Immunization Flashcards
What is immunization?
renders a person protected from an infectious disease
how does immunity happen naturally? how does it work?
exposure to the disease once, giving the immune system a memory of the disease
on second exposure, the adaptive immune system elicits a faster, stronger rxn
don’t become clinically ill
What are the two ways to provide immunity?
- passively
- actively
What is passive immunity?
the transfer of active humoral immunity (ready made Ab) from one person to another
what is an example of passive immunity involving infants?
maternal Ab transferred to fetus through placenta and breast feeding
How can passive immunity be induced artificially?
with high levels of humor (or horse) Ab (IgG)w specific for a pathogen or toxin transferred to non-immune individuals
can be used to counteract the effects of a toxin
when are 2 times passive immunity is used?
- when there is a high risk of infection and insufficient time for the body to develop it’s own immune response
- to reduce symptoms of ongoing or immunosuppressive disease
what are the benefits of passive immunity?
- faster than active
- protects during incubation period
what are the cons of passive immunity?
- short term solution
- can get disease after IgG gone
- not as effective as active
How is disease specific IgG created?
prepared by exposing humans or animals to the disease and than harvesting the Ab they make in response to disease
why is human IgG preferred to animal IgG?
- less rxns
- lasts longer (3 wks)
If you are using animal IgG what do you need to do before administering the dose?
test for hypersensitivity
what animal causes the least amount of allergic rxns with passive immunizations?
rodents/mice
What diseases do we have IgGs available for? Human (7) and horse (3).
Human: - Hep A - Hep B - Measles - Rabies - Rubella - Varicella - Tetanus Horse: - botulism - snake bite - black widow
What is active immunization?
introduction of immunity after exposure to an antigen
How is active immunity achieved?
Through vaccines; Ab created by the recipient in response to vaccine and may be stored permanently
How are active immunizations delivered?
series of injections over time
T/F: everyone who receives a vaccine for the chicken pox will be immune?
F; not everyone who receives a vaccination is immune.
What do vaccines usually contain?
agents that resemble disease-causing microorganisms
What are vaccines usually made from (4 materials)?
- weakened microbes
- killed microbes
- microbe toxins
- microbe surface proteins
What are the 3 different types of vaccines available today?
- live attenuated
- killed, inactivated
- toxoids
What materials do live attenuated vaccines?
- weakened microbes
How do live attenuated vaccines work?
weakened microbes replicated after administration to induce an immune response
What type of materials do viral vaccines usually use?
live viruses that have been chemically modified to decrease its virulence
how does chemically modifying live viruses benefit administration of live attenuated vaccinations?
doesn’t cause serious disease in healthy immune systems
Benefits of live attenuated vaccines?
- good response
- 1-2 doses for lifetime immunity
what live attenuated vaccine do we have to administer annually?
the flu vaccine
Who should not receive live attenuated vaccines?
Immunocompromised: pt that can’t tolerate even a mild form of the disease
What is the downside of live attenuated vaccines?
- can revert to more pathologic form and cause disease
- most contraindications
- pt can shed live virus after vaccine
- most S/E
List 5 types of live attenuated vaccines.
- intranasal influenza
- small pox (not since ‘72)
- Measles, mumps, rubella (MMRII)
- varicella vaccine
- varicella-zoster vaccine
how are killed, inactivated vaccines made?
by inactivating, or killing, the virus during the process of making the vaccine
are killed, inactivated vaccines made from whole bacteria/viruses or fractional antigenic components?
both
what are fractional, killed, inactivated vaccines made from?
protein or polysaccharides
what are the disadvantages of killed vaccines?
- higher dose than live
- multiple doses needed to build & maintain immunity
what are the advantages of killed vaccines?
can’t cause disease and are not contagious
What are conjugate vaccines?
sugar (polysaccharides) + protein of bacterium
what are examples of killed vaccines? (10)
- Tetanus, diptheria (Td)
- Tetanus, diptheria, acellular pertussis (Tdap)
- HPV
- influenza
- pneumococcal
- hep A
- hep B
- hep A/B
- meningococcal
- flu
why are polysaccharides important for conjugate vaccines?
necessary to elicit t-cell response; help immune system develop response
what are examples of conjugate vaccines?
- Pneumovax 23 (pneumococcal conjugated)
- many strains used
- Prevnar (protein conjugated)
why shouldn’t children
- coating disguises Ag
- hard to recognize Ag
- won’t develop immune response to it
what conjugated vaccine can you use with kids under 2 for pneumococcal immunity?
prevnar
Compare prevnar to pneumovax.
prevnar
- can use w. kids under two
- fewer strands (13)
What are toxoid vaccines?
prevent disease caused by bacteria that produce toxins
how are toxoid vaccines created?
toxins of bacteria are weakened
what metal helps to prolong absorption of toxoids?
aluminum; prolongs exposure to immune system and increases its response
what are examples of toxoid vaccines?
