Need help assisting with my Microbiology paper on staphylococcus aureus
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Staphylococcusaureusonthebodyandhumandisease.pptxStaphylococcus aureus on the body and human disease
Discovery of a microscopic pathogen
In 1880 a Scottish surgeon, Alexander Ogston, hypothesized that a microscopic germ was responsible for wound infections
He took a sample of pus from a patient, stained it, and under the microscope found Staphylococcus bacteria in enormous numbers
Cheek cell
Bacterial cells
Bacterial cells
White Blood Cell
Staphylococcus aureus
Staphylococcus aureus (Staph) is a Gram-positive cocci that calls our body home
An estimated 33% of the human population are colonized by S. aureus
It can be found living in the nostrils, ears, tonsils, and also on the skin such as the armpits, groin, and between the butt cheeks
What do these sites have in common?
While carrying S. aureus on the body can be harmless, it has become a leading cause of skin, respiratory, and bloodstream infections
The main cause of Staph infections
Highly contagious!
Gram + bacteria stain purple after a successful gram stain
Staphylococcus on the body and human disease
Staphylococcus bacteria have evolved to live in and on the bodies of animals, including the dry, salty conditions of the skin
For example, an estimated 100% of the population have Staphylococcus epidermidis living in their nose and on their skin
It is a close relative of S. aureus; however, it has a limited ability to cause disease
Fewer people carry S. aureus on their bodies, but it has many virulence factors that makes it a highly successful pathogen
Virulence factors are molecules produced by microbes that results in damage to your body
S. aureus uses its virulence factors to make you its food source!
Staphylococcus aureus virulence factors
S. aureus virulence factors include:
Coagulase enzyme clots our blood. Clotted blood hides the bacteria from our immune system
You can think of the blood clot as a protective net around the bacteria
A biofilm for large-scale attachment of cells to tissue and hiding from our immune system
A sticky netting that protects the cells
Hemolysin enzyme to destroy our red blood cells
Why would S. aureus want to destroy our RBCs?
Leukocidin enzyme to destroy our white blood cells
The yellow strands are the clot
Known skin, sinus, and mouth diseases caused by or associated with Staphylococcus aureus
Skin disease:
Folliculitis (pimples)
Swollen lymph nodes
Psoriasis
Eczema/Rosacea/ Impetigo
Ear infections
Sinus and mouth disease:
Allergies and congestion
Postnasal drip
Sore throat
Cavities and gingivitis
S. aureus location on the body is associated with nearby pimples and rashes
In my experience, people who have pimples or a skin rash around the nose or above the mouth are more likely to harbor S. aureus in their nostrils
If the pimples are below the lips or on drool lines, the bacteria may have come from the mouth/tonsils
Those who carry the bacteria in their ears are more likely to see pimples on their cheek bones, jaw line, and shoulders
Thigh and butt acne may indicate colonization of S. aureus in those areas
Back acne or forehead acne may be a result of S. aureus draining from the scalp while showering/sweating
Nasal S. aureus?
Mouth/tonsil S. aureus?
Ear S. aureus?
S. aureus has also been shown to cause or be associated with more severe, chronic diseases:
Staphylococcus aureus and chronic disease
You can find a full list of diseases caused by or associated with S. aureus at:
https://www.reddit.com/r/Staphacne/
Hair loss due to infection
If hair loss/thinning is being caused by S. aureus, the location of the hair damage may indicate the location of the active infection
Dogs, cats and other animals can carry S. aureus on their bodies as well!
It may be responsible for various skin and sinus diseases our pets get
A friend had 3 sugar gliders, and in 2017 they all became prone to diarrhea
A heavy concentration of Staph was found in the fecal matter of all 3 sugar gliders!
Staph can travel from the head to the intestines through nasal/throat secretions and has even been shown to colonize human intestines!
Other animals can carry Staphylococcus aureus
The yellow color on the plate indicates heavy S. aureus growth
S. aureus is a major pathogen among the immunocompromised
For immunocompromised persons, Staph can cause rapidly fatal disease
Life-threatening infections it causes includes:
Pneumonia is a major killer
Bacteremia when Staph grows and spreads in the bloodstream
Carditis is inflammation of the heart tissue
Osteomyelitis, an ancient infection, is a disease of the bone
What is made in the bone that makes this disease so deadly?
