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Measles (Rubeola) Virus
Paramyxoviridaegenus Morbillivirus
Enveloped single-strandedRNA virus
Reservoir Host: HumanRelated Viruses
Canine distemperRinderpestPeste des petits ruminantsPhocine distemperDolphin distemperPorpoise distemper
Phylogeny of Known Morbilliviruses
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Measles Virus Genetic Variants
Measles Virus Genetic Groups
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Measles Epidemiology
Measles EpidemiologyResurgence Associated with Group 2 Virus
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Human Measles CasesVaccination Status
Measles (Rubeola) Virus InfectionTransmission: Aerosol droplet; direct contact with
nasal or throat secretions, fomitesHighly infectious virus
Disease: Similar in humans and nonhuman primatesMost species of primates are susceptibleIncubation period 7-14 daysInfectious period 1-2 days prior to onset of prodrometo ~ 4 days after appearance of rashSubclinical infections have been documented
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Measles VirusZoonotic Transmission
Measles Virus Infection
Clinical Measles Prodrome: 7-14 days after infection
Lasts 2-3 daysFever, malaise, anorexia, coryza, cough, conjunctivitis, Koplik spots
Rash: 3-7 days post onsetMaculopapular eruptionStarts on head/face – spread to trunk/limbs
becoming generalizedPersists 3-4 days
Leukopenia - common
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Measles Virus Pathogenesis
Measles Virus InfectionComplications and Sequelae
ComplicationsPrimary viral or secondary bacterial
Otitis mediaPneumoniaEncephalitisEnteritis
SequelaeSubacute Sclerosing Panencephalomyelitis (SSPE)
(Reactivation of latent MV?)
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Primary measles interstitial pneumonia and hemorrhage
Coalescing rash and inguinal lymphadenopathy
“Morbilliform” maculopapularrash in human and rhesusmacaque
Measles Virus Infection
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Measles Virus InfectionAtypical Koplik’s Spots in NHP
Koplik’s spots – pale areas of focal necrosis usually found in buccal mucosal epithelium
Measles Virus InfectionPathologic Features
Broad Tissue Tropism
Intranuclear inclusions
Formation of multinucleated “giant cells” (Syncytia)
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Measles Virus Immune Suppression
Impaired cellular immune function
Impaired humoral immune function
CNPRC Measles Outbreak, 1987
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Human Measles CasesCNPRC Measles Outbreak 1987
Employee; animal contact3-22-8722F5
Employee; animal contact3-7-8721F4
Employee; animal contact2-25-8727F3
Household contact case 12-8-8730M2
Employee; animal contact1-28-8728F1
ExposureOnsetAgeSexCase #
CNPRC Measles Outbreak 1987Epidemiologic Evidence of Monkey-to-Human Transmission
Case 3Exposed to confirmed monkey measles on 2/16/87Onset of measles on 2/25/87 (9 days)No known exposure to human cases (CNPRC or community). Worked only weekends
Case 4Exposed to confirmed monkey measles on 2/24/87Onset of measles on 3/7/87 (11 days)No known exposure to human case 3 or other human cases
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Measles Virus InfectionAbortions/Stillbirths Outdoor-housed Macaques
CNPRC 1984-1987
45.8551201986-87*
18.1311711985-86
21.6301691984-85
%Stillbirths/AbortionsPregnanciesBirth Year
*Measles outbreak
Measles Virus InfectionNeonatal* Mortality in Macaques
CNPRC 1984-1987
35.42365Outdoor
3.5385Indoor1986-87#
5.78140Outdoor
2.3143Indoor1985-86
5.07139Outdoor
0034Indoor1984-85
%Neonatal DeathsLive BirthsHousingBirth Season**
*Neonate = < 28 days of age** Through April of each year# Measles outbreak
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Measles Virus InfectionWild Nonhuman Primates
Measles virus antibodies found in wild NHP populations having human contact (low prevalence)
Possible introduction of measles into habituated troop of Mountain Gorillas 1988, 1990
Measles Virus InfectionTreatment and Prevention
No specific treatmentSupportive carePrevention of secondary bacterial infections
Natural infection confers life-long immunityVaccine preventable disease
Attenuated live MV vaccine (Attenuvax)Canine distemper-measles vaccine provides
protection against MV challenge in NHP*Attenuated live MV vaccine may be pathogenic
in New World monkeys
* Christe KL, et al. Comp Med 52:467-472; 2002;
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