Measles, Mumps, Rubella Flashcards
Measles and mumps
negative strand RNA viruses, non segnmented, ss, naked
Rubella
positive strand RNA virus
M, M, and R all
cause systemic infection after initially infecting the URT
Measles and Rubella cause rashes
mumps no bumps
Measles is a member of what family
Paramyxovirus…so is mumps
Measles is extremely contagious
truth
How is measles different from the other paramyxoviruses?
Uses different receptors to gain entry into human host. Whereas the parainfluenzan and parap-neumo viruses attach to sialic acid, measleas attaches to immune cells CD46 and SLAM
Forms intracellular inclusion bodies KNOW THIS.
These are used in diagnosis
First event that occurs with negative strand RNA viruses
Transcription of messenger RNAs in order to then initiate protein synthesis
In + strand RNA
genome can automatically undergo translation
Measles infection generally occurs when
during childhood
Measles death usually due to
Bacterial pneumonia that occurs due to immunosuppresion from measles
What comes on first in Measles
Prodrome of fever, cough, conjunctivitis, rhinorrhea
Maculopapular rash appears after the prodrome and coincides with what?
strong cell mediated immune response and clearance.
Measles case definition
child comes in with a generalized rash lastingmore than 3 days, temperature of 101 (38.3), cough, rhinorrhea, conjunctivitis
If these symptoms are reported and linked to another case with similar symptoms
the case should be reported to the state and local health department and MMWR
Initial sites of measles infection
tracheal and bronchial epithelia
After infecting the tracheal and bronchial epithelia, where does the virus spread
lymph nodes, replicates in lymph nodes and forms syncytia. This eventually leads to viremia where the virus gets into monocytes
What is significant about measles infecting monocytes
These are the precursors to immune cells like T cells, hurts the immune response pretty severely
Where does measles rash start?
back of the neck and forehead
What the hell are Koplik spots
Occur right before the rash appears. red spots with blue/white centers on the inside of the upper lip and cheek
Measles complications?
Immune suppresion, suppression of delyed type hypersensitivity like TB TEST
- Acute disseminated encephalomyelitis (ADEM) or
Post infectious encephalomyelitis (PIE)
This is an autoimmune demyelineting disease that results in convulsions, deafness, retardation
-Measles Inclusion body encephalitis
-Subacute sclerosing pancephalitis
What kind of vaccine is the measles vaccine
Live attenuated
What is the basis for the vaccines success
Measles Mumps and RUbella are antigenically stable viruses. They don’t change
First dose of MEasle at 12-15 mths, 2nd at 4-6 years
truth
Measles virus is a phenomenal candidate for immunization. Why
There is only one serotype, cases are easily identifiable so those infected can be quarantined, there is no animal reservoir
Mumps colonizes where?
mucosal epithelium of the nasopharynx and upper respiratory tract. Replicates in URT then spreads to lymph nodes. Not as contagious as measles
First clinical sign of mumps
swelling of parotid…big fat face
Mumps cause a rash>
NOPE. No rash
Approximately half of mumps has some CNS involvement like?
Meningitis, usually not very serious
Some had infection of the cochlea which led to deafness
What is the major complication seen in post pubertal men with mumps
Testicular swelling
Rubella structure
enveloped, pos sense RNA virus
Rubella causes
mild disease, sore throat, conjunctivitis,
Measles like rash, starts on the face and spreads to extremities
The real issues with rubella
can cause birth defects in infected mothers, virus spreads to the fetus and infects all organs pretty much
Highest risk of rubella causeing birth defects
second and third trimesters
Contraindications for the measles vaccination
anyone who has had a life-threatening allergic reaction to gelatin or neomycin
people who are moderately or severely ill at the time of vaccnation
Pregnant women should wait
women should not get pregnant for 4 weeks after the MMR vaccine
ANyone who is immunosuppressed