What is pathology? Pathology is the study of disease. Disease is caused by toxins that are released by bacteria. There are two types of these toxins that bacteria produce. Exotoxins are created by some Gram-positive bacteria which they release directly into their environment. An example of a bacteria that produces this toxin is Clostridium tetani which causes tetanus, a disease that affects skeletal muscle fibers.[1] Endotoxins are made of lipids and carbohydrates instead of proteins. This type of toxin is released by Gram-negative bacteria when the cells die. An example of a bacteria that releases this type of toxin is E. coli. Bacteria also cause disease by secreting digestive enzymes on body cells which kills them. This allows for the microbes to grow rapidly as long as nutrients are provided.
Antibiotic Resistance
Antibiotic Resistance is when a population of pathogenic bacteria evolve in such a way that antibiotics no longer have an effect on them. First off, antibiotics disrupt regular cellular processes within bacteria. Some antibiotics such as penicillin make bacteria unable to repair their cell walls, this means that osmosis becomes irregular and the cell dies. Antibiotics are made from fungi and some bacteria.Penicillin, a popular antibiotic, was discovered when Alexander Flemming left a culture of staphylococci open for a few days. He returned to find that the bacteria had grown all over the dish except for around a spot of mold that had grown.[2] Antibiotic resistance is a huge threat for modern medicine. Resistance can develop by a mutation that gives a bacterium resistance to a certain antibiotic which is then spread throughout a given population of bacteria through conjugation.
Historical Bacterial Outbreaks
The Plague of Athens is a historical event that isn't a well known epidemic case. The outbreak was in Athens during the summer of 430 B.C.E. which lasted two years. The cause of the epidemic is linked to the Peloponnesian War. At the time, Athens was under attack by Sparta, this forced citizens inside the city walls to live in close quarters with poor hygiene. Similar conditions also lead to the black plague epidemic in Europe many years later. The mortality rate was 33% the first time and the second outbreak four years later was 26%. The first outbreak occurred in the summer, the warm humid climate created a perfect environment for the contagion to multiply. What bacteria/virus that caused this outbreak is still up for debate. This is one reason I found this case so interesting. The accounts of Thucydides, a Greek historian, suggest that the plague could have been a mixture of diseases and not just one. The symptoms recorded as a fever, inflammation of the eyes, redness of the tongue and throat and fetid breath. After these symptoms coughing and vomiting would occur. The skin would also have blisters and sores, although he did not specify where. After 7 to 9 days the sufferer would die. The bubonic plague is one of the leading theories although some discredit it. Scientists have suggested that the outbreak could have been caused by Typhus of Typhoid fever as well while others disagree. When compared with diseases of today and the last couple hundred years, some scientists think that the disease could have been a type of bacteria similar to the bubonic plague that has gone extinct. This would explain why scientists have had a difficult time figuring out exactly what type of bacteria caused the outbreak. Viruses were ruled out as the cause because animals in the area also became infected. [3]
Remains of Victims of the Plague of Athens
http://www.toptenz.net/wp-content/uploads/2009/05/plague-of-athens.jpg
The Great Plague of London was one of the last major outbreaks of the bubonic plague in England. The plague took place from 1665 to 1666. When the plague started the nobility left for their estates far from London. Sir Isaac Newton was someone who fled to the countryside during this outbreak, and there he developed his theory of universal gravitation. An interesting thought to entertain is whether Newton would have not discovered the law of gravity if it had not been for the plague. Over 100,000 people died as a result of this bacterial disease. The symptoms of the bubonic plague are gangrene, chills, high fever, swelling of the lymph glands and sometimes skin discoloration. The plague spread from fleas found on rats to humans. Since the disease is bacterial, antibiotics such as doxycycline are administered. Outbreaks of this particular disease is quite rare in today's world. The reason that the disease was prevalent in the past was because of poor sanitation and rodent problems. Today's society also has better medical protocols, patients that have this disease are usually quarantined and cared for. There have been a few isolated incidences in the United States but the plague can still happen in countries such as India where sanitation is not as good.[4][5]
http://upload.wikimedia.org/wikipedia/commons/thumb/1/1e/Great_plague_of_london-1665.jpg/220px-Great_plague_of_london-1665.jpg
-Kyle-
Sources:
1.http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/tetanus.pdf
2.http://www.ideafinder.com/history/inventions/penicillin.htm
3.http://www.ancientgreece.com/essay/v/the_plague_of_athens/
4.http://www.britainexpress.com/History/plague.htm
5.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2235949/
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