Justin Salter & Ariana Castro

Scarlet Fever

- caused by the a spherical gram positive baceria called Streptococcus pyogenes,which causes many other human diseases such as impetigo, strep-throat, and superfical skin infections. The reason that scarlet fever is the disease, and not one of the other, is because once the person is infected with streptoccus pyogenes, it will cause streptococcal pharyngitis, which will then release an erthrogenic toxin, which is how scarlet fever occurs.
File:Streptococcus pyogenes 01.jpg
File:Streptococcus pyogenes 01.jpg

photo source: for Disease Control and Prevention's Public Health Image Library

How infection occurs-

Since scarlet fever is a disease of the upper respiratory system, therefore one can get infected by scarelt fever the same way as getting infected with the common cold. The bacteria is spread by fluids from the mouth and nose. For example, if a person sneezes or coughs, then the bacteria can become airborne,and infect others. Also, if someone touches a surface that is then touched by someone else, and touches their eyes, nose or mouth, they can get the infection.

external image strep.fig0.jpeg
photo source:http://www.textbookofbacteriology.net/streptococcus.html

The reason that the strain produces the toxin, is because of the toxin being lysogenized by a bacteriophage, which basicly means that the genetic information of a bacteriophage has been incorporated into the chromosome of the bacterium, so that the characteristics of the bacterium have been altered.


Scarlet Fever is usually not something that is heard about; most of us probably do not even know one person who has gotten the disease. During the 1850's through the early 1900's, there were scatterd cases of scarlet fever throughout the United States. Especially during the late 1800's, because of the amount of people that had scarlet fever, some of the schools in certain areas were shut down for a while. Not only did outbreaks occur in the United States, but also in Europe as well. Some may be wondering why scarlet fever was so widespread in the 1800's, and not now. There are many reasons why this may be, however one very good reason is that during the 1800's they were not as informed as we are now about sanitation, and how infections are aquired. Not until 1961 did Louis Pastuer demonstarte that microorganisms are present. 1876 was when Kock came up with his germ theory of disease. Poor living conditions can also be to blame for the outbreak of the disease.

Symptoms- There are certain symptoms that are associated with scarlet fever:

- a pinkish skin rash that spreads from the neck and face, to the rest of the body (looks like sun-burn).

- a redened sore throat

-fever of more than 101 degrees farenhiet.

-swollen tonsils and throat


-body aches



-loss of appetite


photo source:http://kidshealth.org/parent/infections/bacterial_viral/scarlet_fever.html

Diagnosis- Usually, if a person is exhibiting the symptoms above, then they will visit their local doctor or hospital. Once the pateint gets to the hospital, the health care provider will ask about the pateints symptoms, while also examining the pateint. Since scarlet fever can also look like the measels. there are certain tests that need to be done, that are very important. A throat culture can be taken from the pateint, and grown overnight to make sure that it is indeed a bacteria, and not a virus. If there are questions about the throat culture, a blood test can also be performed, which can distingiush between viral, and bacterial infections.

external image SuperStock_1612R-2183.jpg
photo source:http://wwwdelivery.superstock.com/WI/223/1612/PreviewComp/SuperStock_1612R-2183.jpg

Treatment- Before 1928, there were no that many things that could be done about scarlet fever. Perhaps this is why so many people died of the disease. Penicillin, the first antibiotic, was invented in 1928 by Alexander Fleming. Penicillin was found to be an effective antibiotic against scarlet fever, as well as other bacterial infections. Usually penicillin is given to the patient, which will stop the spread of the bacteria.
The patient is given penicillin through either by an injection, or orally. If the patient is allergic to penicillin, the the antibiotic erythromycin can also be administered. Usually the antibiotic is given for a total of 10-14 days, and it is important for the patient ot take the entire amount of medication that is prescribed, because one can feel well, without the infection actually having gone away. Once a person has been given the antibiotics on time, then they will usually make a full recovery. A person that has been infected with scarlet fever has a very low chance of ever contracting the disease again.

