Transfusion transmitted diseases.

Transfusion transmitted disease (TTD) is a major challenge to the transfusion services all over the world. The problem of TTD is directly proportionate to the prevalence of the infection in the blood donor community. In India, hepatitis B/C, HIV, malaria, syphilis, cytomegalo virus, parvo-virus B-19 and bacterial infections are important causes of concern. Hepatitis B and C infections are prevalent in India and carrier rate is about 1-5% and 1%, respectively. Post transfusion hepatitis B/C is a major problem in India (about 10%) because of low viraemia and mutant strain undetectable by routine ELISA. HIV prevalence among blood donors is different in various parts of the country. It may not be so alarming as projected by some agencies. In one study from north India, confirmed HIV positivity was found in 0.2/1000 blood donor. Post transfusion CMV is difficult to prevent but use of leukocyte filters may help to reduce it significantly. Parvo virus B-19 infection in blood donors is 39.9% which may increase morbidity in multitransfused or immunocompromised patients. Current symphilis tests may not be sensitive but it should be continued to exclude high-risk donors. Malaria is a real problem for India due to the lack of a simple and sensitive screening test. Incidence of bacterial contamination is greatly reduced due to improved collection/preservation techniques and use of antibiotics in patients. However, proper vigilance and quality control is needed to prevent this problem. Total dependence of altruistic repeat voluntary donors and use of sensitive laboratory tests may help Indian blood transfusion services to reduce incidences of TTDs.

Survey of parvovirus B19 infection in a cohort of pregnant women in Belém, Brazil

A total of 300 pregnant women were screened for the presence of human parvovirus B19 IgG and IgM antibodies by an enzyme-linked immunosorbent assay (ELISA). Overall, 253 (84.3 percent) were found to be IgG-positive and IgM-negative (IgG+IgM-), 42 (14 percent) had neither IgG nor IgM antibodies (IgG-/IgM-) and 5 (1.7 percent) were both IgM- and IgG-positive (IgG+/IgM+). Maternal serology was performed routinely for cytomegalovirus, rubella, toxoplasmosis and syphilis. All IgG-/IgM- and IgG+/IgM+ women were followed until the time delivery, with venous blood samples taken monthly from each, one IgG-/IgM- mother seroconverted to IgG+/IgM- and B19 DNA was detected by nested polymerase chain reaction technique (PCR) in her serum. All babies born to IgG+/IgM+ mothers (and from the one who seroconverted) were IgG+IgM-, but no B19 DNA could be detected in their sera and no adverse effects were documented either by ultrasonographic examination or by detection of maternal serum alpha-fetoprotein. While 5 of the mothers delivered normal children at term, one gave birth to a premature (low-weight) baby who developed severe anemia and had convulsions. However, this mother was found to have toxoplasma-specif IgM. Our data indicate a low frequency of B19 infection in pregnancy in our region, at least during interepidemic periods. This appears to be partly due to high prevalence of prior infection among pregnant women. Recent B19 infection in 6 women did not lead to adverse fetal outcomes. This observation, however, in a small number of serologically positive patients, does not contradict the observations by others that recent infection does converg a risk for the fetus.

Infecçäo pelo parvovírus e gestaçäo / Parvovirus infection and pregnancy

As doenças virais, especialmente rubéola, citomegalovírus, varíola e herpes simplex, säo causas bem estabalecidas de infecçäo intra-uterina levando a morte fetal, doença neonatal severa ou anomalia congênita. Recentemente, muitos trabalhos têm implicado um vírus relativamente recém-descoberto, o parvovírus B19, como causa de infecçäo intra-uterina, hidropisia fetal e morte fetal após infecçäo aguda na grávida. O presente trabalho objetiva fornecer informações relevantes sobre a epidemiologia, patogenia e quadro clínico da infecçäo, bem como a conduta obstétrica pertinente

Infecciones por Parvovirus en humanos / Infection by human Parvovirus

El Parvovirus humano (PVH), como otros Parvovirus, es capaz de replicarse autónomamente, mide 23mm y tiene ácido deoxiribonucléico de cadena sencilla como material genético. La infección en humanos da lugar a un cuadro viral no específico durante el prodromo seguido por viremia. Esta puede dar lugar a diferentes tipos de erupciones (incluyendo el síndrome de eritema infeccioso) y/o artropatías. También se le ha asociado a un aumento en abortos espontáneos en mujeres embarazadas con infección aguda y es la causa de las crisis aplásticas en pacientes con anemias hemolíticas. Múltiples Parvovirus serológicamente diferentes al PVH se encuentran en las heces fecales y son la causa principal de la gastroenteritis infecciosa aguda no bacteriana en personas mayores de cinco años de edad