Males and females are equally infected. Arthropathy is more common in women. Women may be affected by complications in pregnancy. Parvovirus B19 infection can lead to the classic symptoms of erythema infectiosum in adults, but more often will manifest as an acute arthropathy without the cutaneous eruption. Erythema infectiosum typically has an incubation period of 4-14 days and is spread primarily via aerosolized respiratory droplets.
Transmission also occurs through blood products and from mother to fetus.
The prodromal phase is often so mild that it is rarely noticed but may include headache, coryza, low-grade fever, pharyngitis and malaise. Infrequently nausea, diarrhea, arthralgias and abdominal pain may occur. In immunocompetent hosts, the patient is viremic and capable of spreading the infection only during the incubation period. The classic cutaneous findings follow within 3-7 days for some patients, while others may have none. Pertinent physical findings are predominantly limited to the skin and joints.