Measles, Mumps, Rubella, Parvovirus B19 Flashcards
Measles:
- what causes it ?
- describe the virology?
- epi / transmission
Paramyxovirus Mirbilivurs
Enveloped, non segmented SS RNA Virus
helical
1 serotype
HIghly contagious; airborne transmission;
Meales:
- Pathophysiology
- clinical manifestaions / course
- complications
Invasion of Respiratory epithelium
travels to LNs
Viremia
Transient but profround immunosuppression
Clinical Presention:
1st) Fever + 3 Cs (Conjunctivitis, cough, coryza)
2nd) K - Koplick spots (enanthem)
3rd) Rash (Exanthem) head to toe
Complications: overwhelming secondary infeciton; encephalitis
Meales
- diagnosis
- prevention
- treatment
Dx: Acute and Convalescent Igs (4 fold rise in IgGs), RT PCR
Prevention: Vaccine to the single Meales serotype
Treatment: none – Treat secondary bacterial infections; give vitamin A
Mumps
- what causes it ?
- describe the virology
- epi / transmission
Paramyxovirus
Virology: enveloped, SS RNA, non segmented
helical
single serotype
Transmission: saliva and respiratory droplets
Mumps:
pathophysiology
Clinical features
complications
- Infection begins in upper resp tract
- LNs – > viremia –> infects salivary glands and other glandular tissue
Clinical: 1/3 asymptomatic
affects:
- Salivary glands (parotitis)
- Testes (orchitis)
- Pancrease
rare complications: Encephalitis, deafness, infertility
Mumps:
Dx
Treatment
Prevention
Dx: Acute and convalescent titers
Treatment: ?
Prevention: Live attenuated vaccine as part of MMRV (v=varicella)
Rubella
- what bug
- describe the virology
- epidemiology/transmission
Togavirida
Enveloped Icosahedral, ss RNA
highly contagious
Respiratory droplets
Rubella
- pathogenesis
- clinical features
- complications
Pathogenesis:
- infects upper resp tract
- local LNs
Clinical Features: - usually asymptomatic - Malaise, Cervical LAD, arthritis - Rash -- Develops head to toe; disapperas head to toe Overall mild infection
cell mediated immunity eliminates the infection
Rubella
- what is congential rubella syndrome?
- what is the triad of symptoms
Why is it important that we vaccinate for this ?
If women contract rubella during their pregnancy, can pass to children. Worse if during first trimester
Triad of disease: carardacs, deafness, heart disease (patent ductus arteriosis, pulmonary artery stenosis)
Other: HSM, growth and mental retardation;
Extramedullary hematopoesis (“blueberry muffin rash”
Erythema Infectiosum
- what is the bug?
- describe the virology
- what are the only cells it infects?
- epi/transmission
- Parvovirus B19
- Small, Naked Capsid
- SS DNA
- only infects Mitotically active cells (such as erythroid precursors of the bone marrow)
- Epi: Very common; 65% of adults infected by age 40
transmit: respiratory secretions; vertically;
Erythema Infectiosum (Parvovirus)
- pathogenesis
- classic Clinical manifestations
- complications
Path: - Replicates in the resp tract; viremia; moves to bone marrow where it is cytotoxic; leads to anemia
Clinical:
75% asymptomatic
- Slapped Cheek Rash
- followed by diffuse lacey reticular rash
- Once rash appears, no longer infectious
-other manifestations: -
Arthralgias
Anemia (aplasia crisis in sick cell patients)
-chronic B19 anemia in immunocompromised pts
- Congenital: Non Immune Hydrops fetalis
- myocarditis
Erythema Infectiosum (Parvovirus)
- Dx
- Mangement of anemia, chronic infection, exposed pregnant women
Dx: Clinical Presenations
Acute and convalescent antibodies
PCR
Mangement:
Aplasitc Crisis and severe anemia – transfusions
Chronic Immunodeficient Infection – Passive IGs
Exposed Pregnant women – explain low risk; offer diagnostic venous sampling
what are the classic childhood exanthems ?
First – Measles
Second – Scarlet fever Group A Streptococcus
Third - Rubella
Fourth – ?
Fifth –Erythema infectiosum Parvovirus B19
Sixth –Roseola infantum HHV-6
