L78 Flashcards
What is exanthem?
Rash on skin
Vs. enanthem = rash on mucous membrane
Big 5 childhood diseases that cause rash
Measles Strep pyogenes Rubella Parvo - erythema infectiosum Roseola (HHV 6)
Symptoms of measles
3 Cs + K Conjunctivitis Cough Coryza = running nose Koplic spots = enanthem rash in the mouth w/ grey middle
Describe the measles rash: appearance, timing
= Rubeola Develops after Koplic spots Starts on face Progresses centrally Moves to periphery & toes
Geographic tip offs for measles
California
Switzerland
Measles incubation
1 up to 2 wks
Day 10 - fever
Day 14 - rash
Infectious before symptoms start during this incubation period
Measles transmission
Air-born
Kids in school
Diagnose measles
- Clinical
2. Serum testing - IgM/G - watch out for false +/-
What tissue does measles infect?
Respiratory epithelium –> LN
Which immune system is important for measles resolution?
Cellular
Measles genome
(-) ssRNA
Enveloped
Labile
What cell types does measles infect during primary viremia?
T cells! Same time once penetrated resp epi
Causes temp immune suppression that is definitely noticeable
- Pna
What CNS disease might result from measles? When might this present?
Encephalitis
Acute or sub-acute years later!
What nutrition deficiency would make measles worse?
Vit A def
When do you give the measles vaccine?
9mo-1 year
Live, attenuated vaccine - therefore babies who have mom’s Abs might not have right response
Mumps symptoms
Swollen neck!!
Parotid gland
1 sided - may spread bilateral
Mumps genome
(-) ss RNA Capsid w/ - Hemagglutinin (H) - Neuraminidase (N) - Fusion protein (F) Lipid bilayer from host cells
Mumps pathogenesis - where does infection start and move
Start @ URT epi
to LN
Viremia -> glandular tissue (scrotum)
Which branch of immunity controls mumps infection?
Cellular
Mumps transmission
Resp drops
Saliva
Fomites
Mumps incubation
2-3 wks
Longer than measles
When is mumps contagious?
2 days before jaw swelling –> 5 days after
Which CNS disease is associated with mumps?
Aseptic meningitis
Mumps complications
Encephalitis
Deafness
Infertility
Mumps vaccine. Who don’t you give this to?
Live, attenuated
As MMR/V
DONT give to PREGNANT
Rubella symptoms
Head –> toes : disappears as it progresses
- Correlates w/ appearance of Abs
Cervical swollen LN
Arthritis - esp adults
Rubella genome
+ ssRNA
Rubella pathogenesis
URT epi
LNs
Viremia
What is the role of Abs vs cell immunity for rubella?
Ab: limit spread
Cell: elim infection
Rubella incubation & infectious period
2-3 wk incubation
Infectious: prodome –> 2 wks post rash
What is congenital rubella syndrome?
In BABIES :( Cataracts Heart disease Deafness "Blue berry muffin rash"
Why do we vaccinate vs rubella?
To cover women who might become pregnant to prevent congenital rubella syndrome
Parvovirus symptoms - correlation to infectiousness
- Fever due to viremia = infectious
2. Slap check rash = erythema infectiousum
Parvovirus genome
ss DNA
What cells does parvo replicate in?
Erythroid precursors
Fetal capillary endothelium in placenta
Parvo patho
Replicates @ RT
Viremia –> bone marrow
Secondary diseases that might result from parvo
Arthritis
Anemia - duh, infecting blood precursors!
Non-immune fetal hydrops !!
Myocarditis
