We screened plasma samples (minipools of 96 samples, corresponding to 53,234 blood donations) from France that had been processed with solvent–detergent for hepatitis E virus RNA. The detection rate was 1 HEV-positive sample/2,218 blood donations. Most samples (22/24) from viremic donors were negative for IgG and IgM against HEV.

This new developed assay presents an improvement for the detection of HCV infection, especially in the early phase of infection when antibodies are undetectable. Although less sensitive than NAT, this assay could be a suitable solution for blood screening in developing countries where NAT (or HCV core antigen-specific assay) is not affordable or its implementation is not feasible.

The subtype distribution of 142 genotype 2 and 97 genotype 4 hepatitis C virus (HCV) isolates from the sera of 1,319 volunteer blood donors in France was determined by gene sequencing and by phylogenetic analysis of the NS5B region and E1 envelope. Findings underlined a wide range of subtypes in both genotypes, that is, 20 in HCV-2 and 11 in HCV-4. Eighteen of these 31 subtypes had not been defined previously. Some subtypes, that is, 2a, 2b, 2c, 2i, 2k, 4a, and 4d, showed numerous strains while subtypes in donors from West Africa or Central Africa showed an endemic profile with only a few strains. A Bayesian coalescence approach was used to estimate the demographic history of each HCV subtype. The estimated mean dates of the most recent common ancestors (MRCA) were 1,889 (confidence interval (CI), 1,842-1,930) for HCV-2a, 1,886 (CI, 1,843-1,921) for HCV-2b, 1,791 (CI, 1,699-1,848) for HCV-2c, 1,846 (CI, 1,803-1,878) for HCV-2i, 1,911 (CI, 1,879-1,937) for HCV-4a, and 1,957 (CI, 1,943-1,967) for HCV-4d. The period of spread for subtype 2b, 2c, and 2i was between 1900 and 1960 whereas rapid exponential spread for subtype 2a, 4a, and 4d occurred in the 1960s. The inferred histories of population growth indicated that transmission rates differed according to HCV subtype. These results may help to predict the future burden of HCV in France.

The kinetics of platelets labeled with indium-111 were investigated in 13 healthy subjects as well as in 9 patients in the asymptomatic interattack stage of asthma. The survival times of platelets in healthy subjects was 8.9 +/- 1 days; in asthmatic subjects it was 4.7 +/- 1.3 days (p less than 0.001). The survival curve is of a biexponential form in asthmatics, thus suggesting the presence of 2 populations: one with a short life span (23 +/- 7 h), representing a third of the total population (33 +/- 9%), and the other with a normal life span. No single preferred site of platelet sequestration was found. These results suggest the presence of functional or anatomic lesions of platelets in asthmatic patients, which can be explained only hypothetically at the present time.

International audienc

In order to increase the safety of blood products, we have developed a procedure for the virus inactivation of fresh frozen plasma. Several batches have been prepared and with the first 10 batches, each of them composed of 60 litres of plasma, we have determined a set of biological parameters. Virus inactivation was realised using TnBP (1%) and Octoxynol 9 (1%). After their elimination with castor oil using chromatography on insolubilized C18 resin, glycine was added and the pH of the plasma was adjusted to 7.4. Plastic bags were aseptically filled with a mean volume of 200 ml of plasma. The mean levels of coagulation factors were all over 0.7 U/ml and their recovery from initial plasma was nearly the same as total protein except for factor VIII:C. The net loss in factor VIII:C was 16%, when including the dilution of plasma. In vivo and in vitro tests demonstrated that in the final product there were no activated factors. As in fresh frozen plasma, the protein concentration was over 50 g/l and the potassium level lower than 5 mmol/l. According to these results, virus-inactivated plasma has the same qualities of fresh frozen plasma and could now replace it.

The new presented model provides HBV RR estimates that do not statistically differ from those obtained with the classical model; however, it provides more accurate data, especially in low endemic areas where the HBsAg incidence is low.

No abstract