Prevalence rates of helminths through time.
Prevalence of Ascaris, Trichuris, Taenia and Diphyllobothrium latum for four different time periods (Roman [n = 94], Anglo-Saxon [n = 79], High/Late Medieval [n = 159], and Industrial era [n = 116]). The confidence intervals are calculated using the Wilson Score interval (95% confidence level). Example photomicrographs of parasite eggs from left to right: Ascaris, Trichuris, Taenia and Diphyllobothrium latum Scale bar: 20 μm.
Devotees of creationism's intelligent [sic] malevolence will be thrilled by the news that scientists from Oxford University have discovered how successful it was at creating parasitic worms to make the life of Britons from earlier times just a little more miserable. (We can be sure that this was its intention because an omniscient creator could not create something with unintended consequence.)
What they may find harder to explain though, is why it didn't anticipate the improvements in our understanding of biology and the need for good hygiene, that led to a diminution of the problem later on and, with a few notable exceptions such as in London, an almost complete elimination of the problem.
By examining remains from 464 human burials, from 17 sites, dating from the Bronze Age to the Industrial Revolution, a team led by researchers from the Departments of Biology and Archaeology, Oxford, University, Oxford, UK, showed that the problem of parasitic worms was at it's highest in Britain during the late Roman and Late Medieval periods. With improved hygiene, however, the problem began to diminish, although, since progress in hygiene was patchy in the Victorian era, the pattern of parasite infection varied markedly. In London, for example, it was as bad as that seen in the wordst affected areas today, whilst in other areas, it was almost non-existant.
As the OU Department of Zoology News release explains:
Understanding how parasitic worm infections changed in the past can help public health measures in regions of the world still experiencing problems today.More details are given in the abstract and author summary to the open access paper, published in PLOS Neglected Tropical Diseases last week:
Humans are infected with roundworms and whipworms through contamination by faecal matter, and catch some tapeworms by eating raw or undercooked meat or fish.
Infections with parasitic worms are a big problem in many parts of the world today, particularly in some tropical and sub-tropical regions of the world. But in the past they were much more widespread and were common throughout Europe.Defining the patterns of infection with intestinal worms can help us to understand the health, diet and habits of past populations. More than that, defining the factors that led to changes in infection levels (without modern drugs) can provide support for approaches to control these infections in modern populations.
Hannah Ryan, joint first author
Wellcome Trust Palaeogenomics &
Bio-Archaeology Research Network
University of Oxford, Oxford, UK.
And Patrik Flammer, joint first author
Department of Zoology
University of Oxford, Oxford, UK.
The research team wanted to find out the size and scale of parasitic worm infections in the UK over the course of history. So they looked for worm eggs in the soil from the pelvises of skeletons.
They tested a lot of individual skeletons. 464 human burials were examined from 17 sites, dating from the Bronze Age to the Industrial Revolution.
People In the Roman and the Late Medieval period fared the worst, with the highest rates of worm infection detected. The infection rates were similar to those seen in the most affected regions today.
Things changed in the Industrial period. Worm infection rates differed a lot between different sites – some sites had little evidence of infection, while in others there was a lot of infection.
The researchers think that local changes in sanitation and hygiene may have reduced infection in some areas before nationwide changes during the Victorian “Sanitary Revolution”.
Copyright: © 2022 The authors. Published by PLOS.Open access. (CC BY 4.0)
AbstractFrom an evolutionary biologist's perspective on this data, clearly, a changing environment in the form of improved hygiene, impacted on these parasitic species and made some of them locally extinct, exactly as we would expect from the TOE. What is hard to explain though is how this fits in with a creationist perspective, where a magic designer created these parasites to do exactly what they do - increase human misery and suffering and make life a little more unpleasant for the parasites' hosts, and yet this supposedly omniscient designer failed to anticipate that humans would learn how to avoid them and even exterminate them, at least locally, by improving their standards of cleanliness because it had designed them to depend on dirty drinking water, uncooked meat and contamination with faeces in order to infect new victims.
Intestinal helminth parasites (worms) have afflicted humans throughout history and their eggs are readily detected in archaeological deposits including at locations where intestinal parasites are no longer considered endemic (e.g. the UK). Parasites provide valuable archaeological insights into historical health, sanitation, hygiene, dietary and culinary practices, as well as other factors. Differences in the prevalence of helminths over time may help us understand factors that affected the rate of infection of these parasites in past populations. While communal deposits often contain relatively high numbers of parasite eggs, these cannot be used to calculate prevalence rates, which are a key epidemiological measure of infection. The prevalence of intestinal helminths was investigated through time in England, based on analysis of 464 human burials from 17 sites, dating from the Prehistoric to Industrial periods. Eggs from two faecal-oral transmitted nematodes (Ascaris sp. and Trichuris sp.) and the food-derived cestodes (Taenia spp. and Diphyllobothrium latum syn Dibothriocephalus latus) were identified, although only Ascaris was detected at a high frequency. The changing prevalence of nematode infections can be attributed to changes in effective sanitation or other factors that affect these faecal-oral transmitted parasites and the presence of cestode infections reflect dietary and culinary preferences. These results indicate that the impact of helminth infections on past populations varied over time, and that some locations witnessed a dramatic reduction in parasite prevalence during the industrial era (18th-19th century), whereas other locations continued to experience high prevalence levels. The factors underlying these reductions and the variation in prevalence provide a key historical context for modern anthelmintic programs.
Author summary
Parasitic worms (helminths) cause many health problems in poorer countries, particularly those in tropical and sub-tropical regions. In modern Europe these infections are very rare and mostly found in those travelling from endemic areas but this wasn’t always the case. Archaeological studies have detected eggs of parasitic helminths in numerous European sites. Key questions include how prevalent these infections were in past communities and whether (or when) these patterns changed over time? This paper addresses both of these questions using a large number of single grave samples from archaeological sites in England dating between Prehistoric and Industrial periods. Helminth infections were detected across all periods but the overall prevalence rates changed over time, being highest in the Roman and Late-Medieval periods. The Industrial period was interesting in that two of the three sites contained very few (or no) parasites whereas the third, London, contained high levels of infection. We discuss factors that may have contributed to the changing parasite landscape and how understanding these factors may influence efforts to control helminth infections in modern endemic areas.
Ryan H, Flammer PG, Nicholson R, Loe L, Reeves B, Allison E, et al. (2022)
Reconstructing the history of helminth prevalence in the UK.
PLoS Negl Trop Dis 16(4): e0010312. https://doi.org/10.1371/journal.pntd.0010312
Open access
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)
In all probability, they will abandon any pretence that ID is science and resort to religious superstitions such as 'The Fall' and 'ineffable mysteries' to explain these findings and so, unlike science, will fail to provide anything that could be useful in other parts of the world where these parasites are still endemic.
No comments:
Post a Comment
Obscene, threatening or obnoxious messages, preaching, abuse and spam will be removed, as will anything by known Internet trolls and stalkers, by known sock-puppet accounts and anything not connected with the post,
A claim made without evidence can be dismissed without evidence. Remember: your opinion is not an established fact unless corroborated.