pathogens

dna-analysis-reveals-likely-pathogens-that-killed-napoleon’s-army

DNA analysis reveals likely pathogens that killed Napoleon’s army

Biology, DNA analysis, forensic archaeology, history, Napoleon Bonaparte, pathogens, Science / /

State-of-the-art methodologies

Painting of Napoleon's army.

Rascovan and his co-authors note in their paper that the 2006 study relied upon outdated PCR-based technologies for its DNA analysis. As for the virus family detected in the Kalingrad dental pulp, they argue that those viruses are both ubiquitous and usually asymptomatic in humans—and thus are unlikely to be the primary culprits for the diseases that wiped out the French army. So Rascovan’s team decided to use current state-of-the-art DNA methodologies to re-analyze a different set of remains of Napoleonic soldiers who died in Vilnius.

“In most ancient human remains, pathogen DNA is extremely fragmented and only present in very low quantities, which makes it very difficult to obtain whole genomes,” said Rascovan. “So we need methods capable of unambiguously identifying infectious agents from these weak signals, and sometimes even pinpointing lineages, to explore the pathogenic diversity of the past.”

An 1812 report from one of Napoleon’s physicians, J.R.L. de Kirckhoff, specifically noted typhus, dysentery, and diarrhea after the soldiers arrived in Vilnius, which he attributed to large barrels of salted beets the starving troops consumed, “greatly upsetting us and strongly irritating the intestinal tract.” Rascovan et al. note that such symptoms could accompany any number of conditions or diseases common to 19th-century Europe. “Even today, two centuries later, it would still be impossible to perform a differential diagnosis between typhus, typhoid, or paratyphoid fever based solely on the symptoms or the testimonies of survivors,” the authors wrote.

Imperial Guard button discovered during excavation

Imperial Guard button discovered during excavation. Credit: UMR 6578 Aix-Marseille Université, CNRS, EFS

Over 3,200 individual remains, almost all men between the ages of 20 and 50, were excavated from the mass grave at Vilnius. Rascovan et al. focused on 13 teeth from 13 different individuals. To compensate for the degraded nature of the 200-year-old genome fragments, co-authors at the University of Tartu in Estonia helped develop a multistep authentication method to more accurately identify pathogens in the samples. In some cases, they were even able to identify a specific lineage.

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Tattoo ink sold on Amazon has high levels of weird and rare bacteria

bacteria, contamination, fda, health, microbiology, pathogens, recall, Science, Tattoo, tattoo ink / /

Infectious ink —

The recall announcement noted that the germs “present a health concern.”

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BARCELONA, SPAIN - 2021/10/02: Spanish tattoo artist Oscar Garcia works on a man, during the Expo. Fira de Barcelona hosts the XXIV edition of the Barcelona Tattoo Expo where tattoo artists from Spain and other countries exhibit tattoos and tattoo material such as ink, needles and special machinery for tattoo work. (Photo by Ramon Costa/SOPA Images/LightRocket via Getty Images)

Enlarge / BARCELONA, SPAIN – 2021/10/02: Spanish tattoo artist Oscar Garcia works on a man, during the Expo. Fira de Barcelona hosts the XXIV edition of the Barcelona Tattoo Expo where tattoo artists from Spain and other countries exhibit tattoos and tattoo material such as ink, needles and special machinery for tattoo work. (Photo by Ramon Costa/SOPA Images/LightRocket via Getty Images)

The Food and Drug Administration has been warning for years that some tattoo inks are brimming with bacteria—a large assortment that, when injected into your skin, can cause inflammatory reactions, allergic hypersensitivity, toxic responses, and, of course, straight-up infections. And, worse yet, the labels that say the inks are sterile are not reliable.

But, a recent recall of three tattoo pigments from the same manufacturer does a good job of illustrating the FDA’s concerns. The water-based inks, all from Sierra Stain, had a bizarre array of bacteria, which were found at high levels, according to FDA testing.

One ink product—described as “Carolina Blue”—offered a microbial menagerie, with six odd species identified. They included a bacterium that often dwells in the gastrointestinal system and can inflame the mucosal lining of the intestines (Citrobacter braakii), a water-borne bacterium (Cupriavidus pauculus), and several that cause opportunistic infections (Citrobacter farmer, Achromobacter xylosoxidans, Ochrobactrum anthropi, and Pseudomonas fluorescens). These are bacteria that don’t typically go about attacking humans but will if the conditions are right, including when they find themselves inside a human with a compromised immune system.

An ink called “UV China Pink” contained an unusual soil bacterium (Curtobacterium citreum/pusillum). And an “All Purpose Black” ink puzzlingly contained Acetobacter senegalensis, a bacterium first isolated from mangos in Senegal and used for industrial vinegar production in low-income countries.

The three inks were sold nationwide through Amazon. To date, there have been no reported infections or adverse reactions linked to these inks. But the FDA notes that reactions to contaminated inks can be difficult to accurately diagnose. The infections and skin responses can look like generic rashes and allergic responses, sometimes including lesions with red papules in areas where the ink was injected, the FDA notes. However, infections from tattoo ink can leave permanent scarring.

In a study published in July in Applied and Environmental Microbiology, FDA researchers tested 75 samples of tattoo and permanent makeup inks from 14 manufacturers. Of the 75 inks, 26 (35 percent) were contaminated with a total of 34 types of bacteria, many that were possibly disease-causing. Some of the bacteria were anaerobic, meaning they don’t need oxygen to grow, suggesting they could thrive in the low-oxygen environment of skin layers. Of the 40 tattoo inks specifically, nine (22 percent) were contaminated. Among all the ink samples, 49 were labeled “sterile” and, of those, 16 (33 percent) were contaminated.

The recall announcement noted that Sierra Stain is no longer in business. While the company lists a remaining email address, it did not immediately respond to a comment request from Ars on the bacteria found in their inks.

The FDA recommends that consumers be vigilant about the quality and safety of tattoo supplies and techniques. It also encourages tattoo artists to work in professional environments that can reduce the risk of contamination.

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