• "Human Parvovirus B19" causes this benign rash disease, which is more common in school-age children. The infection spreads through droplets.
• In the viremia phase, which lasts 7-10 days, nonspecific, flu-like symptoms are seen.
• The characteristic rash appears on the 10th-14th days.
• Before the rash, the patient is in the viremia phase and is highly contagious. Contagion disappears from the onset of the rash.
• There is no enanthemia (rash in the mouth).
Clinic
• Children aged 5-15 years constitute 70% of the cases.
• In about half of the cases, the infection is subclinical. At the beginning of the disease, symptoms such as fever (38-38.5 °C), weakness, loss of appetite, sore throat are observed and these symptoms continue for 2-3 days (prodromal phase). Then the rash appears.
• The first sign of the disease is a typical rash. The rash appears in 3 phases.
Phase 1
• The rash that starts on the cheeks coalesces, causing the characteristic slapped face appearance. No rash is seen in the peroral area.
Phase 2
• Within 1-2 days, the rash begins to spread symmetrically towards the extensor surfaces of the trunk and extremities. There is no rash on the palms and soles of the feet. Conjoined lesions begin to heal in their midsection, causing a "lace appearance".
Phase 3
• The rash begins to fade from the central areas and the typical reticular rash occurs. The rash heals in 4-5 days without desquamation. But in some patients it may take 1-3 weeks. It may be itchy.
• Glove-sock-like purpuric rash may be seen on the hands and feet.
Laboratory Findings
• Parvovirus 819 is not detectable in routine viral cultures.
• IgM and IgG antibodies should be checked for diagnosis.
Complications
• Arthritis: It is the most common complication. It is seen in older patients. There is symmetrical pain and stiffness in the peripheral joints. It occurs following the rash and persists for 2-4 weeks. It leaves no sequelae.
• Aplastic crises: Parvovirus B19 replicates primarily in erythroid progenitor cells. Therefore, reticulocytopenia occurs at the 1st week of illness. While this event goes unnoticed in normal people, it causes severe anemia in cases with chronic hemolytic anemia. In some cases, pure erythrocytic aplasia, chronic pancytopenia, idiopathic thrombocytopenic purpura and hemophagocytic syndrome have been described due to Parvovirus B19 infection.
• Intrauterine infections: Parvovirus B19 may cause fetal infection in susceptible pregnant women and may cause hydrops fetalis. It is the most common infectious cause of non-immune hydrops fetalis. Fetal death is seen in 6% of cases. It also causes myocarditis, CHF, heart blocks and anemia.
• Parvovirus B19 does not cause congenital anomalies.