Antiviral Drugs, Patterns of Disease, Epidemiology

  1. What are the mechanisms of action for antiviral drugs?
    • nucleoside and nucleotide analogs
    • enzyme inhibitors
    • interferons
  2. a.       Nucleoside and nucleotide analogs
    •                                                               i.      Targeting reverse transcriptase step
    • 1.       This family of drugs consists molsy of nucleoside nad nucleotide analogs
  3. Enzyme inhibitors
                                                                  i.      Two inhibitors of neuraminidase have been identifled—zanamivir and oseltamivir
  4. Interferons
    •                                                               i.      Interferons inhibit further spread of the infection; can be cytokines
    • 1.       Alpha interferon is for viral hepatitis infections
  5. a.       Antivirals for Treating HIV/ AIDS
                                                                  i.      HIV is an __; reproduction depends on __, which controls the synthesis of RNA from DNA
                                                                ii.      __implies that a drug is used to treat HIV infections
                                                              iii.      __ have been developed
                                                               iv.      Not all drugs that inhibit __ are __ or __
    1.       Non-nucleoside agents block RNA synthesis by other mechanisms 
    • RNA virus
    • reverse transcriptase
    • Antiretroviral 
    • Combinations of drugs
    • reverse transcriptase
    • nucleoside or nucleotide analogs
  6.                                                               i.      __ have proved especially effective when combined with inhibitors of __—example: indinavir
                                                                ii.      __ inhibt the enzyme that integrates viral DNA into the DNA of the infected cell
                                                              iii.      __ include antivirals that target the receptors that HIV uses to bind to the cell before entry
                                                               iv.      __ can prevent entry of HIV into the cell
    • Protease inhibitors
    • reverse transcriptase
    • Integrase inhibitors
    • Entry inhibitors
    • Fusion inhibitors
  7. a.       For an ID to occur, there must be a __. Next, the pathogen must __. Transmission is followed by __(__); then, __occurs
                                                                  i.      The extent of injury depends on the __
    • reservoir of infection as a source of pathogens
    • be transmitted to a susceptible host by direct contact, by indirect contact, or by vectors
    • invasion 
    • entry and multiplication
    • pathogenesis
    • degree to which host cells are damaged
  8. a.       Predisposing factor: __
                                                                  i.      __can be one (females get more UTIs)
                                                                ii.      __ (sickle cell in African Americans)
                                                              iii.      __ and __ have effect on incidience of ID
    1.       Temperate regions have higher incidences of respiratory disease
                                                               iv.      Inadequate nutrition, fatigue, age, environment, habits, lifestyle, occupation, preexisting illness, chemotherapy, emotions
    • makes body more susceptible to disease and may alter course of disease
    • Gender 
    • Genetic background
    • Climate and weather
  9. a.       Development of Disease
                                                                  i.      Development of disease follows stages. What are they?
    • 1.       Incubation: interval between initial infection and first appearance of signs and symptoms; depends on microbe and virulence
    • 2.       Prodromal: short period after incubation; early, mild symptoms of disease
    • 3.       Illness/ clinical: most severe signs and symptoms; number of WBCs may increase; if disease is not sufficiently overcome, the patient dies during this period
    • 4.       Decline: signs and symptoms subside
    • 5.       Convalescence: person regains strength 
  10. a.       Spread of infection
                                                                  i.      Reservoirs of infection: can be __ or __ that provides a pathogen with adequate conditions for survival
    1.       __: reservoir of human disease is human body itself
    a.       People with signs and symptoms of a disease may __; others can be __without exhibiting any signs or symptoms
    b.      Others carry disease during symptom-free stages—during __
    • living organism or inanimate object
    • Human reservoirs
    • transmit the disease
    • carriers 
    • incubation or convalescent period
  11. 1.       Animal reservoirs: What are zoonoses? 
    a.       Transmission can occur via many routes—direct contact, contamination fo food and water, air from contaminated hides, fur, or feather, insects, etc.
    2.       Nonliving reservoirs: __ and __
    • zoonoses are diseases that occur mostly in animals but can be transmitted to humans
    • soil and water
  12. a.       Transmission of disease: three principal routes—__(3)__
    contact, vehicles, and vectors
  13. Explain contact transmission.
                                                                  i.      Contact transmission: spread of agent of disease by direct contact, indirect contact, or droplet transmission
  14. Direct Contact transmission
    • 1.       direct transmission of an agent by physical contact between its source and a susceptible host; no intermediate; ex: kissing, sex, etc.
    • a.       To protect against this, gloves are used and other protective measures as well
  15. indirect contact transmission
    1.       occurs when the agent of disease is transmited from its reservoir to a susceptible host by means of a nonliving host; nonliving object involved in spread is fomite
  16. droplet transmission
    1.       microbes are spread in mucus droplets (droplet nuclei) that travel short distances; caused by coughing, sneezing, laughing, etc. 
  17. Explain vehicle transmission
    transmission of disease agents by medium like water and food; other media are body fluids, drugs, etc. 
  18. Waterborne transmission
    1.       pathogens are spread by water contaminated with untreated or poorly treated sewage
  19. Foodborne transmission
    1.       pathogens are generally transmitted in foods that are incompletely cooked, poorly refrigerated, or prepared in unsanitary conditions
  20. Airborne transmission 
    1.       refers to spread of infection by droplet nuclei in dust that travel more than 1 meter from the reservoir to the host
  21. Vectors
    animals that carry pathogens from one host to another, such as arthropods; can be done mechanically or biologically, 
  22. Mechanical transmission
    1.       passive transport of the pathogens on insect’s feet or other body parts
  23. Biological transmission
    1.       active process; arthropod bites infected person or animal and ingests some of the infected blood; the pathogens then reproduce in a vector and the increase in number of pathogens increases possibility that they will travel to other host; some reproduce in gut of arthropod and are passed with feces; toers reproduce in gut and migrate to salivary gland, where they are injected into a bite
  24. a.       Nosocomial infections don’t what?
                                                                  i.      __ has been introduced to include infections acquired in settings other than hospitals
                                                                ii.      8th leading cause of death in US
                                                              iii.      Result from interaction of several factors, such as __(3)__
    show any evidence of being present or incubating at the time of admission to a hospital

