History:
There
are many factories along the eastern coast of North Carolina that produce
different types of spices from the cayenne pepper.
Most of the factories have
been in business for over thirty years and a problem had never occurred until
the spring of 2001. Over the time period of a few weeks several factory workers
were hospitalized. The outbreak had come from the factories, but more
specifically, what was being used in those factories. After some more research
was done they were able to pinpoint the route of the problem, the peppers,
because some local farm workers that had been hospitalized as well. Some more
digging was done, and come to find out all of the peppers originated from the
same town, in fact the same farm. Deans farm
in Wilson, North Carolina has been
in operation for many, many years and nothing like this had ever happened
before.
Once researchers were able to locate the source of the problem, they
still had a lot of work before them. Why was there a sudden outbreak? What’s
different about the peppers now? How do we treat this? Who is most likely to
come in contact with this new pathogen? These are just a few of the questions
that the researchers, doctors, and factory owners were faced with. It did not
take long before doctors were able to make some connections between each of the
patients. The main similarities found were burning sensations in the nose and
lungs. There were not as many people that handled the peppers directly and
those people broke out in hives on their skin. Medical professionals made note
that all of the patients had a normal blood pressure and had a fever averaging
to be 101. There were different tests performed so they could try to figure out
the best and most effective way to treat this new disease. The very first test
done was a white blood cell count to determine what type of pathogen was
causing this new disease. After determining that the pathogen was a bacterium
medical professionals then had to determine whether the bacterium was Gram
positive or Gram negative by doing a Gram stain. Adding different types of
stain to a sample and looking at it under a microscope to determine the type of
cell wall present helps for medical professionals to get a better understanding
of what type of bacterium they are dealing with. If the bacterium holds the
blue stain, crystal violet, then the bacterium is Gram positive indicating the
cell wall is thick. If the bacterium holds the red stain, safranin, then the
bacterium is Gram negative indicating the cell wall is thin.
This
experiment revealed to them that the bacterium is in fact a Gram negative. Now
that the type of bacterium is known it will help doctors narrow down different
methods for treatment.
Classification:
Researchers
were able to distinguish the type of cell wall this bacterium has, but before
moving in that direction let’s talk about what a bacterium is. A bacterium is a
prokaryotic cell meaning that it lacks a nucleus. The nucleus houses the DNA, and
without a nucleus the genetic material is floating freely in the cytoplasm.
Prokaryotic cells can be found everywhere and they reproduce
asexually, alone. Bacteria can be grown in a lab on nutrient agar plates and be
isolated for further examination under a microscope. By looking at it more
closely under a microscope, the structure and shape of the bacteria become more
evident, allowing for further classification. After determining that the
pathogen is a Gram-negative bacterium that grows on the surface of cayenne peppers
they were able to name this newly found pathogen and disease. The pathogen was
named
Sarciniabacilli piper,
‘sarcinia’ meaning the cells are arranged in a cluster, in the same way as
grapes, ‘bacilli’ means that the cells are rod shaped, and ‘piper’ is the Latin
word for pepper which is where the bacterium is found.
The pathogen is more
commonly known as Deans Burn. This name, while simple, is informative. It was
named after Deans Farm, where the peppers that carry the bacteria are produced
and the sensation you feel if infected with the bacteria. The disease, on the
other hand, is called pulmoexuro spiritus, ‘pulmo’ means lungs in Latin and
that is the primary area that is infected, ‘exuro’ is Latin for burning, which
is the sensation you feel once infected with the pathogen, and
‘spiritus’ means breath, the most common form
of entry. This disease is often referred to as Peppers Disease.
Disease:
The
pathogen can enter a host in two different forms; direct physical contact with
the peppers and it can be airborne for up to 48 hours. When contact is made it
can cause a large rash on the skin, which can produce burning and itching.
Since it is also airborne it is easy to become infected. The bacterium enters
in through the mucous membrane in your nose and continuously works its way down
until it reaches the upper respiratory system. This method has three different stages;
in the first stage the presence of the bacterium is only in the nose causing
irritation-there may be a slight burn. During the second stage, it has traveled
down into the back of the throat. As the mucous thickens the bacteria have more
nutrients and it becomes more active causing more irritation and a stronger
burning sensation. There may also be a slight fever during this stage. Finally,
as the disease progresses to stage three, the bacteria are at their happiest
and have the most nutrients. They have reached the lungs and are causing the
most damage. The burning is now excruciating and the fever has increased.
So far there has not been any deaths related
to this disease, but doctors are unable to guarantee that it will not cause
death. The pain that the patients are undergoing has been described as
unbearable and most rate it as an eight or nine on the pain scale.
One aspect
that doctors have noticed is that the disease seems to be contagious. One of
the patients came in contact with a family member, through the rash on his arm,
and it passed on to her.
Modes
of Infection:
Researchers
have pinpointed that there are two different ways that this bacterium can come
in contact with humans, by direct contact handling the peppers, or it can be
airborne for up to 48 hours. Since the factories are constantly bringing in
more peppers the bacterium continuously stays in the air; therefore, everyone
that is breathing in the air is coming in contact with the bacterium. Does this
mean that everyone that comes in contact with the bacterium will become
infected? The answer to this question is no because the host can be a reservoir
of infection-sites where pathogens are maintained. There are three different
types of reservoirs, but only one is relevant in this case. Human carriers are
asymptomatic, but can be infective to others.
Some of the factory
workers may be human carriers and never know they have the disease, but can
pass it to someone else. By directly coming in contact with the peppers this is
referred to as direct contact transmission. By handling the peppers the skin
can become infected, inducing the burning sensation that is commonly felt. The
most common form of transmission for this disease is vehicle because it is
airborne. By simply breathing through the nose or mouth you are breathing in
the bacterium, which may lead to infection.
