The National Academies: What You Need To Know About Infectious Disease

The National Academies

What You Need To Know About Infectious Disease

Dysentery

Dysentery is an inflammation of the colon characterized by frequent, watery stools, often tinged with blood and mucus. Dysentery is usually caused by one of two different organisms—a bacterium, Shigella, or an amoeba, Entamoeba histolytica. Bacillary dysentery is more common in the developed world, while amoebic dysentery more frequently occurs in tropical areas with poor sanitary conditions. Poor hygiene is the most common cause of dysentery but it can be spread by tainted food, contaminated water, and exposure to human feces (such as changing diapers).

Symptoms
Symptoms of bacillary dysentery, a milder form of the disease, usually appear between 1 and 3 days after an individual is infected. It typically begins with a stomachache, followed by diarrhea and fever. (Children less than two years old may develop severe infections and should be monitored carefully.)

Amoebic dysentery is more serious and presents with a wider range of symptoms that develop at least 2 to 4 weeks after exposure. Symptoms include fever, chills, nausea, and vomiting; watery diarrhea with mucus and blood; painful bowel movements; fatigue; and intermittent constipation. If untreated, the amoeba can break through the intestinal wall, spread into the bloodstream, and infect other organs, although this is very rare.

Treatment
Because vomiting and diarrhea can lead to dehydration, individuals with dysentery must drink plenty of fluids. If an analysis of a stool sample shows that bacteria are the cause, medication may not be prescribed unless symptoms are severe. In mild cases, symptoms typically dissipate on their own within a week. For amoebic dysentery, patients will likely be given a course of at least one antibiotic.

Prevention
Practicing good hygiene is the best defense against dysentery. Washing hands after using the bathroom and before preparing food is essential. If traveling to the tropics, where dysentery is common, drink bottled water, even when brushing your teeth, and avoid ice cubes, especially if you do not know what water was used to make them. Only eat food that has been cooked thoroughly.

Sources:
http://www.who.int/topics/dysentery/en/
http://www.cdc.gov/parasites/amebiasis/faqs.html
http://www.cdc.gov/nczved/divisions/dfbmd/diseases/shigellosis/#what
http://www.medicalnewstoday.com/articles/171193.php

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What do you know about infectious disease?

True or False: Not all microbes are harmful to humans.

  • Correct!

    Not all microbes are harmful to humans. In fact, many of them protect us, helping our bodies function properly and competing with harmful organisms in an eternal contest for habitable space in or on our bodies. Although the microorganisms that cause disease often receive more attention, most microorganisms do not cause illness.

  • Sorry, that’s incorrect.

    Not all microbes are harmful to humans. In fact, many of them protect us, helping our bodies function properly and competing with harmful organisms in an eternal contest for habitable space in or on our bodies. Although the microorganisms that cause disease often receive more attention, most microorganisms do not cause illness.

Infectious Disease Defined

Symptom

A subjective indication of the presence of disease or a departure from the body’s normal state of functioning. 

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