chickenpox + MMR Flashcards
chickenpox causative organism
primary infection of varicella zoster virus
- shingles is a reactivation of the dormant virus in dorsal root ganglion
chickenpox spread + incubation period
spread via respiratory route
10-21days
can be caught from someone with shingles
infective period in chickenpox
4 days before rash, until 5 days after rash first appeared
NICE - advise most infectious is 1-2days before rash appears but infectivity continues until all lesions are dry + have crusted over (about 5 days)
chickenpox presentation
fever initially
itchy rash starting on head/trunk before spreading
initially macular -> papular -> vasicular
management of chickenpox
keep cool, trim nails
calamine lotion
advise around infectious period
secondary bacterial infection causative organisms in chickenpox
most commonly - small area of cellulitis
sometimes - necrotising fasciitis due to invasive group A strep
NSAIDs increase this risk
complications of chickenpox
pneuomonia
encephalitis (cerebellar involvement may be seen)
disseminated haemorrhagic chicken pox
rare - arthritis, nephritis, pancreatitis
measles
uncommon (in developed) due to vaccine
one of most infectious known viruses
RNA paramyxovirus
measles incubation
10-14days
infective from prodrome until 4 days after rash starts
measles features
prodromal phase - irritable, conjunctivitis, fever
Koplik spots
- develop before rash
- white spots (“grain of salt”) in mouth
rash
- starts behind ear then whole body
- discrete maculopapular rash becomes blotchy + confluent
- desquamation sparing palms+soles may occur after a week
measles investigations
IgM antibodies can be deteted within a few days of rash onset
maangement of measles
mainly supportive
- admit if immunosup or pregnant
notifiable disease - inform public health
measles complications
commonest = otitis media
- pneumonia = commonest cause of death
- encephalitis - 1-2wks after onset
- subacute sclerosing panencephalitis - 5-10yrs following illness
management of contacts with measles
if not immunised, MMR should be offered –> give within 72hrs
mumps features
RNA paramyxovirus
- fever
- malaise, muscular pain
- parotitis (earache, pain on eating) - unilateral initially then bilateral in 70%
mumps spread + incubation period
by droplets
- infective 7days before + 9 days after parotid swelling starts
incubation period = 14-21days
management of mumps
rest
paracetamol for high fever/discomfort
notifiable disease
mumps complications
orchitis - 4 or 5 days after
(not in pre-pubertal obvs)
hearing loss - transient, unilateral
meningoencephalitis
pancreatitis
Rubella
viral infection caused by togavirus
- rare due to MMR
incubation = 14-21days
infectious from 7days before sx to 4 days after onset of rash
rubella presentation
prodrome - low-grade fever
rash
- maculopapular
- initially on face before whole body
- fades by 3-5day
lymphadenopathy - suboccipital + postauricular
rubella complications
arthritis
thrombocytopenia
encephalitis
myocarditis