Host
and Organ Cells:
After
identifying the pathogen as a bacterium and diagnosing the disease, it is now
time to understand where the pathogen is entering into the host. Researchers
have learned that the bacterium comes in contact with the host by direct
contact or through air. When you breathe in the infected air the bacteria enter
into your mucous membrane in your nose or mouth. The mucous membrane is a warm,
moist environment that is accommodating to the bacteria.
This
membrane supplies the nutrients that the pathogen needs to survive. As you
travel down the respiratory tract the mucous becomes thicker, equipping the
bacterium with more nutrients. This process is why there are three different
stages to Peppers Disease. Once it enters into the sinus cavity in your nose it
begins to absorb the mucous drying out the nose, generating the burning. As the
nutrients in the mucous are consumed the bacteria travels further down the
sinuses, into the throat, and progressively absorbs the nutrients, increasing
the burn present. Again, when the mucous has dried up it invades further into
the respiratory tract leading to the lungs. Due to the fact that the bacteria
thrive on the mucous, the cells affected in the lungs are limited. The
sermomucous glands and goblet cells are the primary target of the
Sarciniabacilli piper because the cells
release protein-rich mucin. This substance covers the epithelial
surface; epithelial cells form the structure of the lung, preventing it from
drying out. Once the bacterium reaches this area of the lungs and consumes the
mucous the burning sensation is severe.
Treatment:
Now
that medical professionals know the details about the infectious agent and the
primary targets of the pathogen, it is time to come up with a treatment plan.
The first thing done to target the pathogen was to try and find an
antibacterial that targeted a pathogen similar to the Deans Burn. After some
studying they came across a medicine that they thought would be effective. This
antibacterial drug is an Aminoglycoside called Tobramycin. Medical
professionals chose this drug for many different reasons, one of them being the
primary bacteria targeted- Pseudomonas aeruginosa. If you were to compare the two bacteria you would find these
similarities: Gram-negative, can be found in soil, water, or on the skin, and
it can target the lungs. Although there are some differences, Tobramycin seems
to be ideal. This antibacterial drug is effective against most Gram-negative
bacteria, which is crucial. Gram-negative bacteria have thin cell wall, but on
the outside of this wall there is an outer bilayer membrane made up of two
layers of leaflets. The inner layer is made up of phospholipids and proteins,
but the most outer layer is made up of lipopolysaccharide (LPS). When the outer
layer breaks apart it can trigger the LPS to become over excited and release
endotoxins into the body that may cause fever, vasodilation, inflammation, and
shock. By killing large numbers of Gram-negative bacteria there is a higher
risk of more LPS being released, causing more harm to the patient.
This
medicine has to be prescribed by the doctor and the primary method for
consuming the dug is using an
inhalation solution. To do this you will use a
nebulizer and an air compressor to breathe in the spray in through your mouth
and down into your lungs. This will take about 10-15 minutes to do, or until
the medicine is gone. The dosage on this drug for children six years and older and
adults is 300 milligrams twice a day for 28 days using the nebulizer. After you
have used the medicine for 28 days you will stop and wait 28 days before you
repeat the cycle. If you happen to come in direct contact with the
peppers and have hives on your skin it is important to treat this as well. The
medicine found to be most effective is
Mupirocin, also known as Bactroban. This
is a topical cream to apply a small amount to the hives three times a day for
3-5 days. While treating the infected host is important, it is also
important to treat the way the peppers are being grown at Deans Farm. The
bacteria start off in the water source that Deans uses to irrigate the fields.
You might be wondering why it doesn’t infect other plants, and the answer to
that is while in the water the bacteria lie dormant and do not begin to become
active until they reach the soil. The bacteria are facultative anaerobes
meaning that they can survive with and without the presence of oxygen. Although
they become active when they reach the soil, they do not begin to thrive until
they reach the surface of the cayenne pepper. By changing the water source used
to irrigate the fields you can help minimize the possibility of contaminating
the peppers. Another way to treat the fields would be to burn the fields that
the cayenne peppers are grown in. By burning the fields you are killing the
bacteria and preventing the spread to more peppers.
Although you may be able to
eventually eliminate the way the peppers become infected it is advised that the
farm and factory workers wear gloves while handling the peppers and wear a mask
to prevent them entering into your nose or mouth.
Efficacy
and Targets:
When
treating this disease medical professionals are going to be targeting something
the pathogen has or does that the host doesn’t have or do; this is known as
efficacy. Both humans and bacteria have ribosomes, the site for protein
synthesis, but they do differ. The ribosomes of a human are 80s and the
ribosomes of the bacteria are 70s, therefore targeting the ribosomes is an
effective way of hindering the bacteria without causing damage to the host. The antibacterial used to treat the disease inhibits protein
synthesis by irreversibly binding to the 30s ribosome of the bacteria. By doing
this you can cause the ribosome to mistranslate mRNA or cause premature release
of the ribosome, stopping synthesis.
Virulence
Factors:
The
Deans Burn releases extracellular enzymes that dissolve and absorb the mucous
throughout the mucous membrane. An extracellular enzyme is something many
pathogens secrete that enables them to dissolve structural chemicals in the
body and maintain infection.
Capsinase is an extracellular enzyme
that secretes Capsaicin, which is found in the cayenne pepper. When the
Capsaicin is released and comes in contact with the mucous membrane it causes a
burning sensation. The pathogen is mobile and once it enters into
your body it will continue to work its way down until it reaches the upper
respiratory system.
