Paramyx 2 and Toga Flashcards
Morbillivirus is in what family of virus?
Paramyxo
Morbillivirus causes what named disease?
Measles (Rubeola)
Morbillivirus hosts
Only humans
Morbillivirus genome and shape:
ss -RNA , helical
Envelope proteins of Morbillivirus
HA + Fusion (F)
How many subtypes of Morbillivirus are there? What does this mean regarding vaccinations/immunity?
One antigenic type…. This makes vax easy, and immunity permanent.
Morbillivirus lacks what envelope protein?
Neuraminidase
Morbillivirus : Viremia Y/N?
Yes, acute manifestations in lymph and resp.
Morbillivirus clinical characterization (two stages)
URT symptoms during Prodromal stage…… Maculopapular rash during eruptive stage.
Morbillivirus three C’s during what stage?
Prodromal stage: Coryza, Cough, Conjunctivitis
Major Sign for Morbillivirus
Koplik spots (second molar oral mucosa)
Morbillivirus Rash pattern
Head 1st, Limbs 2nd…………Erythematous-> Confluent……..rash fades in the same sequence it appears
Koplik spots appear after _____ days
2-3
Morbillivirus fever y/n?
yes. 104
Atypical Morbillivirus forms in whom?
Patients with incomplete immunity d/t vaccination with the original killed-virus vaccine
Modified Morbillivirus severity?
Less severe. Exposed people given serum IG
Morbillivirus common complications:
Otitis Media, PMA, Croup (laryngotracheobronchitis), Exacerbation of TB…..(KERATITIS that can lead to blindness)
_____ was one of the main reasons for introducing Morbillivirus vaccination?
Encephalitis
2 Major rare complications of Morbillivirus
Encephalitis and SSPE (subacute sclerosing panencephalitis)
SSPE caused by _____ Morbillivirus
immune resistant
SSPE tends to occur…
YEARS after measles… incubation of 10.8 years
Other rare complications of Morbillivirus
a bunch of -itis’s………..myocard/pericard, hep, append, ileocol.
Pregnancy complications of Morbillivirus
Pneumonitis, SSPE, hepatitis, but LOW PERINATAL transmission rates
Morbillivirus infectious time period?
4 days before and after RASH onset
_____ is key to Morbillivirus pathogenesis
Viremia
Viremia (s) locations
1- reticuloendothelial system……..2- epithelial surface (conj, UT, CNS)
Morbillivirus first replicates in…
the RESP Tract and LYMPH nodes
Second Morbillivirus viremia does what?
disseminates virus to other systems after 5-7 days
Morbillivirus causes generalized _____
immunosuppression
Morbillivirus causes _____________________ with immunodeficient patients
fatal GIANT cell PNA
___ and ___ are most common complications of Morbillivirus
Ear infections and PNA
1 in 4 people in developing world die from _________ related to Morbillivirus.
malnutrition and Vit A deficiency. Leading cause of BLINDNESS in African children.
Morbillivirus Transmission
Airborne (respiratory)
Antibodies to Morbillivirus first appear when?
2 days after rash develops
Morbillivirus clinical diagnosis chiefly made from
Triad, Koplik spots, adn Cephalocaudal rash
Lab tests for Morbillivirus
CBC (leukopenia), LFT (TA levels high), IgG and IgM testing, RTPCR
Morbillivirus vaccine type
live attenuated MMR
Rubulavirus a.k.a
Mumps
Mumps genome
ss -RNA
Mumps host
humans only
Mumps serotypes
only one serotype – lifelong immunity
Mumps incubation time
12-26 days
Mumps Major Sx
Swelling, FEVER, Jaw/neck pain, Fatigue
up to ___% of Mumps are asymptomatic
20%
Major mumps complications
Orchitis/Oophoritis
Orchitis is uncommon in…
boys under 10 years old
Oophoritis occurs in ___% of postpubertal females
7%
Orchitis occurs in up to ___% of postpubertal males
50%
Other Mumps complications (not orchitis/oophoritis)
Pancreatitis, Aseptic Meningitis, Encephalitis (w permanent CNS problems)
Most specific indicator of pancreas involvement in Mumps is _______
Lipase levels
Mumps locally replicates in ______
Nasopharynx and regional lymph nodes
Mumps viremia established after how long?
12-25 days
Mumps virus disseminates from upper airway during ______
Viremia
Mumps viremia leads to ______ infection
systemic
Mumps transmission
Person to person, respiratory droplets, fomites
Mumps season
Late winter-spring
Mumps infectious period
3 days before, 9 days after onset
Mumps treatment
none
Mumps vaccine schedule
First dose as MMR @ 12 months or olde…….. Second dose for school-aged kids or high exposure individuals
Togaviridae includes what viruses?
Rubella + Alphavirus
Rubella genome:
ss+RNA
Rubella shape
icosahedral
Rubella enveloped y/n?
yes
Rubella serotypes/variants?
only one
Rubella replication pattern
+RNA acts like mRNA and binds to ribosome. Translated to EARLY and LATE phases.
2/3 of Rubella genome translates….
one polypeptide that is cleaved into (NSP1-4) protease and RNA dependent RNApol
1/3 of Rubella genome translates…
Capsid and Envelope (E1-3) proteins
Rubella is aka
German Measles
Rubella is generally a _____ disease
mild
Serious version of Rubella is…
Congenital Rubella Syndrome - causes fetal death or defects
A Rubella infection may be transmitted from a ________ person
completely asymptomatic
Rubella incubation time
2-3 weeks
___ occurs in 50-80% of Rubella cases
Rash
Rubella’s most characteristic clinical feature:
Swollen lymph glands behind the ears
Infected adults can develop ____ from Rubella
Arthritis
Conginital Rubella Syndrome … ___ chance of passing on to fetus if infected early in pregnancy?
90%
Three conditions mentioned as being related to Congenital Rubella Syndrome
Autism, DM, Thyroid dysfunction
Rubella isn’t really as much of a concern for…
males (because congenital is the bad one… only women can pass that one)
Three most common conditions caused by Congenital Rubella?
Hearing Loss, Patent Ductus Arteriosus, Cataract
Rubella, unlike other Togaviruses, is a ________
Respiratory virus
Rubella hosts
Humans only
Rubella spreads from nasopharynx to ____ & ____, which causes _____
Lymph nodes + Macrophage/Monocyte system……. causes viremia
Circulating Rubella antibody can block what
Primary and Secondary viremias, as well as vertical transmission through the placenta…. therefore IMMUNE DEFICIENT women can pass to fetus.
Rubella Dx Tests
IgG titre, Presence of Rubella specific IgM + rash = confirm diagnosis
Rubella vaccine
- MMR 2. Tetravalent MMRV
_____ Rubella vaccine no longer available in US
Monovalent
MMR is given in…
two doses