Majors

• The cell wall is made up of peptidoglycan, which gives the bacterial cell its shape.
• Communicable disease is a disease that can be spread from one person to another
• Non-communicable disease is a non-infectious disease that cannot be spread, lifestyle-related
• "Pathos" means disease
• Pathogen is a microbe that can cause a disease
• Pathology is the study of structural and functional manifestations of the disease
• Pathogenicity is the ability of the pathogen to cause a disease
• Pathogenesis is the mechanisms involved in the development of a disease
• Infection is colonization by a pathogen
• Microbe lands at a site where it is unable to multiply
• Factors affecting the presence of a pathogen at a site include:

  • Presence of antibacterial factors
  • Presence of indigenous microbiota (microbial antagonism)
  • Individual's nutritional and overall health status
  • Development of immunity from prior infection and vaccination
• Line of defenses include:

  • Agent (virulence of the pathogen, how it enters the body, number of organisms that enter the host)
  • Host (person's health and nutritional status)
  • Environmental factors (physical factors, availability of appropriate reservoirs, hosts, vectors, sanitary conditions)
• Terms related to infection:

  • Pathogen
  • Source of the pathogen/reservoir
  • Portal of exit
  • Mode of transmission
  • Portal of entry
  • Susceptible host
• Reasons why an infection may not lead to a disease:

  • Epidemiologic triad
  • Chain of infection
• Phases in the course of an infectious disease:

  • Incubation period
  • Prodromal period
  • Period of illness
  • Convalescent period
• Types of infections:

  • Localized infection
  • Generalized/Systemic infection
  • Acute infection
  • Chronic infection
  • Subacute infection
• Symptoms:

  • Symptomatic Disease
  • Asymptomatic Disease
• Signs:

  • Objective evidence of a disease
• Latent infections:

  • Primary infection
  • Secondary infection
• Steps in the pathogenesis of infectious disease:

  • Entry of pathogen
  • Attachment of pathogen to tissues
  • Multiplication of pathogen resulting in localized infection
  • Spread of pathogen to neighboring tissues or bloodstream
  • Evasion of host defenses
  • Damage to host tissues
• Virulence of microorganism:

  • Physical characteristics that enable microbes to be virulent
  • Attributes of the pathogen that help them escape host defense mechanisms
• Virulence factors include:

  • Attachment
  • Obligate intracellular pathogens
  • Facultative intracellular pathogens
  • Flagella
  • Exoenzymes
  • Toxins
• Mechanisms used by some pathogens to escape immune responses:

  • Antigenic variation
  • Camouflage
  • Molecular mimicry
  • Destruction of antibodies
• Bacteria have different shapes due to variations in their cell walls.
• Bacteria reproduce asexually through binary fission.
• Endospore formation is triggered when nutrients are scarce and environmental stressors such as heat, cold, radiation, and chemicals are present.
• Cocci are spherical bacteria, while bacilli are rod-shaped bacteria.
• The endospores can survive harsh conditions until they encounter favorable conditions again.
• Communicable disease is a disease that can be spread

  from one person to the other.
• Non-communicable disease is a non-infectious disease

  that cannot be spread, lifestyle related.
• Pathology is the study of structural and functional

  manifestations of the disease
• Pathogenicity is the ability of the pathogen to cause a

  disease
• Pathogenesis are the mechanisms involved in the development

  of a disease
• INCUBATION PERIOD – time between the arrival of the

  pathogen and the onset of symptoms
• PRODROMAL PERIOD – person feels out sorts but doesn’t

  experience actual symptoms; person feels like coming down

  with something but is unsure about it
• PERIOD OF ILLNESS – person experiences typical

  symptoms associated with that particular disease; This is

  where communicable diseases are easily transmitted.
• CONVALESCENT PERIOD – patient recovers or may have

  permanent damage from the destruction of tissues
• LOCALIZED INFECTION - infections located in one organ or

  organ system
• GENERALIZED / SYSTEMIC INFECTION - infection that

  involves 2 or more organ system
• ACUTE INFECTION – known to have a rapid onset and

  recovery; i.e. measles, mumps, influenza