    Health care-associated infection

    • 1. Microbes in hospital
    • 2. Compromised status of host
    • 3. Chain of transmission I hospital
  25.                                                               i.      The __is a major reservoir for several pathogens
    1.       Certain normal microbiota of human body are opportunistic and present a particularly strong danger to hospital __
                                                                ii.      Some microbes become __
    1.       __become part of the microbiota of patients and hospital personnel and become more resistant to antibiotic therapy
    a.       People become aprt of the __ for __
                                                                                                                                          i.      Usually, if the host’s resistance is high, the new strains are not much of a problem
    • hospital 
    • patients whose defenses have been weakened by illness or therapy
    • resistant to antimicrobial drugs
    • Strains 
    • reservoir for antibiotic-resistant strains of bacteria
  26. a.       Compromised host: one whose __
                                                                  i.      Two principle conditions can compromise the host: __ and __
    1.       Intact skin is __; breakage in this first line of defense makes a person more susceptible to disease in hospitals; breakage can be burns, surgical wounds, trauma, etc. 
    • resistance to infection is impaired by disease, therapy, or burns
    • broken skin or mucous membranes, ad a suppressed immune system
    • impenetrable
  27.                                                               i.      Risk of infection also due to other invasive procedures, such as __, which may alter breathing and contribute to pneumonia and tracheotomy
                                                                ii.      __ provide a pathway for microorganisms in the environment to enter the body
    • administering anesthesia
    • Invasive devices
  28. a.       In healthy individuals, , WBCs called T cells provide __ by __, __, and __. WBCs called __develop into antibody-proucing cells, also protect against infection
                                                                  i.      Antibodies provide __by such actions as __(3)__
    b.      Drugs, radiation therapy, steroid therapy, etc. adversely affect the actions of __ and compromise the host. In addition, the AIDs virus destroys certain T cells
    • resistance to disease
    • killing pathogens directly
    • mobilizing phagocytes and other lymphocytes,
    • and secreting chemicals that kill pathogens
    • B cells 
    • immunity 
    • neutralizing toxins, inhibiting the attachment of a pathogen to host cells, and helping to lyse pathogens

    T and B cells
  29. I.                    Epidemiology
    a.       Identifying the __ of a disease is desirable so that it can be effectively controlled and treated; it is also desirable to understand the __ and __
                                                                  i.      The science that studies when and where diseases occur and how they are transmitted in populations is called __
    • causative agent
    • mode of transmission and geographical distribution of the disease
    • epidemiology
  30. 1.       John Snow identified and studied __
    2.       Ignaz Semmelweis examined __; ordered people to __
    3.       Florence Nightingale recorded statistics on __
                                                                ii.      All these people lowered incidence of disease
    • cholera
    • death rates due to lack of hygiene
    • wash their hands with chloride and lime
    • epidemic typus
  31. a.       Assembling and examining data is important as well for the __, which also makes knownign the site at which a host came into contact with the agent is known
    b.      Epidemiologists also worry about __, such as through chemotherapy and vaccines and determine the frequency of disease
                                                                  i.      Epidemiologists also focus on __
    • prevention of future outbreaks
    • controlling the disease
    • how effectively a disease is being controlled in a community
  32. Three types of investigations are conducted: __, __, and __
    descriptive, analytical, and experimental
  33.                                                               i.      Descriptive epidemiology entails __
    1.       Such a study is __

    2.       __ studies look forward
    • collecting all data that describe the occurrence of the disease under study
    • retrospective (looking backward after the episode has ended)
    • Prospective
  34.                                                               i.      Analaytical epidemiology does what? The study can be done in two ways:
    What are they?
    analyzes a particular disease to determine its probably cause

    • 1. Case control method: the epidemiologist looks for factors that might have preceded the disease
    • 2. Cohort method: the epidemiologist studies two populations—one that has had contact with the agent causing a disease and another that has not
  35.                                                               i.      Experimental epidemiology begins with a __about a certain disease; experiments to __ are then conducted
    1.       If a drug, a placebo is administered to one
    • hypothesis 
    • test the hypothesis
  36. a.       Case reporting
                                                                  i.      Effective way to establish the __; procedure that requires health care workers in report specified diseases to local, state, and national health officials
                                                                ii.      Provided epidemiologists with valuable leads regarding the origin and spread of AIDS
    chain of transmission
  37. a.       The __is a central source of epidemiological information in the US
                                                                  i.      Issues a publication called the Morbidity and Mortality Weekly Report
    1.       Contains data on morbidity, the incidence of specific notifiable diseases, and mortality, the umber of deaths from these disease
                                                                ii.      __ are diseases for which physicians are required by law to report cases to the PUS Public Health Service
    • CDC 
    • Notifiable infectious diseases
  38.                                                               i.      Morbidity rate is the __
                                                                ii.      Mortality rate is the __
    number of people affected by a disease in a given period of time in relation to the total population

    number of deaths resulting from a disease in a population in a given period of time in relation to the total population
Card Set
Antiviral Drugs, Patterns of Disease, Epidemiology