Razmaz bubonske kuge pod mikroskopom, ki prikazuje prisotnost bakterij Yersinia pestis. | Foto: PROFIMEDIA
Novo odkritje v Sibiriji bi lahko korenito spremenilo razumevanje ene najbolj smrtonosnih bolezni v zgodovini. Analiza starodavne DNK je razkrila doslej neznan sev kuge, ki je pred približno 5.500 leti prizadel skupnosti lovcev in nabiralcev, kar pomeni, da se je bolezen med ljudmi širila veliko prej, kot so domnevali znanstveniki.
Oglaševanje
Kuga je ena najbolj uničujočih bolezni v človeški zgodovini, vendar pa zgodnji sevi bakterije Yersinia pestis , povzročiteljice kuge, vse do obdobja pred približno 3.800 leti niso imeli značilnosti, ki bi omogočili njihovo širjenje in razvoj v nalezljivo obliko bolezni.
Vsaj tako so znanstveniki mislili doslej. Starodavna DNK, ki so jo raziskovalci pridobili iz pokopališč v jugovzhodni Sibiriji, pa je razkrila doslej neznane seve kuge, ki so pred 5.500 leti smrtonosno prizadeli skupino ljudi.
Zgodnji sevi kuge, opisani v novi študiji, ki je bila v sredo objavljena v reviji Nature , bi tako lahko predstavljali najstarejši doslej znani dokaz o tej bolezni pri ljudeh.
Nov sev prinesel nepričakovan obrat
Kugo povzroča bakterija Yersinia pestis , ki je bila odgovorna za nekatere najbolj uničujoče izbruhe bolezni v človeški zgodovini, med drugim tudi za zloglasno pandemijo črne smrti v 14. stoletju, ki je v petih letih po nekaterih ocenah zahtevala 25 milijonov življenj.
Pred odkritjem na novo identificiranega seva so bili nekateri najzgodnejši znani sevi bakterije Yersinia pestis , povezani z bubonsko kugo, datirani v obdobje pred približno 3.800 leti. Starejši sevi naj bi bili brez genetskih značilnosti, ki so omogočile njihovo širjenje, zato so znanstveniki menili, da zgodnje oblike kuge verjetno niso povzročale večjih izbruhov.
Ker je bilo dokazov o drugih smrtonosnih predhodnikih bolezni malo, so se raziskovalci spraševali, kdaj in kje je bakterija sploh nastala, preden se je prek živine, kot so ovce, in okuženih bolh razširila na ljudi.
Novo odkriti sev pa je v zgodbo vnesel nepričakovan preobrat. Raziskovalci so nanj naleteli med reševanjem druge uganke, povezane z ostanki lovcev in nabiralcev, pokopanih na pokopališčih v območju Bajkalskega jezera. Na dveh največjih pokopališčih so našli nenavadno veliko število otrok in mlajših mladostnikov, pri katerih na posmrtnih ostankih ni bilo zaznati nobenih poškodb ali očitnega vzroka smrti.
Prizor z Bajkalskega jezera, Sibirija. | Foto: PROFIMEDIA
Raziskovalcem je uspelo iz zob izluščiti starodavne bakterijske genome, analiza starodavne DNK v posmrtnih ostankih pa je razkrila nepričakovano prisotnost bakterije kuge pri 18 od 46 posameznikov iz teh majhnih, mobilnih skupnosti.
Po mnenju strokovnjakov ugotovitve ponujajo nove dokaze o možnem izvoru kuge ter hkrati postavljajo pod vprašaj dosedanje predstave o tem, kaj je omogočilo njeno širjenje.
"Lovci in nabiralci so se nenehno premikali po pokrajini," je po pisanju CNN na torkovi novinarski konferenci ob predstavitvi rezultatov povedal vodilni avtor študije Ruairidh Macleod , raziskovalec na Univerzi v Oxfordu. "Prevladujoča teorija pravi, da nalezljive bolezni v takšnih okoliščinah težko opustošijo celotne skupnosti. Običajno naj bi se bolni posamezniki preprosto preselili drugam. Dejstvo, da opažamo takšen pojav v izolirani skupini prazgodovinskih lovcev in nabiralcev, pa postavlja pod vprašaj to epidemiološko teorijo," je dodal.
Nepričakovan izbruh
Arheologi že desetletja izkopavajo štiri starodavna pokopališča v okolici Bajkalskega jezera. Območje je bilo bogato z naravnimi viri, vključno z vodami, bogatimi z ribami, pokopališča pa kažejo, da so lovci in nabiralci svoje mrtve pokopavali v bližini skozi več generacij, morda tudi zato, da bi s tem simbolično utrjevali svojo pravico do tega ozemlja, je pojasnil Macleod.
Avtorji študije so združili napredno sekvenciranje DNK, podrobne arheološke raziskave in radiokarbonsko datiranje, da bi ustvarili celovito sliko dogajanja v tej regiji pred tisočletji. "Radiokarbonski dokazi so zelo jasno pokazali, da se je ta dogodek množične smrtnosti zgodil v zelo, zelo kratkem časovnem obdobju," je dejal Macleod in dodal: "Vse te smrti so se torej zgodile sočasno."