Prevention- There are certain things that one can do in order to aviod getting scarlet fever.

- Wash your hands frequently with warm water, and soap.

-Do not share dining utensils, such as drinking from the same cup or eating from the same spoon.

-Cover your mouth and nose, when you cough or sneeze.

The most probable reason that children get the disease more often then adults, is because they are more often in close contact with one another. Children that are playing together tend to huddle together, use the same toys, and forget to cover their mouth when coughing and sneezing.

external image index-main02.jpg
photo source:

-Though scarlet fever is a serious disease, thankfully was have discovered antibiotics that are able to kill streptococcus pygenes, and the patient can fully recover. It is true that with antibiotic resistance, that is now becoming a problem, we might have a problem with streptococcus pygenes, should it develop a resistence to current antibiotics. I however do not think that this is something that should be very worrisome, because scientist think that the severity of scarlet fever is not as strong as it was in the 1800's.

Literature Cited:
1.Choby B. Mar 1 2009. Diagnosis and Treatment of Sreptoccal Pharyngitis. American Family Physician. Vol 71 505-520.
2.Hahn Rg. May15 2009. Evaluation of poststreptococcal illness. American Family Physicain. Vol 71 1949-1954
3.Laval E. April 2009. Scarlet fever epidemic during year 1929 in Chile. REVISTA CHILENA DE INFECTOLOGIA. Vol 26. 168-172
4.Liang Ym. Dec 2008. Characteristics of Streptococcus pyogenes strains isolated from Chinese children with scarlet fever. Vol 97 1681-1685
5.Okamoto K. Dec 26 2008. A novel streptococcal leucine zipper protein (Lzp) binds to human immunoglobulins. Vol 377 1128-1134.
6. Tortora, Gerard J., Berdell R. Funke, and Christine L. Case. Microbiology An Introduction with CDROM. Boston: Benjamin-Cummings Company, 2006.

The second bacteria which causes upper respiratory tract infections is...
Any guesses? I'll give you a hint... it's Gram positive and Cocci

Staphylococcus Aureus

Gram-stain of staphylococcus aureus

This should look similar to any person that has any experience with microbiology. This is Staphylococcus Aureus, which is a Gram-positive bacteria, and if you are unable to tell by the name, it is coccus in shape, and are usually arranged in a grape like cluster. It is also facultative anaerobic which means it can grow with or without oxygen. Staph is able to thrive in harsh conditions such as high osmotic pressure and low moisture, which is why it can grow and live in the nose and on the skin, as well as foods like cured ham which is to salty for most competitors. This interesting yet scary organism has a fairly high resistance to heat, drying and radiation. Believe it or not, Staph is carried around naturally by many people on the skin or in the throat and nose. It is found normally on the skin and in the nose of 20-30% of healthy adults. This means it is not a transient bacteria and just because it is present on your skin, does not mean that it will necessarily be pathogenic, and in fact, it is harmless in the majority of cases. If it is however, it can cause infections in the skin and in any organ of the body, but usually infects the skin or respiratory tract. Staphylococcus can be broken down to its Greek roots. Staphyle, means a bunch of grapes, and kokkos, means berry. Staphylococcus Aureus literally means the golden cluster seed. This name was given to it for the golden colored clusters it has when grown on agar plates. The color may actually give it some protection from the antimicrobial effects of the sun.


Staphylococcus Aureus is a very important bacteria with a very important history. In fact, antibiotics as we know them today could possible not exist if it had not been for this bacteria. Although new developments, details, and discoveries are made all the time about this bacteria, here is a brief summary of the most important years and findings in it's over 100 years of history
In 1880, Staphylococcus Aureus was first seen in the pus from pyrogenic infections in humans. This discovery was made possible by Alexander Ogston who determined that this bacteria was Gram-positive and cocci.
In 1884, S. Aureus was first identified by Rosenbach as the pathogenic bacteria that caused wound infections and furunculosis.
In 1928, arguably one of the most important and influential discoveries in modern medicine occured. Sir Alexander Fleming went on a vacation after working on some S. Aureus cultures. When he returned, something was eating the bacteria he was working on! This mold that contaminated one of his culture plates was Penicillum which makes Penicillin. This discovery has been said to have extended the average life expectancy more than any other discovery.
in 1961, MRSA or methicillin-resistant staphylococcus aureus was discovered.
in 1999, Nov 22 to be exact, MRSA incidences have risen 12-fold since 1991. Also, 37% of all Staphylococcus Aureus infections were found to be caused by MRSA. VRSA or vancomycin resistant staphylococcus aureus is also now discovered in Scotland.

