score: 1
  
  "The 3,500 graves represent roughly 3.5% of London's 100,000 victims of the Great Plague"
  If there were 100,000 victims, then 3,500 graves is *exactly* 3.5% of the total.
  Maybe because there were "roughly" 100,000 victims?
  I mean, who was counting back then.
  Me. Without cat videos on the internet, I had nothing better to do all day.
Re:Clearly a hoax by ledow · 2016-09-11 03:05 · Score: 2

Yeah, free dental care up to the age of 18, plus free dental care to those who can't afford it after that, and free dental care to those over 65.
What fucking bastards. Looking after people's teeth. For free! I mean, what fucks?! They should be paying a third-party for-profit company at least a thousand dollars a year for that, right?!
Fucking nanny states, making sure we're looked after, get to a dentists, have dentistry work and orthodontics that would cost tens of thousands in other countries, and that we get it for free. Almost like a... well, a nanny. Who cares for our kids.
Fucking moron.
Re:In 1348 the Black Death took 60% by K.+S.+Kyosuke · 2016-09-11 03:56 · Score: 1

Interestingly, I believe we still haven't conclusively determined yet that the Black Death was also caused by Yersinia pestis. Some interesting alternative explanations exist. Or at least they did a few years ago.

--
Ezekiel 23:20
Re:Clearly a hoax by newcastlejon · 2016-09-11 03:59 · Score: 1

Yeah, free dental care up to the age of 18, plus free dental care to those who can't afford it after that, and free dental care to those over 65.
Emphasis mine. Even if you can afford it dentistry is heavily subsidised. I went to have a wisdom tooth removed but found out there was an abscess there. It took three trips in all with some x-rays thrown in for good measure but I still only ended up paying £50-something for the extraction and £7-something for the antibiotics. I can't even imagine how much that would have cost in the US, even with insurance.

--
If God forks the Universe every time you roll a die, he'd better have a damned good memory.
Re:In 1348 the Black Death took 60% by Anonymous Coward · 2016-09-11 06:17 · Score: 2, Funny

What's an aleppo?
Re:In 1348 the Black Death took 60% by ChrisMaple · 2016-09-11 06:22 · Score: 4, Funny

Aleppo is the absence of leppo.

--
Contribute to civilization: ari.aynrand.org/donate
Re:Clearly a hoax by ChrisMaple · 2016-09-11 07:03 · Score: 1

Prices vary, but drilling out and capping an abscessed tooth is about $1200; I assume an extraction is less.
Here's an important difference: I pay for the dentist and his staff, and I'm paying for the damage that my inadequate care of my teeth caused. You're paying (on average) for the dentist and his staff and for a government bureaucrat. It's less efficient; the country as a whole is paying more than it would without the bureaucracy. Also, morality is being short-circuited: careless people pay little for the damage they cause; careful people are forced to pay for services they don't use.

--
Contribute to civilization: ari.aynrand.org/donate
Re:In 1348 the Black Death took 60% by saforrest · 2016-09-11 11:22 · Score: 4, Informative

Interestingly, I believe we still haven't conclusively determined yet that the Black Death was also caused by Yersinia pestis. Some interesting alternative explanations exist. Or at least they did a few years ago.
The fact that Y. pestis is responsible for the Black Death was conclusively determined a few years ago. In fact, the paleopathologist quoted in the featured article, Dr. Kirsten Bos, is the first author of a 2011 Nature paper presenting a genome of Yersinia pestis recovered from the remains of victims of the Black Death:
Kirsten I. Bos*, Verena J. Schuenemann*, G. Brian Golding, Hernán A. Burbano, Nicholas Waglechner, Brian K. Coombes, Joseph B. McPhee, Sharon N. DeWitte, Matthias Meyer, Sarah Schmedes, James Wood, David J. D. Earn, D. Ann Herring, Peter Bauer, Hendrik N. Poinar, Johannes Krause. “A draft genome of Yersinia pestis from victims of the Black Death”. Nature 478: 506–510. doi:10.1038/nature10549
Re:Positive results were found in 5 of 20 individu by RockDoctor · 2016-09-12 08:59 · Score: 1

Or maybe, only 1 in 4 of the sub-fossils had adequate preservation of detectable bacterial fragments.
Just for starters : they were looking at microbe fragments preserved in teeth - because these are some of the most decay-resistant bits of the entire body. But for 1665 I wouldn't be astonished if most people who went into the ground for any reason had either badly-eroded teeth (grit in bread) or badly-rotted teeth (caries), or just plain no teeth. If the enamel from a tooth had worn off in life to expose the dentine or tooth pulp, then any bacteria found in there could have come into the tooth at some time post burial. Likewise if there were a caries pit in the tooth, it's a potential entry point for post-mortem bacteria.
1 in 4 bodies yielding usable results doesn't sound at all bad to me. Incidentally, euipment failure wouldn't be an issue. You do the fieldwork one month. 6 months later, you get to "doing" the skeletons and decide which ones have teeth suitable for DNA work. Then you apply for a grant for the DNA work - if it's granted, you cut the teeth decided upon and extract your samples. Put them in liquid nitrogen while you're working on the other teeth in the sample. Then send them off to who-ever is doing your testing. If their equipment is having a bad hair day, then it might take 3 months to get the results instead of 2 months, or they farm it out to another lab.
They're not walking around with a Tricorder and a guy in a red shirt, zapping a bone sticking out of the mud and saying "Yersinia pestis!"

--
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"