What makes each disease so deadly? If you are a carrier of S. aureus, why are you not getting these deadly infections?
Antibiotic-resistance in Staphylococcus aureus
Many antibiotics prescribed to treat Staph infections targets the cell wall, specifically Penicillin Binding Protein (PBP)
PBP links the layers of peptidoglycan together. By blocking PBP, a cell wall isn’t formed, and the bacteria dies
Some S. aureus have developed a resistance to antibiotics that target PBP
Disease-causing Staphylococcus aureus can be broken down into two categories:
Methicillin-sensitive S. aureus (MSSA) which is hurt by many cell wall antibiotics (amoxicillin, methicillin, etc.)
MSSA is “regular” Staph and the most common cause of Staph infections
Methicillin-resistant S. aureus (MRSA) is a type of Staph that is resistant to many antibiotics that target PBP
MRSA is a much less common cause of Staph infections
The antibiotic resistance is due to the mecA gene, which codes for a unique PBP (PBP2) that can’t be targeted by some of the antibiotics that kill MSSA
PBP
PBP2
MRSA and MSSA pathogenicity
1% of the overall US population are MRSA carriers
Healthcare workers are at greater risk of carrying MRSA
5% of healthcare workers are estimated to be carriers
MRSA is not more deadly than MSSA, but it is more challenging to treat
Antibiotics exist that fight MRSA infections! For example: antibiotics that stop bacteria from building proteins (Doxycycline/Azithromycin)
MSSA is responsible for more infections and deaths per year than MRSA!
Why does MSSA kill more people per year than MRSA if both are equally deadly?
Treatment for Staph infections in a hospital
At hospitals, Vancomycin is the antibiotic of choice to treat severe Staph infections
Vancomycin stops cell wall building, but it doesn’t specifically target PBP
Neither MSSA nor MRSA have developed a complete resistance to Vancomycin
The nasal Staph that caused my cystic acne was killed by Vancomycin (VA 30)
How will you detect for the presence of Staphylococcus aureus?
The mannitol salt agar (MSA) test that is commonly used for detecting and differentiating the growth of Staphylococcus bacteria
Staphylococcus epidermidis is a common skin microbe and is not associated with causing disease
Staphylococcus aureus can also be found on the body and is a major human pathogen
Sodium chloride is used to detect Staphylococcus bacteria. There is a high concentration of salt in the MSA test that kills most bacteria
Staphylococcus grow well because they have evolved to handle the salty environment of the human skin
Mannitol is used to differentiate the Staphylococcus that grow. It is a sugar that only some species can use for energy production
S. aureus can eat mannitol for energy, releasing acid
S. epidermidis is unable to eat mannitol, and the pH of the plate stays neutral
Phenol red is the pH indicator in the media
Phenol red is red at a neutral pH and yellow at an acidic pH
The bacteria will be grown at body temperature (98.6 F) for 48 hours
Staphylococcus aureus carriage test
You are going to test your nostrils, ears, and tonsils for the presence of Staphylococcus aureus
Day two:
Look for yellow colonies or a yellow environment to indicate carriage of Staphylococcus aureus
White colonies without the yellow color change are Staphylococcus epidermidis
Day one:
Each student needs 3 sterile cotton swabs, 1 large Mannitol Salt Agar plate, 1 small MSA plate, and two small strips of parafilm (6 squares of it total)
Divide your large plate in half and label one half for your ears and the other half for your nostrils
Write your name on the plate so you can easily find it next class period
Rub 1 cotton swab in and around both ears, then thoroughly rub that on the entire one half the plate
Rub the other swab inside both of your nostrils and repeat on the other half of the plate
Cover the rim of your plate with parafilm to prevent the media from drying out
We will incubate the plates at 37 Celsius for 48 hours
Testing for tonsil carriage of S. aureus
You will bring the mini MSA plate, cotton swab and a small strip of parafilm home (or to the school bathroom) to test your tonsils for S. aureus presence
Bring the inoculated plate to the next class and we’ll grow the bacteria at body temperature
We’re going to collect Kahoot data on tonsil, ears, and nostrils carriage and include it in our Staph research papers
Instructions for the tonsil swab:
Label the base of your small plate with the environment tested and your first name (write small!)
