Advances in Human B19 Erythrovirus Biology

Abstract

Since its discovery, human parvovirus B19 (B19V), now termed erythrovirus, has been associated with many clinical situations (neurological and myocardium infections, persistent B19V DNAemia) in addition to the prototype clinical manifestations, i.e., erythema infectiosum and erythroblastopenia crisis. In 2002, the use of new molecular tools led to the characterization of three different genotypes of human B19 erythrovirus. Although the genomic organization is conserved, the geographic distribution of the different genotypes varies worldwide, and the nucleotidic divergences can impact the molecular diagnosis of B19 virus infection. The cell cycle of the virus remains partially unresolved; however, recent studies have shed light on the mechanism of cell entry and the interactions of B19V proteins with apoptosis pathways.Before the recent descriptions of human bocavirus (2) and human parvovirus 4 (PARV4) (41), parvovirus B19 ([B19V] or erythrovirus B19) was the only known member of the Parvoviridae family to infect humans. The Erythrovirus genus contains B19V, erythroviruses that infect several simian species, and the parvovirus from Manchurian chipmunks (87a). These viruses share the remarkable property of replicating in and destroying erythroid progenitors. This strong in vitro tropism explains the difficulties in studying the replicative cycle of these viruses; indeed, the in vitro production and culture of erythroid progenitor cells remain delicate. An infectious B19V clone was described only recently (102), and its use, although mostly limited and allowing only a small amount of progeny production, led to constructions of recombinant viruses that were helpful in understanding the steps of the virus life cycle and the toxicity of the virus. Discovered in 1975 (19), B19V can cause a wide range of mild and self-limiting clinical manifestations, such as erythema infectiosum (fifth disease) and oligoarthritis (98). B19V infection can also cause acute anemia by aplastic crisis in patients whose red blood cells have shortened survival times (i.e., patients with sickle cell disease, thalassemia, spherocytosis, or any disorder of hemoglobin gene expression or red cell membrane constitution), chronic anemia in patients with congenital immunodeficiencies or human immunodeficiency virus (HIV) infection or who are undergoing chemotherapy for malignancies or organ transplants (48, 58), and hydrops fetalis or intrauterine death in infected fetuses (86). Recently, cases of neurological manifestations have been associated with B19V infection (22), as have myocardium infections (4,5,47,83), and the spectrum of B19V-linked diseases may further increase. CLINICAL MANIFESTATIONSThe primary route of transmission of B19V is the respiratory tract (via aerosol droplets), with a majority of infections occurring during childhood, but the infection may also be transmitted by organ transplantation and especially by transfusion of blood components, in particular by packed red cells from blood collected during the short preseroconversion vi...

Genotype 1 of human parvovirus B19 in clinical cases

“…Genotype 2 appears to be restricted to people born before 1970, and genotype 3 predominantly occurs in people from West Africa, France and Brazil. 17 Some studies have shown that B19V genetic diversity may depend on the geographical location and the year of isolation in patients. In this study, all isolates belonged to genotype 1.…”

“…In this study, all isolates belonged to genotype 1. 17 In Brazil, all three genotypes have been identified, although genotype 1 is the most common.…”

Chronic Fatigue Syndrome and Viral Infections

“…Although it is frequently detected by PCR in the nasopharynx of viremic patients with primary lower respiratory tract infections, other co-infecting respiratory viruses are frequently detected (Servant et al, 2010). As far we know, only parvovirus B19 is involved in CFS.…”

“…Discovered in 1975 (Cossart et al,1975), B19 can cause a wide range of mild and selflimiting clinical signs, such as erythema infectiosum (fifth disease) and oligoarthritis (Servant et al, 2010). B19V infection may also cause acute anemia due to aplastic crisis in patients with shortened red cell survival and the chronic anemia of immunocompromised patients, i.e.…”

The effects of Parvovirus B19 infection on pregnant women and fetus

“…Arthropathy is common in infected patients, especially in women. B19 infections may cause transient aplastic crisis in patients with hematological disease, chronic anemia in immunocompromised patients, and fetal hydrops and fetal death in the fetus, although infections in immunocompetent patients are generally mild or subclinical (1)(2)(3)(4). Fetus may be infected during maternal asymptomatic or symptomatic B19 infection.…”