Death and Decomposition of the microbiome

extra credit presentation micro bio

1. Death and Decomposition Necrobiome Medical Microbiology

2. What and When is Death Definition of death: “…an individual who has sustained either (1) irreversible cessation of circulatory and respiratory functions, or (2) irreversible cessation of all functions of the entire brain, including the brain stem, is dead.” - U S President’s Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research set up by Ronald Reagan (1981) The end of life Signs of death: Respiratory arrest: no breathing Cardiac arrest: no pulse Brain death: no neuronal activity Forensic Pathology – a 5-stage Process of Decomposition

3. Forensic Pathology- a 5 Stage Process of Decomposition Stage One: Autolysis (0-3 days) Corneal opacity : “clouding” in the eyes Pallor mortis : paleness (15-120 minutes after death) Livor mortis: a setting of the blood due to gravity Algor mortis: reduction of body temperature Rigor mortis: stiffening of the limbs Stage Two: Bloat (2-6 days) Putrefaction : beginning of the decomposition Gases produced by bacteria digesting the body causing the body to swell Strong odor: cadaverine, putrescine, skatole, indole Stage Three: Active Decay (5-11 days) Decomposition accelerates due to bacteria, insects, and other organisms Stage Four: Advanced Decay (10-25 days) Body tissue begins to break down further, with less visible mass Stage Five: Skeletonization (1 month+) Remaining tissue breaks down, leaving only the skeleton

4. García MG, Pérez- Cárceles MD, Osuna E, Legaz I.2020.Impact of the Human Microbiome in Forensic Sciences: a Systematic Review. Appl Environ Microbiol86:e01451-20.https://doi.org/10.1128/AEM.01451-20 Figure A ) Representative diagram of the changes in microbiota during the different stages of human decomposition Figure Figure B) Representation of microbial communities present before and after the bloat stage in human decomposition Candy question… Are the microbes found on dry remains also present In you? Yes! Bacillus species are also found in human flora, such as the skin and gut. Clostridium is a normal part of the gut microbiota in us humans! Microbes most abundant at each stage of death

5. Life After Death-The Reason for Life

6. Environmental Factors: Temperature: Heat accelerates decay, cold slows it down Humidity: Wet conditions speed up decomposition, dry condition slows it down Clothing and Burial: Embalming : a process of preserving human remains Replace the body's blood with preservative fluids. Formaldehyde-based chemical solutions Body decomposition is slower if the body is buried or in a sealed container The presence of clothing or wrapping can also affect the rate of decomposition Factors Affecting Decomposition

7. Nursing and Death How do you know when a patient is close to death? How do you a support a patient who is close to death? What kind of care should be given to a patient directly before and after death? How do you stay emotionally stable after seeing and experiencing patient death?

8. When a patient is nearing death… How to know Changes in breathing patterns Changes in behavior Increased fatigue, weakness, or sleepiness Changes in skin Decreased activity levels “Deathbed gifts” Confusion/hallucinations Irregular, slow, shallow, or pauses Excessive noise while breathing Can be pale or mottled (discoloration) May be cold to the touch Especially true in the hands and feet How to support the patient Symptom management Staying compassionate and empathetic Providing support and resources for family members and loved ones Recognizing death is a unique experience for every individual Pain management Administering medications Symptom anticipation Environmental comfort Developing strong communication skills Unique cultural and/or spiritual beliefs and needs Different emotional stages Ex. denial, shock, fear, acceptance

9. Post-mortem Care Patient’s family Provide education and support Cultural sensitivity Allow space/time to grieve Preparing patient’s body Elevating the head, supine position Prevents livor mortis (discoloration) of the face Removing any medical equipment Cleaning the body Proper documentation Time of death, resuscitation efforts, etc.

10. Caring for Yourself Developing healthy coping mechanisms Meditation, exercise Support from colleagues and/or loved ones Religion and prayer Professional therapy Stay kind to yourself It is not an easy thing to deal with Everyone is different, Find what is best for you. Witnessing death is difficult.

