2 MMR Flashcards
what is measles like
Highly contagious viral illness
measles structure
Paramyxovirus (RNA) structure
what is the leading cause of vaccine-preventable death in children
measles
how is measles inactivated
Rapidly inactivated by heat and light
how is measles transmitted
Respiratory transmission of virus
Transmission – respiratory airborne
where does measles replicate
Replication in nasopharynx and regional lymph nodes
what happens after exposure to measles
- Primary viremia (presence of virus in blood) 2-3 days after exposure
- Secondary viremia 5-7 days after exposure with spread to tissues
what is the incubation period for measles
Incubation period 10-12 days
what temperature does measles get to
Stepwise increase in fever to 103°F or higher
what are the early symptoms of measles
Cough
runny nose
what are the later symptoms of measles
14 days after exposure
> Rash: Begins on face and head, persists 5-6 days.
> Rash fades in order of appearance
measles reservoir
humans
what is the most contagious virus
measles
what is the heard immunity for measles
~95%
temporal pattern of measles
Peak in late winter–spring
who usually gets measles
children
Communicability of measles
4 days before to 4 days after rash onset
composition of measles vaccine
live attenuated virus
efficacy of measles
95% (range 90%-98%)
duration of measles vaccination
immunity – lifelong
vaccination of measles schedule
2 doses
what is mumps
acute viral illness
what is the structure of mumps virus
Paramyxovirus
RNA virus
how is mumps inactivated
chemical agents, heat, and ultraviolet light
how is mumps transmitted
Respiratory transmission of virus
where is mumps replicated
nasopharynx and regional lymph nodes
what happens after exposure to mumps
- Viremia 12-25 days after exposure with spread to tissues
- Multiple tissues infected during viremia
incubation period of mumps
14-18 days
early symptoms of mumps
- Nonspecific early symptoms muscle pain tiredness headache low-grade fever - Major salivary gland inflammation (parotitis) in 30%-40%
how many die from mumps a year
average 1
transmission of mumps
respiratory drop nuclei
mumps reservoir
humans
temporal pattern mumps
peak in late winter and spring
how many types of mumps antigens are there
one antigenic type
effect of there only being one antigenic type of a virus
easier to make vaccines
how long is mumps infectious to others for
Three days before to four days after onset of active disease
mumps vaccine composition
live attenuated virus (Jeryl Lynn strain)
mumps virus efficacy
87% (range 90-97%)
mumps vaccine immunity
life
why does mumps make you less fertile
inflammation of testicles
rubella virus type
togavirus RNA virus
how many rubella viruses are there
one antigenic type
how is rubella inactivated
chemical agents, ultraviolet light, low pH, and heat
how is rubella transmitted
respiratory
where is rubella replicated
nasopharynx and regional lymph nodes
rubella exposure effect
- Viremia 5-7 days after exposure with spread to tissues
- Placenta and fetus infected during viremia
rubella incubation period
14 days (range 12-23 days)
what are the early symptoms of rubella
low-grade fever etc.
- Rash 14-17 days after exposure
- Usually quite mild
Congenital Rubella Syndrome where does it affect
may affect all organs
what is the effect of Congenital Rubella Syndrome
- May lead to fetal death or premature delivery
- Severity of damage to fetus depends on gestational age
effect of infants and congenital rubella infection
Up to 85% of infants affected if infected during first trimester
Effects of congenital rubella
- Deafness
- Heart defects
- Liver and spleen damage
reservoir for rubella
humans
rubella transmission
respiratory (subclinical cases may transmit)
temporal pattern of rubella
peak in late winter and spring
when is rubella transmittable
7 days before to 5-7 days after rash onset Infants with CRS may shed virus for a year or more
composition of rubella vaccine
live attenuated virus (RA 27/3 strain)
efficacy of rubella
95% (range 90-97%)
duration of rubella vaccine
life
what is the recommended age for MMR vaccine
- 12 -15 months is the recommended and minimum age (more effective at 15 months)
- MMR given before 12 months should not be counted as a valid dose
- 2nd dose at 4-6 years
MMR adverse reactions
fever 5-15%
rash 5%
deafness rare
