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Unlabelled: The broad use of cytomegalovirus (CMV) viral load quantification in blood to follow immunosuppressed patients need standardized assays. Choice of whole blood allows follow-up for several viruses and simplifies pretreatment and storage of samples., Methods: We therefore evaluated the LightCycler CMV Quant Kit (Roche Diagnostics) assay on whole blood after a manual extraction (High Pure viral nucleic acid kit, Roche Diagnostics), using as a reference an in-house Taqman assay (LC1UL83) which has been validated in various clinical situations. A panel obtained by serial dilutions of a virion stock in CMV whole blood, a commercial plasma quality control (VQC, Argène, France) crude or diluted in whole blood, infected cells extracts and 46 clinical samples from transplanted patients were tested simultaneously by both techniques., Results: For plasma quality controls, both PCR assays are correlated VQC (R(2)=0.93). On whole blood or infected cells dilutions, correlation shows an overestimation by the LC1UL83 assay (mean 1.2 log copies/ml) over 3 log though R(2)=0.94. Results with CMV Quant Kit are closer to expected values. Results on clinical samples are close to quality controls with a lower variation of quantification (0.76 log copies/ml)., Conclusion: CMV Quant Kit performs well when compared with a clinically validated PCR. Quality control results showed discrepancies between plasma and whole blood, demonstrating the need for whole blood standardized panels to compare the methods. This underlines the need to follow a patient with the same technique during his follow-up., (Copyright 2009 Elsevier Masson SAS. All rights reserved.)

Background and Aim: Using of safety blood products did not stop improving these last years. The use of effective methods as well immunologicals as virologicals ones really reduces risk associated to blood transfusion. However, it persists residual risk (RR) of transfusion transmitted viral diseases. The aim of our study was to detect cases of seroconversion for HIV,and HBV among donors in the Senegalese national blood bank. And then, we estimated the RR of these virus., Methods: We led a transverse retrospective study from 2003 (January 1st) to 2005 (December 31st). Had been included donors with at least two donations of blood during the period of study. They had to be seronegative for HIV and HBV after the first donation. All donors with only one donation had been excluded. RR was estimated by multiplying incidence rates by the durations of the window periods., Results: During 3 years, we collected 425,503 donations; 388 were positive for HIV and 4240 for HBV. But we noted only two cases of seroconversion for HIV and 23 for HBV. So, RR estimated was 3,5 in 100,000 donation for HIV and 102,45 in 100,000 donations for VHB., Conclusion: It emerges from this study that the risk of blood transmitted virus is always high. Introduction of more sensitive tests (as nucleic acid testing) would allow us to deliver more safety products.

We report the successive stages of the reorganization of the blood transfusion sector in Togo. The starting point was the elaboration of the national policy of blood transfusion, then the adoption of a decree organizing the sector as well the various decree of application, particularly that related to transfusion good practices. The current policy recommends two poles of qualification of the blood ant its components and the creation of six stations of collection and distribution attached to these poles. The reorganization started with the rehabilitation of the National Blood Transfusion Centre (CNTS) in Lomé. If the problem of human resources is alarming, especially the availability of hemobiologists, the rehabilitation allowed the increase of the blood collection passing from 5272 donations in December 2003 to 18 164 in December 2008. However, the requirement of blood products is satisfied in 50% in all the country. In 2003, 24% of the blood products were rejected for positive viral markers against 8.37% in 2008 in relation with the improvement of blood safety. Efforts must be continued to reinforce it in the CNTS and to make a better selection of the donors at the Regional Blood Transfusion Centre (CRTS) de Sokodé. The analysis of the weak points of the sector (human resource insufficiency, shortage of the blood products, blood safety) made it possible to indicate solutions to improve the sector of blood transfusion sector. Future outcome is funded in the blood transfusion safety development project in Togo financed by the Agence française de développement (AFD, French development agency).