11. Fun Interesting Facts Due to decomposition being something that is quite difficult to study, as most people die in nursing homes/hospitals Did you know you can donate your body to a “body farm” https://allthatsinteresting.com/body-farms These farms have helped further research in very little known of the necrobiome. Yellow color due to bacterial production to sulfur

12. Fun Interesting Facts https://fac.utk.edu/ https://www.txst.edu/anthropology/facts/aboutus.html Bad news about donating your body, your final resting place is either Tennessee or Texas But if you go to their website each have a link to donations….money….or body.

13. Fun Interesting Facts (last one) Due to reading the guidelines for body donation, we learned some fun new facts! Why does the document mention Covid-19? “We reserve the right to decline donations of individuals who have any form of infectious disease such as HIV, tuberculosis, hepatitis , or coronavirus of any kind (COVID-19, SARS, etc.); prion-related diseases (Creutzfeldt-Jakob Disease, Kuru, etc.); infections such as sepsis ; or any Multi-Drug Resistant Organisms (MDRO’s ) including antibiotic resistant infections such as MRSA even if contracted after donation is arranged . We also reserve the right to decline a donation if our facility is at capacity. In case of denial by the University, alternate final arrangements should be discussed between the donor and their family/legal representative. The FAC is not responsible for any costs associated with alternate arrangements.” Come to find out research was done on transmissibility after death, and conclusion was yes it can. Kiyoko   Iwatsuki -Horimoto ,  Hiroshi   Ueki ,  Mutsumi   Ito ,  Sayaka   Nagasawa ,  Yuichiro   Hirata ,  Kenichiro   Hashizume ,  Kazuho   Ushiwata ,  Hirotaro   Iwase ,  Yohsuke   Makino ,  Tetsuo   Ushiku ,  Shinji   Akitomi ,  Masaki   Imai ,  Hisako   Saitoh ,  Yoshihiro   Kawaoka bioRxiv  2022.08.29.505777;  doi : https://doi.org/10.1101/2022.08.29.505777 https://ncceh.ca/resources/evidence-briefs/covid-19-risks-handling-deceased

14. Resources 1. Humerus Revelations of the Naked Ape: Ashes to Ashes, Dust to Dust: The Stages of Decomposition 2.   William D. Haglund; Marcella H. Sorg , eds. (1997).  Forensic taphonomy : the postmortem fate of human remains . Boca Raton: CRC Press.  ISBN   0-8493-9434-1 .  OCLC   35236386 . 3. Microbiology of death: Current Biology 4. The Primary and Obvious Meaning of “Death” – An Excerpt – A : A 5. Keenan, S.W., Emmons, A.L. & DeBruyn, J.M. Microbial community coalescence and nitrogen cycling in simulated mortality decomposition hotspots . Ecol Process 12, 45 (2023). https://doi.org/10.1186/s13717-023-00451-y 6. Allison R Mason, Lois S Taylor, Jennifer M DeBruyn, Microbial ecology of vertebrate decomposition in terrestrial ecosystems, FEMS Microbiology Ecology, Volume 99, Issue 2, February 2023, fiad006, https://doi.org/10.1093/femsec/fiad006 7. García MG, Pérez- Cárceles MD, Osuna E, Legaz I.2020.Impact of the Human Microbiome in Forensic Sciences: a Systematic Review. Appl Environ Microbiol86:e01451-20. https://doi.org/10.1128/AEM.01451-20 8. Cobaugh KL, Schaeffer SM, DeBruyn JM. Functional and Structural Succession of Soil Microbial Communities below Decomposing Human Cadavers. PLoS One. 2015 Jun 12;10(6):e0130201. doi : 10.1371/journal.pone.0130201. PMID: 26067226; PMCID: PMC4466320. 9. Riedel S. The value of postmortem microbiology cultures. J Clin Microbiol . 2014 Apr;52(4):1028-33. doi : 10.1128/JCM.03102-13. Epub 2014 Jan 8. PMID: 24403308; PMCID: PMC3993482.