There is no evidence of specific congenital malformations due to in utero exposure to HPV B19. Associations of HPV B19 infection include encephalitis, neuropathies, myocarditis, nephritis, SLE, HSP and rheumatoid arthritis. The exact role of HPV B19, if any, in these diseases is unclear. Peak incidence occurs in winter and early spring. Community epidemics usually last 3-6 mo.
Subclinical infections are common.
Infants and adults are affected infrequently. Erythema infectiosum is usually a biphasic illness. The above symptoms precede an approximately 7 d, symptom-free period, followed by a typical exanthem that occurs in 3 phases. Initially, a bright red, raised slapped-cheek rash with circumoral pallor develops. The nasolabial folds are usually spared.