Thanatomicrobiome – State Of The Art And Future Directions

Abstract

Microbiological studies show that there is a possibility of PMI estimation in reference to presence of typical bacteria and fungi on cadaver or in soil beneath. Microbiome after death (thanatomicrobiome) changes and depends on time since death, temperature, seasons and environment-if human remains are covered, buried, placed in ice or left on the surface. To enlarge current knowledge, some of studies are conducted on animal models with further comparison thanatomicrobiome of different animals-pig, rats-to human cadaver thanatomicrobiome. This study collects different branches of thanatomicrobiome studies as a review to summarize current knowledge. 1. Introduction. 2. Living host microbiome and mycobiome. 3. Diseases-related differences. 4. Thanatomicrobiome – human cadavers studies. 5. Fungi presence – thanatomycobiome. 6. Thanatomicrobiome of frozen cadavers. 7. Soil microbial communities changes. 8. Seasons related microbial changes. 9. Thanatomicrobiome and entomology correlation. 10. Conclusions

Microbial communities in the liver and brain are informative for postmortem submersion interval estimation in the late phase of decomposition: A study in mouse cadavers recovered from freshwater

“…First, bacteria from the external environment and gut would influence the microbial community in viscera. Sterile organs could be colonized by infiltrating bacteria, and tissues where there is a specific microbiota can be contaminated ( Wójcik et al, 2021 ). The genus Aeromonas is ubiquitous in freshwater but absent in the healthy human body ( Goncalves Pessoa et al, 2019 ), and it has been documented as a potential bacterial marker of freshwater drowning ( Kakizaki et al, 2011 ; Huys et al, 2012 ; Uchiyama et al, 2012 ).…”

“…Bacteria are ubiquitous in natural bodies of water, and they are small (0.2–2.0 μm), which facilitates their entrance into blood circulation and their deposition in the viscera during drowning ( Oliveira and Amorim, 2018 ). A previous study indicates that various bacteria spread around the entire corpse after death ( Wójcik et al, 2021 ). Specific genera, including Aeromonas in freshwater and Vibrio and Photobacterium in seawater, are indicators of drowning when they are detected in the blood and viscera of victims via culture-dependent and/or PCR-based methods ( Kakizaki et al, 2008 ; Aoyagi et al, 2009 ).…”

Microbial traces and their role in forensic science

“…The tissue remnants get into the soil, enriching it with additional nutrients, which results in a shift of the species composition of the local microflora. A space called CDI (cadaver decomposition island) is formed around the corpse, within which the growth of species originally inhabiting the body of the deceased is observed (Adserias-Garriga et al, 2017;Wójcik et al, 2021). The phenomenon of the homogenization of soil and cadaver microbiome over time is yet another way to determine PMI, but in this case, based on research related to the development of the epinecrotic community (Damann et al, 2015;Metcalf et al, 2013Metcalf et al, , 2016.…”

“…pigs or mice) (Can et al, 2014; Heimesaat et al, 2012; Lawrence et al, 2019). The real challenge, however, is a correct interpretation of the results, requiring not only assessment by an experienced microbiologist, but also as much comparative data as possible, collected during research or criminal investigations, for example, medical history of the deceased, toxicological analysis, details about the location of the body or environmental conditions (Javan et al, 2019; Ventura Spagnolo et al, 2019; Wójcik et al, 2021).…”

“…Importantly, due to the site‐specific conditions, the microbial composition varies among body parts. Thus, different species are found in the composition of, for example, skin, oral or gut microbiome (Wójcik et al, 2021). The knowledge of factors influencing the human resident flora is useful in the studies of the thanatomicrobiome (Dekaboruah et al, 2020; Gilbert et al, 2018; Grice & Segre, 2012; Pechal et al, 2018; Rackaityte & Lynch, 2020).…”