Use a mirror and bright light (phone) to find your tonsils. Use the swab to rub and press against one tonsil, then rub and press the same swab on your second tonsil. You’ll then rub the swab over the entire mini MSA plate
Try not to contaminate the plate and swab and be mindful of the gag reflex!
If you don’t have tonsils, swab the area where your tonsils were!
Wrap the plate with parafilm, put it in your bookbag, then bring it to our next class
If you don’t have parafilm, seal it in a sandwich bag/aluminum foil
Elimination of Staphylococcus aureus from my nostrils
In early 2014, I started frequently getting nose sores inside my nostrils (so painful).
Knowing that I was a nasal carrier of S. aureus, I found a publication from Northwestern University that suggested Triple Antibiotic Ointment (Neosporin) was an effective way to kill nasal S. aureus
I applied the ointment 2x a day for 20 days into my nostrils with a cotton swab
I tracked my progress with mannitol salt agar plates
After 20 days of treatment, I completely decolonized my nostrils of Staph
I haven’t gotten a nose pimple since!
Elimination of that bacteria also, unexpectedly, got rid of my pimples
I had been getting regular acne since I hit puberty
My nasal decolonization experiment
Plate 1: 5 days of nasal Neosporin treatment
Plate 2: 10 days of nasal Neosporin treatment
Plate 3: 20 days of nasal Neosporin treatment
Family members can be carriers of Staphylococcus aureus
Father
Mother
Sister
My sister and I were sterile when we left the womb. How do you think we both became carriers of Staph?
Colonized by Staph again in May 2015
I was Staph-free (and pimple-free) from August 2014 through May 2015
I had stopped applying Triple Antibiotic Ointment to my nostrils because I consistently tested negative
In May of 2015, my face started to get oily, my nose became chronically itchy and congested, and I starting breaking out with cystic acne
I found I was again colonized by S. aureus in my nostrils, and it was now living in my ears!
S. aureus from ears
Trial and error to kill the 2015 Staph
It took almost a year of trial and error to effectively control this new Staphylococcus aureus that was living in my nostrils and ears
Some strains (versions) of S. aureus are stronger than others. Neosporin was not able to fully kill this new Staph
2016: Cleaning my nostrils and ears with rubbing alcohol
I learned that regularly cleaning my nostrils and ears with cotton swabs soaked with 70-90% isopropyl alcohol was able to effectively manage the presence of Staphylococcus aureus
I became colonized again (!) in Fall 2017
While performing this experiment with students during Fall 2017, I discovered I was colonized again by S. aureus in my nostrils
I’m pretty careful with touching my nose, and I’m not sure how I acquired the bacteria
October 9th 2017 I was not colonized by S. aureus in my nostrils (right) nor ears (left)
On October 13th I had S. aureus living in my nostrils
My Staphylococcus aureus under the microscope
1000x magnified Gram stain of my nasal Staph aureus (purple cocci). Anyone speculate what the pink material is that is surrounding the bacteria?
Using chlorhexidine to kill nasal Staph
Alcohol evaporates quickly, and I don’t believe it lasted long enough in my nose to effectively kill S. aureus
I tried a new method to kill my nasal Staph: chlorhexidine (Hibiclens)
For two days, I cleaned my nostrils with a cotton swab wet with chlorhexidine
After those two days, I had fully killed the S. aureus in my nostrils (right)
Killing my mom’s nasal Staph with chlorhexidine
After learning how effective chlorhexidine was, I asked my mom to perform an experiment
She had previously tested positive for nasal Staph, but she hadn’t treated it with anything
The left side of the plate was before she disinfected her nostrils with chlorhexidine
A lot of S. aureus grew
The right side of the plate are her nostrils 5 minutes after applying chlorhexidine
In 5 minutes, my mom was able to fully get rid of her nasal Staph!
