pathogen

Examples of pathogen in the following topics:

• Extent of Host Involvement

  • Host-pathogen interactions are the interactions taking place between a pathogen (e.g. virus, bacteria) and their host (e.g. humans, plants).
  • Host-pathogen interactions are the interactions that take place between a pathogen (e.g. virus, bacteria) and their host (e.g. humans, plants).
  • By definition, all pathogens damage their host to some extent.
  • The appearance and severity of disease resulting from the presence of any pathogen depends upon the ability of that pathogen to damage the host as well as the ability of the host to resist the pathogen.
  • Clinicians therefore classify infectious microorganisms or microbes according to the status of host defenses - either as primary pathogens or as opportunistic pathogens.

• WBC Function

  • The innate immune system is non-specific and refers to the general ability of the body to prevent pathogen entry and destroy pathogens that do enter the body.
  • Phagocytosis of pathogens.
  • It involves the binding of an Fc receptor to a tail on a pathogen, engulfing the pathogen, and using enzymes and free radicals inside the leukocyte to destroy the pathogens.
  • When pathogens are encountered, granule dependent apoptosis (a mechanism of cytotoxicity) may be induced in the pathogen by releasing perforins, granzymes, and proteaseases from their granules.
  • The adaptive immune system is specific to each pathogen on the basis of antigens, which are molecular components of pathogens that are used by leukocytes to recognize that specific pathogen.

• Innate Immune Response

  • A host is the organism that is invaded and often harmed by a pathogen.
  • Mammalian immune systems evolved for protection from such pathogens.
  • Components of both immune systems constantly search the body for signs of pathogens.
  • When pathogens are found, immune factors are mobilized to the site of an infection.
  • Features of the immune system (e.g., pathogen identification, specific response, amplification, retreat, and remembrance) are essential for survival against pathogens.

• Intracellular Pathogens

  • Not all pathogens are undesirable to humans.
  • In entomology, pathogens are one of the "Three P's" (predators, pathogens, and parasitoids) that serve as natural or introduced biological controls to suppress arthropod pest populations.
  • There are several types of intracellular pathogens.
  • Bacteria can often be killed by antibiotics because the cell wall in the outside is destroyed, expelling the DNA out of the body of the pathogen, therefore making the pathogen incapable of producing proteins, so it dies.
  • According to the prion theory, prions are infectious pathogens that do not contain nucleic acids.

• Plant Defenses Against Pathogens

  • Plants defend against pathogens with barriers, secondary metabolites, and antimicrobial compounds.
  • Pathogens are agents of disease.
  • Both protect plants against pathogens.
  • Additionally, plants have a variety of inducible defenses in the presence of pathogens.
  • Plants can close stomata to prevent the pathogen from entering the plant.

• Regulating Virulence

  • There are three main hypotheses about why a pathogen evolves as it does.
  • For example, if the host dies, the pathogen population inside may die out entirely.
  • Pathogen strains that kill the host can increase in frequency as long as the pathogen can transmit itself to a new host, whether before or after the host dies.
  • The evolution of virulence in pathogens is a balance between the costs and benefits of virulence to the pathogen.
  • These traits typically arise due to mutations, which occur more frequently in pathogen populations than in host populations, due to the pathogens' rapid generation time and immense numbers.

• Physical and Chemical Barriers

  • The innate immune response has physical and chemical barriers that exist as the first line of defense against infectious pathogens.
  • In the innate immune response, any pathogenic threat triggers a consistent sequence of events that can identify the type of pathogen and either clear the infection independently or mobilize a highly-specialized adaptive immune response.
  • Pathogens are killed or inactivated on the skin by desiccation (drying out) and by the skin's acidity.
  • Some pathogens have evolved specific mechanisms that allow them to overcome physical and chemical barriers.
  • Some of these include the low pH of the stomach, which inhibits the growth of pathogens; blood proteins that bind and disrupt bacterial cell membranes; and the process of urination, which flushes pathogens from the urinary tract.

• Pathogenicity Islands and Virulence Factors

  • Pathogenicity islands (PAIs) are a distinct class of genomic islands acquired by microorganisms through horizontal gene transfer.
  • Pathogenicity islands (PAIs) are a distinct class of genomic islands acquired by microorganisms through horizontal gene transfer.
  • They are incorporated in the genome of pathogenic organisms, but are usually absent from those nonpathogenic organisms of the same or closely related species.
  • These mobile genetic elements may range from 10-200 kb, and may encode genes contributing to the virulence of the respective pathogen.
  • The GC-content of pathogenicity islands often differs from that of the rest of the genome, potentially aiding in their detection within a given DNA sequence.

• Pathogenicity Islands

  • Pathogenicity islands (PAIs) are a distinct class of genomic islands acquired by microorganisms through horizontal gene transfer.
  • They are incorporated in the genome of pathogenic organisms, but are usually absent from those nonpathogenic organisms of the same or closely related species.
  • These mobile genetic elements may range from 10-200 kb and encode genes which contribute to the virulence of the respective pathogen.
  • Pathogenicity islands carry genes encoding one or more virulence factors, including, but not limited to, adhesins, toxins, or invasins.
  • Pathogenicity islands are transferred horizontally, this details some of the ways that occurs.

• Airborne Transmission of Disease

  • Airborne diseases are characterized by diseases that are transmitted through the air via the presence of a pathogen.
  • Airborne diseases are characterized by diseases that are transmitted through the air via the presence of a pathogen.
  • These pathogens can include both viruses and bacteria that are spread by coughing, sneezing, laughing, or through personal contact.
  • The airborne transmission that occurs utilizes small particles or droplet nucleithat contains these infectious agents or pathogens.
  • Often times, these airborne pathogens can result in inflammation in the nose, throat, sinuses, and the lungs.