Sir Alexander Fleming


There are three different types of S. Aureus which are very important to know for your own personal safety and for the safety of those around you. Even though there are many different variations of this organism, the three mentioned below are the current dangerous types. Since this organism is well adapted... to adapt, it is possible that new types may emerge in our lifetime. Knowledge is power especially when it comes to this bacteria, because the more you know, the closer everyone is to understanding how to beat this once solved problem. Mutations have made some of these types harder to treat, and has brought the death rate to an alarming number an estimated 19,000 people a year in the U.S. die from an infection caused by the MRSA type.

Staphylococcus Aureus: This is the generic and common type of staph that was discovered in 1880. This type is usually easier to treat since it usually is not resistant to antibiotics. These cause minor skin infections that can usually be treated with over the counter antibiotic ointment. No doctors visit is necessary if the infection goes away. If that doesn't work, prescription oral antibiotics are the next attack plan. The most common antibiotic that is prescribed for this is Penicillin. If an abscess has grown, it must be surgically drained first. Only for the most serious life-threatening situations, intravenous antibiotics are administered. Before that is done, lab tests are compiled to determine which antibiotic will work the best against your specific infection. They can do this by the disk-diffusion method, which was preformed in our lab class. They take a lawn of the isolated bacteria, and test many different antibiotics. They then check to see which has the biggest zone of inhibition, and that is the antibiotic that gets prescribed to you.
The regular type of staphylococcus aureus Copyright Dennis Kunkel Microscopy, Inc. (www.denniskunkel.com).

Methicillin-Resistant Staphylococcus Aureus: This is a mutated form of staph that is commonly known as MRSA that was discovered in 1961. Apparently, an old bacteria can learn new tricks. This specific type kills 19,000 people a year which makes the swine flu look like a walk in the park. This type is resistant to the antibiotic Methicillin, as well as Penicillin, Amoxicillin, and Oxacillin. This "super bug" makes treating this more difficult due to the traditional methods of medicine being rendered useless. This type is most commonly contracted in hospitals especially by the elderly as well as anyone who is sick and their immune system in down. It can also be contracted through an open wound or a catheter. The CDC estimates that 12% of MRSA infections are community-associated which means it can be passed from person to person by skin contact, an injury, or poor hygine, even if you never went to the hospital. The good news is that it can only be spread when a person has an active MRSA skin infection. In some cases, it can even be contracted from sheets or workout equipment. MRSA typically causes mild skin infections which can be treated with careful skin care and certain antibiotics. On the other side of the spectrum, MRSA can also be almost impossible to treat and can become a life-threatening blood or bone infection and it can kill you in less than a week after the infection took place. Drastic times call for drastic measures, and when a MRSA infected person has no other options, amputations are sometimes the only treatment.


Vancomycin-Intermediate Resistant Staphlococcus Aureus/Vancomycin-Resistant Staphylococcus Aureus: These are combined as 1 type since they both are resistant to the same thing. VISA (not the credit card) and VRSA where discovered very recently in the year 1999. Vancomycin is usually effective in treating staph infections, but VISA is a little resistant to it, and VRSA is totally resistant against it. The problem with all of these new emerging types is that medicine as we new it is now just a thing of the past. In the war with these super bugs, it is like we are bringing knives to a gun fight. Fortunately, it is hard to get this type, and a patient must be in poor health, recently had MRSA, recently had Vancomycin, had tubes sticking out of thier bodies, and had a recent hospitalization. Although this type can be treated with other drugs, and is much less prominant than any other type, it is still scary to see staph's ability to mutate.


