picornavirus = “little RNA virus” (picoRNAvirus)
• | this family of viruses have similar structure and replication |
• | there are two genera: enterovirus and rhinovirus |
enterovirus:
• | infect intestinal epithelial and lymphoid (tonsils, Peyer’s patches) cells |
• | spread by fecal-oral route |
• | hepatitis A virus, poliovirus, Coxsackie A, B, and echovirus |
Hand, Foot and Mouth disease:
• | pathogen = coxsackie A16 |
• | mild symptoms of low grade fever, sore-throat |
• | enanthem: 90%; apthae-like erosions, small and asymptomatic |
• | cutaneous lesions: 2/3 of patients… |
• | within 24 hours of enanthem |
• | red macules that rapidly become pale, white, oval to cigar-shaped vesicles with a red areola |
• | hands and feet, especially palms and soles |
• | heal in 7 days without crusting or scarring |
• | culture virus from stool; acute and convalescent serum titers |
• | histology: reticular degeneration (multilocular blisters vs. herpes virus) |
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