- tetanus
- diphtheria
how are vaccines administered?
- IM
- SQ
- PO
- intradermally
- intranasally
what is seroconversion? why is it used?
development of Ab in the blood that are measured after vaccination to see if immune; not all vaccines are successful
why isn’t seroconversion used sometimes?
not all vaccines produce Ab to measure
how are vaccinations normally administered? why?
in a series; each one boosting memory and immune response
T/F if you miss a dose during a scheduled vaccination series you are less immune.
F; just give next dose at next appointment.
You should not give vaccinations early if you can avoid it. Why?
previous dose may not have had time to acquire memory, there by decreasing its efficiency
why are some vaccines combine in one dose?
to decrease number of injections
what are the S/E of vaccines?
- inflammation at injection site
- malaise
- fever
- chills
- HA
- myalgia
- febrile illness
- seizures
- anaphylaxis
- somnolence
what s/e of live attenuated do the other vaccines not share?
possible development of mild case of disease vaccinating against
what are the contraindications of vaccinations?
- anaphylactic rxn
- immunodeficiency
- pregnancy
- encephalopathy after Dtap
what vaccines commonly cause anaphylaxis due to containing neomycin?
- inactivated polio vaccine
- MMR
- varicella
what vaccines contain egg protein?
- MMR
- influenza
what vaccines should be avoided with immunodeficient patients?
live attenuated vaccines:
- PO polio vaccine
- MMR
- varicella
What vaccines are especially avoided during pregnancy?
live attenuated vaccines
- MMR
- varicella
- influenza
What vaccines are allowed during pregnancy?
- inactivated influenza
- Tetanus-diphtheria (Td)
- Tetanus-diphtheria-pertussus (Tdap)
when should tetanus-diphtheria (Td) vaccine be administered during pregnancy?
if unimmunized or booster due
@ 0, 4, 6-9 months pregnant
when should tetanus-diphtheria- pertussus (Tdap) vaccine be administered during pregnancy?
if unionized to pertussis
After 20 weeks gestation
when should Dtap and Tdap be held from patients?
if they developed encephalopathy within 7 days after administration of previous dose
What are some examples of when vaccinations are not contraindicated?
- mild to moderate local rxns
- mild acute illness
- during Abx use
- prematurity
- family Hx of adverse rxn
- diarrhea
- breast feeding
what is the national vaccine injury compensation act?
compensates individuals who undergo injury from vaccines
what is a requirement of healthcare providers, under the national vaccine injury compensation act?
must report all events requiring medical attention within 30 days of a vaccination
only must describe injuries temporal relationship to vaccine
When do you give passive immunization?
- rapid response
- use when pt at risk for disease before normal vaccine would work
What are commonly given passive vaccinations?
- hep A
- varicella
- tetanus
- rhogam
what is rhogam? what does it do and prevent?
passive IGIV immunization given to Rh - mother
prevents Rh- mother from mounting an immune response to the Rh + child
prevents hemolysis in the new born
when would you give a passive and active immunization?
- Rabies (due to severity)
- infant born to Hep B+ mom
- Tetanus (if never finished original series)
What should be done after passive immunization (IgG) is given?
F/U with vaccination because passive immunity is short term solution
Research says giving active and passive immunity at the same time may not be a great idea… why?
potential for Ag in vaccine to bind to Ab in passive immunity, decreasing immune response
T/F if you are giving a shot for active and passive immunity they should be done in the same location on the body.
F; give them at different parts of body
Are infants born to mother’s with Hep B given a vaccine or IgG at birth?
both, they greatly reduce transmission
How many vaccines make up the original series for tetanus prophylaxis?
4
Pt presents with tetanus prone wound; their full vaccine series finished 15 years ago. How should you proceed?
Administed booster
Pt presents with tetanus prone wound; their full vaccine series finished 3 years ago. How should you proceed?
No further action needed
Pt presents with tetanus prone wound; the never finished their full vaccine series. How should you proceed?
Give complete series and immunoglobulin (active & passive)
Toxins are produced within 5 days and it takes
Pt presents with clean wound; they can’t remember if they finished their tetanus series. How should you proceed?
give complete series
Pt presents with clean wound; they finished their complete series of tetanus vaccinations 15 years ago. How should you proceed?
booster
