No abstract

Attachment to carbohydrates of the histo-blood group type of several human Rotavirus strains (RVA) has recently been described. Synthesis of these ligands requires a functional FUT2 enzyme, suggesting that FUT2 null homozygote (ie, nonsecretor) individuals may not be recognized by most human RVA strains. Whereas such individuals represent 20% of the control population, this retrospective study determined that none of 51 patients infected by P[8] rotavirus strains were nonsecretors. The lack of α1,2fucosylated carbohydrate motifs in the gut surface mucosa is thus associated with resistance to symptomatic infection and virus attachment to such motifs is essential to the infection process.

To determine the incidence and clinical relevance of active human herpesvirus 6 (HHV-6) infection, 92 consecutive unselected recipients of autologous or allogeneic stem cell grafts were investigated in a prospective longitudinal study. Active infection was assessed by the presence of viral deoxyribonucleic acid (DNA) in 846 peripheral blood mononuclear cell specimens and 115 plasma specimens, by means of a specially developed polymerase chain reaction designed to avoid detection of latent genome. The incidence of HHV-6 infection observed was 42.5%, irrespective of the type or source of graft, and infection was significantly associated with partial (P=.002) or total myelosuppression (P=.01) and fever (P<. 000001). Infusion of bone marrow as the source of graft, reactivation occurring before platelet or neutrophil engraftment, and presence of HHV-6 DNA in plasma were identified as risk factors for symptomatic HHV-6 infection (P<.002).

Microsporidiosis cases due to Enterocytozoon bieneusi and Encephalitozoon intestinalis are emerging opportunistic infections associated with a wide range of clinical syndromes in humans. The aim of this study was to specify microsporidial epidemiology in two different geographical areas. From November 2004 to August 2005, 228 and 42 stool samples were collected in Niamey, Niger, and Hanoi, Vietnam, respectively. Screening for microsporidia was performed using UV-light microscopy. Detection was confirmed by molecular biology using two methods specific for E. bieneusi and E. intestinalis. All samples positive for E. bieneusi were subjected to genotyping. In this study, we found high prevalences of microsporidiosis among human immunodeficiency virus-infected patients, 10.5% and 9.5%, respectively, in Niamey and Hanoi. These levels of prevalence are similar to those recorded in European countries before highly active antiretroviral therapy was introduced. In the samples positive for E. bieneusi, we found seven distinct genotypes, including two genotypes not previously described. The E. bieneusi genotype distributions in the two geographical areas suggest different routes of infection transmission, person-to-person in Niger and zoonotic in Vietnam.