My current routine
I now regularly clean my nostrils, ears, and body with chlorhexidine
I have not tested positive in my nostrils/ears since October 2017
The following link has the decolonization method that I follow: https://www.reddit.com/r/Staphacne/comments/428wtm/healthyalmonds_ears_and_nose_method/
Staphylococcus aureus decolonization methods
Removal of S. aureus from the body has been shown to be an effective way to prevent Staph infections
Established nasal decolonization methods include:
Mupirocin (Bactroban)- antibiotic that stops the bacterial ribosome from building proteins
Povidone-iodine nasal swabs- it’s a halogen
How do halogens kill?
Nozin- uses alcohol to kill nasal S. aureus
Alcohol breaks apart the plasma membrane of bacteria
Recommended skin decolonization methods include:
Bleach baths contains chlorine, a potent free radical generator
Chlorhexidine body wash (Hibiclens)
How does this antiseptic kill?
Why I regularly clean my body with chlorhexidine
In January 2018, I discovered I was colonized by S. aureus in two areas I never suspected; my belly button and my scalp
I was able to immediately kill my navel Staph with chlorhexidine
Using Hibiclens as a shampoo, with time, I was able to effectively kill my scalp Staph
My latest challenge: killing my tonsil Staph
At the end of 2018, I learned my tonsils were persistently colonized by Staphylococcus aureus
Makes sense since it’s warm, moist, and nutrient-rich
Nutrient-rich because the food/drink all hits my tonsils before reaching my stomach
My tonsils looked fine, and were not swollen or inflamed
Tonsil colonization by S. aureus has been shown associated with frequent sore throats as well as skin and body-wide diseases!
How often do we clean our tonsils?
Latest challenge: killing my tonsil Staph
Tonsils plays a role in providing mouth and throat immunity
If colonized by Staph, your immune system is likely keeping the bacteria from causing serious disease
However, bacteria can flourish in little crevices (crypts) in the tonsil, resulting in disease
Tonsil stones may develop in a crevice, and it can contain millions of bacterial cells!
Tonsil stones are a known cause of halitosis (bad breath)
Latest challenge: killing my tonsil Staph
I tried multiple antiseptics to rid my tonsils of S. aureus
Things I tried that didn’t work
Swishing mouthwashes (with different active ingredients, including chlorhexidine) around the back of my throat
Hydrogen peroxide as a throat wash
Ridding the tonsils of S. aureus
After swishing mouthwashes failed to rid my tonsil Staph, I continued using mouthwash but also focused on pushing out every possible tonsil stone from my tonsils
Some stones only appeared after I pressed on my tonsils with a cotton swab
Eventually, I started pressing cotton swabs soaked with mouthwash against my tonsils
I wanted the liquid to help push out tonsil stones that were deeper in my tonsil crypts
This released even more stones!
Ridding the tonsils of S. aureus
One day, while cleaning my tonsils, I pulled back my left anterior pillar to see if there were any stones hiding behind it
There was a hidden tonsil pocket containing a big tonsil stone
S. aureus can be removed from the tonsils (2019)
After removing the mother lode of tonsil stones in early June 2019, I had tested my tonsils multiple times for the presence of S. aureus
That stone was the main home of my tonsil Staph, and by removing it I had temporarily decolonized my tonsils of that bacteria! ( the bacteria unfortunately came back )
I now regularly swish mouthwash towards the back of my throat and semi-regularly soak a cotton swab in mouthwash and clean my tonsils with it
I use one swab per tonsil
Xylitol, a common sweetener in chewing gum, and chili powder, has been shown to hurt Staphylococcus aureus
Antiseptics that kill my tonsil Staph
While I still harbor the bacteria on my tonsils, I’ve learned of multiple antiseptics that can keep the bacteria at bay
There is no growth when the S. aureus is exposed to the following antiseptics:
1. H202. Hydrogen peroxide
2. Chlorhex. Chlorhexidine
3. Cetyl P MW. Cetylpyridinium chloride mouthwash
4. FL MW. Fluoride mouthwash
S. aureus carriage data from students between Spring 2017 and Spring 2020
| Spring 2017 through Spring 2020 students | Yes | No | Percentage of students that answered yes |
| Colonized by S. aureus | 411 | 143 | 74% |
| Colonized by S. aureus in the nostrils | 233 | 286 | 45% |
| Colonized by S. aureus in the ears | 332 | 207 | 62% |
| Colonized by S. aureus in the tonsils/throat | 88 | 25 | 78% |
