Dysentery is the cause of 20% of deaths resulting from diarrhea . It stems from an infection of the intestines that leads to diarrhea with blood or mucus. The two main causes of dysentery are the Shigella bacteria (found primarily in western countries) and the amoebic parasite called Entamoeba histolytica (found in tropical areas) . In the United States, approximately 450,000 Shigella caused infections occur each year . Yet majorly, Shigella affects children in low to middle income countries, with about 99% of the cases occurring in those countries out of which 69% affects children. The leading reason for this is poor sanitation and overcrowding .
Dysentery-causing bacteria was first discovered by Kiyoshi Shiga in 1898, and in the following 100 years, researchers studied this, leading to the explication of the Shigella pathogen. Interestingly, this led to Shigella being one of the best models for studying invasive bacterial pathogens and has helped in our understanding of other bacterial pathogens as well .
Typically, both the amoebic and the bacterial dysentery are caused by poor sanitation. This could be due to the environment one is in or because of one’s personal poor hygiene [nhs].
According to the CDC, here are some of the ways that the Shigella bacteria can be spread (either by environment or personal):
- Getting Shigella on your hands and eventually in your mouth, through touching surfaces potentially contaminated with fecal matter of someone with Shigella bacteria infection.
- Through touching surfaces, bathroom fixtures, toys, diapers, etc.
- Changing the diaper of child with the bacteria
- Taking care of a person with the infection - cleaning up after them.
- Eating food that is made by someone who has the bacteria and if they cook with dirty hands
- Swallowing lake water or untreated swimming pool water
- Contaminated water (sewage or flood water contaminated)
- Exposure to fecal matter during sexual contact with someone with Shigella infection or who has recently recovered from it.
Ways to Reduce Risk
Shigella infections are easily transmitted and as such, it is important to maintain proper hygiene:
- Hand washing before preparing and eating food and before and after changing diapers of someone with the infection .
- Avoid swallowing lake and pool water .
- Stick to safe eating and drinking habits when traveling .
- Avoid sharing towels .
- Wash the laundry of an infected individual at the highest heat setting to kill the bacteria .
Consequences of Dysentery
It is a diarrheal based infection so symptoms will include :
- Stomach discomfort or cramps
- Feeling and/or being sick (nausea)
- High temperature
- General - mild 
- The infection tends to run for 5-7 days
- So rest and fluids may be all that is needed to prevent symptoms such as dehydration, if your general health is good.
- For children, they may benefit from rehydration solutions such as pedialyte.
- Severe cases of dehydration need medical attention, where individuals can receive salts and fluids intravenously (direct method).
- Antibiotics - severe cases
- According to Williams and Berkley’s literature review on antibiotic treatment for dysentery, fluoroquinolones, beta-lactams and cephalosporins are appropriate therapies, being the first and second lines of defense respectively .
- It is important to keep in mind that antibiotics often cause resistance in the bacteria if the medication is not taken appropriately. That is why it is important to fully go through the course of the medication even after symptoms subside.
- A randomized double blind trial conducted by Sharif et al., found a significant difference in duration of blood in diarrhea between those who were given probiotics and those who were given placebo, as well as in the days of hospitalization of patients in the treatment group vs. placebo group, with treatment group patients spending less time in the hospital .
- In general, the study found that the use of probiotics can be effective in reducing the duration of blood in the diarrhea .
Dysentery is clearly a serious condition with its unpleasant symptoms and with the way it affects numerous populations, especially children. While prevention is key, if you do get it, make sure that you stay hydrated, rest and observe your symptoms.
1. Sharif A, Kashani HH, Nasri E, Soleimani Z, Sharif MR. The Role of Probiotics in the Treatment of Dysentery: a Randomized Double-Blind Clinical Trial. Probiotics and Antimicrobial Proteins. 2017;9(4):380–5.
2. Dysentery [Internet]. NHS Choices. NHS; [cited 2021Mar5]. Available from: https://www.nhs.uk/conditions/dysentery/
3. Questions & Answers [Internet]. Centers for Disease Control and Prevention. Centers for Disease Control and Prevention; 2020 [cited 2021Mar5]. Available from: https://www.cdc.gov/shigella/general-information.html
4. Williams PC, Berkley JA. Guidelines for the treatment of dysentery (shigellosis): a systematic review of the evidence. Paediatrics and International Child Health. 2018;38(sup1).
5. Lampel KA, Formal† SB, Maurelli AT. A Brief History of Shigella. EcoSal Plus. 2018;8(1).
6. Shigella infection [Internet]. 2020 [cited 2021Mar5]. Available from: https://www.mayoclinic.org/diseases-conditions/shigella/diagnosis-treatment/drc-20377533