S. Aureus can cause a wide variety of illnesses which can range from mild ailments that require no treatment, to severe infections that can be quick and fatal. Anyone can get a staph infection, but you are more likely to get it if you are: a newborn infant, breastfeeding, have a chronic condition (cancer, diabetes, lung or vascular disease), inject drugs, have a skin injury, have any surgery or a post-surgical apparatus, or, if you have a weakened/compromised immune system, or are on immuno-suppressant drugs. Also a person who has just visited a hospital is at higher risk, because that is where most people contract a pathogenic form of staph which is called a nosocomial infection. Out of all bacteria, staph is one of the four leading causes of all nosocomial infections. More than 500,000 people a year come down with a staph infection in this way.

Since staph infections are more easily detectable on the skin, tell your doctor if you are excreting or draining pus, or have a red, swollen, and or painful area on your body, which usually occur around an area that has had an injury regardless of severity. Make sure to be persistent about getting a lab test, to prevent a misdiagnosis. The longer a staph infection lingers, regardless of the type, the worse it gets, and the harder it is to treat.

According to an article in Nature, people can be long term carriers of S. Aureus without it ever becoming pathogenic. This is important, because if it is found out how to keep staph from becoming virulent, then it can be figured out how to put that to clinical use. Just think of a shot your given or pills you take that make staph as harmless as a sleeping healthy infant. Hattie Gresham is a microbiologist at the University of New Mexico in Albuquerque, who has been studying how hosts can carry a pathogenic form of S. Aureus for 15 years without any problems or infections. As stated in the introduction, about 25% of healthy people have this bacteria permenantly in their nose. Astonishingly, 1% of people live healthily with MRSA.

""That means that the host has something that can keep the bacteria in check," says Gresham. She suspected that some component of human blood plasma was interfering with S. aureus communication." (5)

Skin Infections
The pathogenic form of staph can cause: pimples, impetigo (a crusting of the skin), boils, cellulitis folliculitis (inflammation of the subcutaneous connective tissue, which usually can be seen by swelling and or redness), furnicles, carbuncles (abscess larger than a boil), scalded skin syndrome and abscesses, and mastitis (inflammation of the breast, which can cause the baby to become infected).
S. Aureus skin infection

Bloodstream/Organ Infections
The spread of a bacteria into the bloodstream and organs is known as sepsis. When staph is in the bloodstream or the organs, it is much more serious and much more dangerous. Sepsis can cause: staphylococcal pneumonia (leads to abscess formation in lungs), endocarditis ( infection of the heart valves that leads to heart failure), osteomyelitis (inflammation of the bones), and a widespread infection of the bloodstream (leading cause of shock/circulatory collapse, which causes death in burn patients)
Although this baby has a bloodstream staph infection it is hard to visually see one. this baby has red skin it is not always a syptom. Don't worry no babies where harmed in the taking of this photo:)

Toxin Poisoning/Pyrogenic toxin superantigens/Enterotoxins
Food poisoning caused by staph toxin PTSA ( not parent teacher student association) can cause illness in the bowels, which usually lead to nausea and diarrhea which cause vomiting and dehydration. This happens because staph produces toxins or enterotoxins to be exact, and when they are consumed, the effects of it can be felt between 1-6 hours and can last from 1-3 days. Enterotoxin is produced and released when staph is allowed to incubate in the food, which is called temperature abuse. A population of about 1 million bacteria per gram of food is all thats needed to get a person very ill from this potent enterotoxin. Some high risk foods to avoid or limit, to prevent illness are custards, cream pies, and ham, but as long as the food is adequately refridgerated, you shold be fine. Oncethe toxin is present however, it can survive up to 30 minutes of boiling!!. Luckily, this can't be transmitted from person to person and your body fights it off with no medication needed. The leading cause of gastroentritis is due to intoxication from staph food poisoning.
Toxic Shock Syndrome only happens when PTSA's are consumed that grew when fermented (with little or no oxygen). TSS, is characterized by a sudden high fever, vomiting, diarrhea, and muscle aches. Then low blood pressure can occur which leads to shock and death. Occasionally a peeling sunburn like rash will accompany the other symptoms. The most common cases of this occur in women who use tampons.
Toxic Shock Syndrome caused by staph in a male


