~~~Lab 4: Sources Of Contamination And Infection~~~
~Introduction~
Airborne
microorganisms are usually carried on dust particles, although some (fungal
spores, for example) may be carried directly by air current. It is important
for microbiologists to be aware of the potential for contamination by airborne
microorganisms. Carefully observation of simple precautions dramatically
reduces the risk of contamination of the cultures.
Every
human is colonized by billions of microorganisms. These microorganisms, some of hitch are vital to be our wellbeing,
constitute our resident or normal microflora. Resident microorganisms are
nourished by the chemicals and moisture excreted by human body. In moist areas
such as the armpits, there are may be one million bacteria per centimeter cube,
on the drier skin of forearm, there may be 10000 bacteria per centimeter cube.
Resident
microorganisms are neither nonpathogenic or are prevented from infecting the
body by an array of mechanical and chemical defenses. Some resident microbes
are however opportunistic pathogens which may cause infection if the body’s
defenses are breached for example if the skin is broken.
Transient
microorganisms are picked up from our environment, for examples from faecal
contact or from soil and usually fail to become permanent skin residents. One
of the most important reasons for failure to gain permanence is that the
established residents are better able to compete for nutrients. Since transient
generally originate in other environment, they are poorly adapted to conditions
on the skin and usually disappear within 24 hours of arrival.
Microorganisms in the upper respiratory tract are either normal residents or
transients. As with the skin, the normal microflora largely consists of
nonpathogens opportunistic pathogens.
Large numbers of
transients enter the upper respiratory tract as we breathe or eat. They may
also come from our own hands or from improper sanitation during food
preparation. Regardless of their origin, most transients are nonpathogenic and
are quickly killed by various defenses arrayed against them.
~Objective~
To
determine the microorganisms in the air and from healthy human
~Result~
µ
Air
µ
Hands
µ
Ears
µ
Normal breathing
µ
Violent coughing
~Discussions~
Microbes are found everywhere from the
tallest mountains to the deepest part of an ocean on earth, but they are mostly
far too small to be seen by the naked eye. This activity allows students to
discover that microbes are found in a range of different habitats, to explore
the variety of microorganisms around us and to compare the range of
microorganisms that are found in different places. There are about 2,000
species of bacteria identified and even more where that they come from
including some pathogens, waffing in the air over.
In ours earth, the air also have the bacteria.
The bacterium is Bacillus cereus
that is a gram-positive, spore-forming bacterium. It causes two types of food
poisoning that are the diarrheal type by enterotoxin production in the small intestine
and the emetic type by toxin which is formed in food. It spores are both highly
resistant to a large number of stresses and very hydrophobic, which causes them
to adhere easily to food processing equipment. In our ear, the bacterium is Staphylococcus aureus. It is gram-positive,
coagulate-negative cocci that a part of our normal flora. Consequently, it is a
true opportunistic pathogen, as it requires a major breach in the host’s innate
defenses. The infections are associated with intravascular devices (prosthetic
heart valves, shunts, etc.) but also commonly occur in prosthetic joints,
catheters and large wounds.
There is also
a bacterium that is totally not cleaned when we wash ours hands. The bacterium
is Staphylococcus aureus. S. aureus
is a facultative anaerobic Gram-positive coccal bacterium. It is frequently
found as parts of the normal skin flora on the skin and nasal passage. S.aureus
is the most common species of staphylococcus to cause Staph infections and also
can cause a range of illness, from minor skin infections such as pimples, impetigo,
boils(furuncles), cellulitis folliculitis, carbuncles, scalded skin syndrome
and abscesses to life-threatening disease such as pneumonia, meningitis,
osteomyelitis, endocarditis, toxic shock syndrome(TSS), bacteremia and sepsis.
In
normal breathing, the bacterium is Streptococcus
pneumonia. That is a normal inhabitant of the human upper respiratory
tract. The bacterium can cause pneumonia, usually the lobar type, paranal
sinusitis and otitis media or meningitis which is usually secondary to one of
the former infections. It also causes osteomyelitis, leptic arthritis, endocarditis,
peritonitis, cellulitis, and brain obsesses. Currently the leading causes of
invasive bacterium disease in children and elderly. While in violent coughing,
the bacterium is called Haemophilus influenza. This bacterium is small (1 µm X 0.3 µm),
pleomorphic, gram-negative coccobacillus. It is a nonmotile, non–spore-forming,
fastidious, facultative anaerobe. Some strains of H influenzae possess a polysaccharide capsule.
The other encapsulated strains H influenzae occasionally cause invasive disease
similar to that of Hib. H influenzae type A (Hia) has been known to cause
invasive disease (eg, meningitis) clinically indistinguishable from that caused
by Hib. The nonencapsulated, or NTHi, strains cause mucosal infections, including
otitismedia, conjunctivitis, sinusitis, bronchitis, and pneumonia. Less commonly, these strains cause invasive
disease in children but account for half of the invasive infections in adults.
~Conclusions~
When we are walking into a room we can begin to stir up the microbial
soup that fills it. Without our thinking, one person can send about 37 million
bacteria into the air every hour, according to new research that measured
microbes suspended in a room when it was occupied and unoccupied. We are exposed
to the microorganisms. These microorganisms can be list as bacteria, viruses,
mould and fungi and are present around us all of the time. These bacterium are
also part of life's delicate balance and normally do not cause us harm.
Airborne microbes cause a lot of illnesses and diseases in humans that we do not
know.
Microorganisms in the air can make themselves in human or
animal body when a human or animal sneezes, or by the wind picking up the light
particles and blowing them where humans are. When a human sneezes
microorganisms leave the lungs at around 200 miles per hour. Some of the
microorganisms that are growing in the mucus in the respiratory tract enter the
air with the moisture particles that are sneezed out of the lungs. These
microorganisms can be breathed into the lungs of another person and that person
could get sick
~References~
No comments:
Post a Comment