Pathogenic bacteria are bacteria that cause bacterial infection. This
article deals with human pathogenic bacteria.
Although the vast majority of bacteria are harmless or beneficial,
quite a few bacteria are pathogenic. One of the bacterial diseases with
highest disease burden is tuberculosis, caused by the bacterium
Mycobacterium tuberculosis, which kills about 2 million people a year,
mostly in sub-Saharan Africa. Pathogenic bacteria contribute to other
globally important diseases, such as pneumonia, which can be caused by
bacteria such as Streptococcus and Pseudomonas, and foodborne
illnesses, which can be caused by bacteria such as Shigella,
Campylobacter and Salmonella. Pathogenic bacteria also cause infections
such as tetanus, typhoid fever, diphtheria, syphilis and leprosy.
Koch's postulates are criteria designed to establish a causal
relationship between a causative microbe and a disease.
DISEASES
Each pathogenic species has a characteristic spectrum of interactions
with its human hosts.
CONDITIONALLY PATHOGENIC
Conditionally pathogenic bacteria are only pathogenic under certain
conditions, such as a wound that allows for entry into the blood, or a
decrease in immune function.
For example, Staphylococcus or Streptococcus are also part of the
normal human flora and usually exist on the skin or in the nose without
causing disease, but can potentially cause skin infections, pneumonia,
meningitis and even overwhelming sepsis, a systemic inflammatory
response producing shock, massive vasodilation and death.
Some species of bacteria, such as Pseudomonas aeruginosa, Burkholderia
cenocepacia, and Mycobacterium avium, are opportunistic pathogens and
cause disease mainly in people suffering from immunosuppression or
cystic fibrosis.
INTRACELLULAR
Other organisms invariably cause disease in humans, such as obligate
intracellular parasites that are able to grow and reproduce only within
the cells of other organisms. Still, infections with intracellular
bacteria may be asymptomatic, such as during the incubation period. An
example of intracellular bacteria is Rickettsia. One species of
Rickettsia causes typhus, while another causes Rocky Mountain spotted
fever.
BY LOCATION
Chlamydia, another phylum of obligate intracellular parasites, contains
species that can cause pneumonia, or urinary tract infection and may be
involved in coronary heart disease.
Mycobacterium and Brucella can exist intracellularly, though they are
facultative (not obligate intracellular parasites.)
TREATMENT
Bacterial infections may be treated with antibiotics, which are classified as bacteriocidal if they kill bacteria, or bacteriostatic if they just prevent bacterial growth. There are many types of antibiotics and each class inhibits a process that is different in the pathogen from that found in the host. For example, the antibiotics chloramphenicol and tetracyclin inhibit the bacterial ribosome, but not the structurally-different eukaryotic ribosome, and so exhibit selective toxicity. Antibiotics are used both in treating human disease and in intensive farming to promote animal growth. Both uses may be contributing to the rapid development of antibiotic resistance in bacterial populations. Infections can be prevented by antiseptic measures such as sterilizing the skin prior to piercing it with the needle of a syringe, and by proper care of indwelling catheters. Surgical and dental instruments are also sterilized to prevent infection by bacteria. Disinfectants such as bleach are used to kill bacteria or other pathogens on surfaces to prevent contamination and further reduce the risk of infection. Most bacteria in food are killed by cooking to temperatures above 73 ?C (163?F).
For more information view the source: Wikipedia
Recommended Test: Full GI Panel
Recommended Product: Freedom Cleanse Restore Parasite Cleanse
<< Back to Wiki