Genetske raziskave pa so osvetlile sorodstvene vezi med pokopanimi na teh pokopališčih. V nekaterih primerih so bili skupaj pokopani bratje in sestre ter starši z otroki, kar nakazuje, da se je bolezen prenašala med družinskimi člani, ko so skrbeli drug za drugega. To hkrati kaže tudi na pomanjkljivo razumevanje načinov širjenja bolezni, je pojasnil soavtor študije Eske Willerslev , evolucijski genetik in profesor na Univerzi v Københavnu ter Univerzi v Cambridgeu.
V drugih grobovih so našli sorodnike, pokopane ločeno, kar po ugotovitvah študije verjetno pomeni, da so umrli v različnih valovih bolezni. Raziskovalci menijo, da sta se v tej regiji pojavila dva izbruha kuge, med katerima je minilo nekaj sto let.
DNK bakterije kuge so raziskovalci odkr…
Read the full article at N1 Slovenija →📄Source document: Nature→6 reports
N1 SlovenijaIndependentCenter2 days agoA new discovery in Siberia suggests that plague, caused by the bacterium Yersinia pestis, may have affected human populations much earlier than previously believed. Analysis of ancient DNA from burial sites in southern Siberia has revealed previously unknown strains of the disease dating back approximately 5,500 years. This challenges previous assumptions that the plague became infectious and spread among humans only around 3,800 years ago.
Bias read (Center): The article presents scientific findings without overt ideological framing. It focuses on the implications of the discovery for historical understanding of the plague, citing peer-reviewed research published in 'Nature'. The tone remains neutral, emphasizing the significance of the findings without
TVN24IndependentCenter3 days agoA recent study has revealed that the earliest known plague epidemic occurred over five thousand years ago in Siberia, affecting hunter-gatherer communities around Lake Baikal. Researchers analyzed DNA from four burial sites and identified the oldest known strains of Yersinia pestis, the bacterium responsible for plague. The findings suggest that the disease originated in Central Asia or Northeastern Asia, with marmots serving as the initial hosts. The study also highlights that two-thirds of those who died were under 15 years old, indicating a high mortality rate among children and teenagers.
Bias read (Center): The article discusses scientific research on an ancient plague outbreak, focusing on historical data and biological findings. There is no political framing, ideological emphasis, or biased language present. The content remains purely factual and neutral.
Official sources cited
- study International team of scientists
Proto ThemaIndependentCenter3 days agoResearchers have discovered ancient DNA from human remains found at four locations around Lake Baikal in Siberia, revealing the presence of the oldest known strains of the plague bacterium Yersinia pestis. These findings suggest that hunter-gatherer communities living in the region approximately 5,500 years ago were victims of an early epidemic of bubonic plague, which was particularly deadly for children and adolescents. The genetic characteristics of this ancient strain differ from modern forms of the pathogen.
Bias read (Center): The article presents scientific research findings without apparent ideological framing. It focuses on archaeological and biological discoveries with no political implications or biased language.
Official sources cited
- study Ancient DNA Analysis Reveals Early Plague Strain in Siberia
Folha de S.PauloIndependentCenter3 days agoA research study published in the journal Nature reveals that the earliest known plague outbreak occurred 5,500 years ago in Siberian hunter-gatherer communities, significantly impacting children. This finding challenges previous assumptions about the spread of plague, suggesting it did not rely on fleas or high population densities associated with agricultural villages. The study was led by researchers from the University of Copenhagen, the University of Oxford, and other institutions.
Bias read (Center): The article presents scientific findings without overt ideological framing. It focuses on historical disease patterns and does not take a stance on contemporary political issues. The language remains neutral, emphasizing the academic nature of the discovery and its implications for understanding the
El MundoIndependent🔒Center3 days agoA new study published in the journal Nature reveals evidence of deadly plague outbreaks among hunter-gatherer communities 5,500 years ago. Researchers sequenced DNA from human remains found in four cemeteries near Lake Baikal in Eastern Siberia. By analyzing genetic data alongside archaeological findings and radiocarbon dating, they reconstructed how different plagues affected the region's populations. The lead author, Eske Willerslev, suggests that the plague originated in Central Asian hunter-gatherer communities and that mass mortality outbreaks were likely common, challenging the notion of
Bias read (Center): The article presents scientific research without overt ideological framing. It focuses on historical disease patterns and does not take a stance on contemporary political issues.
El PaísIndependent🔒Center4 days agoResearchers have discovered the oldest known outbreak of plague in the region around Lake Baikal in Siberia, dating back approximately 5,500 years. The study, published in the journal Nature, indicates that the bacterium responsible for the plague lacked some of the genes that later contributed to its high virulence but was still lethal, particularly to children. The findings were based on archaeological evidence from the Ust’-Ida site, which showed an unusual pattern of mortality with a significant number of child and adolescent deaths.
Bias read (Center): The article presents scientific research without overt ideological framing. It focuses on historical and biological findings, using neutral language and citing academic sources. There is no clear emphasis on political implications or partisan perspectives.