Diagnosis/Pathogenic Mechanism

When staph is just starting to develop, and symptoms are relatively minor, it is usually just visually diagnosed without tests. This has seemingly been a problem though due to the catastrophic effects it can have for a patient. Most minor staph infections can be treated with common antibiotics, or ointment, but once it gets past a certain point, it is much harder to rid the body of it. Doctors sometimes misdiagnose a staph infection for something else, and it can cause amputation or even death. It is important for a patient in question to ask to have a lab done, which is quick and relatively easy. For more serious cases, staph infections in the bloodstream require a lab to be detected. By doing this they can also establish what medication will work best.
According to an article in Science, a characteristic of staph is it's invasion of the bloodstream and it's ability to form abscesses. It seems that staph is well adapted to being a pathogenic bacteria. Also staph has the ability to cross the cells vascular basement membrane (extravasate) which appears to be very important in an organisms ability to be pathogenic. So how exactly does staph get past that membrane which should stop it in its tracks? Well a study was done and a correlation was found between the ability to extravasate, and the presence of a certain receptor. This receptor is for the basement membrane glycoprotein laminin. The pathogenic staph has similar laminin receptors which lets it in the cell, where as its noninvasive relative S. epidermidis did not. That means that the glycoprotein laminin receptor plays a role in this organisms pathogenic capabilities.
I couldn't find a picture for the glycoprotein laminin receptor, but this gives the general idea of how it would work



S. Aureus is such an amazing example of adaptation and survival of the fittest. Personally, I feel that this is direct evidence that evolution takes place even in less time than previously thought. This Gram-positive bacteria is not only interesting, it is science. Through this informational site, I have put a combination of different sources to make my own new product just like staph is doing at a phenominal rate. So with the unrefreshing reminder that something so small is outsmarting something so big, it is time to start planning a new attack. It is well known that this bacteria is pathogenic, but it isn't well enough known how dangerous it could be. With a death toll that is shockingly high, it is something that more people need to know about. Well, that is why I made this project about this specific subject... to spread knowledge. If people take the necessary precautions and practice proper hygine, it is putting less people at risk. So just like this bacteria can spread from a source and learn how to adapt, spread this source of knowledge so we can learn how to adapt, survive and prevent a pandemic

Literature Cited:

1. a variety of info used for the history of Staph was found on many sites found on this page with the actual information as well. It was in the format of a time line. History Timeline
2.Wikipedia Page On Staphylococcus Aureus
Wikipedia, the free encyclopedia
3.Staph Infection
Medical author: Melissa Conrad Stöppler, MD
Medical editor: William C. Shiel Jr., MD, FACP, FACR
1996-2009 MedicineNet, Inc.
4.Presence of Laminin Receptors In Staphylococcus Aureus
Author: JD Lopes, M dos Reis, and RR Brentani
Science, July 19 1985:
Vol. 229. no. 4710, pp. 275 - 277
DOI: 10.1126/science.3160113
Copyright © 1985 by American Association for the Advancement of Science
5.Microbiology: Tinker, Bacteria, Eukaryote, Spy
Author: Asher Mullard
Nature, May 13 2009
459, 159-161 (2009) doi:10.1038/459159a
6.Microbiology An Introduction
Author: Tortora, Funke, and Case 9th edition
2007 Pearson Education, Inc
pgs (332,751-752
7. VISA/VRSA: Vancomycin-Intermediate/Resistant Staphylococcus Aureus
Author: CDC
October 26, 2007
Division of Healthcare Quality Promotion (DHQP)
National Center for Preparedness, Detection, and Control of Infectious Diseases