Salmonella enterica: foodborne illness

This is a curated page. Report corrections to Microbewiki.

When a person dies, their body ceases to work. Their heart fails to pump blood. Their lungs fail to take in oxygen. However, the microbes that dwell within the body do not die with the body. Because of this, forensic experts can use bodily microbes to help identify the time of death of a corpse. When the body dies, it goes through several phases of decomposition. The first step is Algor mortis, which is the cooling of body temperature. This occurs during the first 24 hours after death. After approximately 3 hours, rigor mortis will set in, causing the body’s muscles to contract and the corpse to appear stiff. This typically lasts between 36-48 hours. Lastly, the skin will appear reddish-purple in color due to Livor mortis. This usually occurs within the first hour after death and reaches a fixed state within 12 hours. This occurs due to the lack of arterial pressure, causing the blood to pool to the bottom of the corpse. Three days after rigor mortis sets in, the body begins to soften and the next stage of decomposition begins. This is where the bodily microbes come into play. Although bacterial rates are an accurate way to measure postmortem stages, there are still limitations to these methods. For example, if a body is found in an advanced stage of decomposition, it will be hard to estimate an accurate time of death. In this case, the forensics experts may only be able to estimate the time of death to within a couple of years. If a body is recovered from fire, water, or ice, it will also be difficult to give an accurate estimate of the time of death. A body recovered from ice will be more well preserved in that bacterial degradation will be slowed by the cold temperature. A body found in fire will likely be hard to identify and will have little microbial life to examine. Lastly, a body recovered from water will be bloated and will have been exposed to many other microbial factors that must be taken into account before time of death can be accurately estimated.

[Figure 1]The five stages of decomposition:Fresh, Bloat, Putrefaction, Fermentation, and Skeletal.[1].

Putrefaction

Include some current research in each topic, with at least one figure showing data.

Butyric Stage

Include some current research in each topic, with at least one figure showing data.

Conclusion

Overall paper length should be 3,000 words, with at least 3 figures.

References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

Edited by student of Joan Slonczewski for BIOL 238 Microbiology, 2009, Kenyon College.