In subsaharan Africa, knowledge of the organization and methods of transfusion centers, as well as blood donor characteristics, is essential in choosing strategies to improve transfusion practices and the security of blood products on this Continent. The present study was based on a analysis led in partnership with the transfusion of seven francophone African countries (Burkina-Faso, Cameroon, Congo, Ivory Cost, Mali, Niger, and Rwanda). The results showed that withstanding significant progress has been realized in the organization and safety, but much remains to be undertaken over the years to come in order to improve the organization of the centers, the providing of blood products and the infectious and immunohematologic safety. This evolution, for the moment, is limited by the financial resources, insufficient training of personnel and cultural obstacles, but will necessarily pass through the pursuit of conjugated efforts of the scientific, international and local communities.

The occurrence of asymptomatic penetration of certain infectious agents in blood presents a risk of transmission of one of these agents during blood transfusion. Although well controlled for some infectious agents (HIV, HTLV, HCV, HBV), this risk is nevertheless neither documented nor quantified for other pathogens that are responsible for serologically unscreened or undetectable infections at the time of blood donation. This risk is generally low in endemic situations, although it increases for particular time periods and locations when clustered cases or outbreaks occur. Prevention measures may then be implemented (interruption of blood collection, quarantined donations, etc.). These measures can have an important impact, particularly by limiting the supply of blood products to health care facilities. It is therefore important for these measures to be adapted to the risk of transmission through blood transfusion. Quantitative risk estimates of blood donation contamination can therefore contribute to guiding those measures. In this context, in early 2005, the French Public Health Institute (InVS) started a project with the aim of obtaining a priori quantitative risk estimates of contamination of a blood donation by infectious agents for various scenarios in terms of incidence and time-space distribution. The objective of this article is to update the last estimates of residual risks of the major transfusion-transmitted viral infections (HIV, HTLV, HCV and HBV) and to present the work realized by the working group << Quantitative estimate of the risk of blood donation contamination by infectious agents>>.

Bacterial contamination of blood components represents today the highest infectious risk in blood transfusion, the risk is particularly high when it affects platelet concentrates. The prevention methods developed over the past ten years (donor selection, phlebotomy site preparation, first 30 ml diversion, systematic leuko-reduction...) which aimed at limiting the introduction of bacteria in donations and bacterial proliferation, has reduced the risk of transfusion reaction due to the bacterial contamination. Improving strategies for reducing the risks of bacterial contamination is one of the priorities of the French National Blood Transfusion Service (l'Etablissement français du sang - EFS). It is essential to improve existent prevention methods and develop the implication of all the actors (from donation to transfusion) involved in the prevention of this risk. Bacterial detection or pathogens inactivation are now available and are able to reduce (for detection) or prevent (for inactivation) the occurrence of reaction due to bacterial contamination of PC. Up to now, the choice is in favour of bacterial detection. Three methods (BacT/Alert, BioMerieux; eBDS, Pall; ScanSystem, Hemosystem) of detection of bacterial contamination in PC can be generalised now. Adaptations, need for their implementation are acceptable, especially concerning PC availability.

Noma is a devastating gangrenous disease that leads to severe tissue destructions in the face. It is seen almost exclusively in children living in less developed countries. The exact prevalence of the disease is unknown and the cause remains unknown too. Risk factors are: malnutrition, a compromised immune system, poor oral hygiene and a lesion of the gingival mucosal barrier, as well as an unidentified bacterial factor. Herpes viruses might also contribute. Studies of the buccal flora in acute phases of noma and comparison with control children do not exist. Our study takes place in Niger. For each child (cases and controls) we take samples of gingival fluid, saliva, blood and mouth mucosal swabs. The samples are analysed in Geneva in different laboratories. We control the serologies for Herpes viruses and measles. We also perform a nutritional assessment and the mucosal swabs are cultivated for the presence of viruses. The gingival flora is investigated by microarrays. These microarrays are instrumental to test for the presence of thousands of different bacteria in each clinical sample. This method allows a qualitative and quantitative description of the oral flora in noma-children and control cases. This is the first large scale study on the etiology of noma which uses new technical approaches for humanitarian purposes.

AN UBIQUITOUS VIRUS: The family of hepatitis viruses now has a new member discovered in 1997 by a Japanese team. The TTV (transmitted transfusion virus) is a small ubiquitous DNA virus probably largely distributed throughout the world. Prevalence in blood donors is about 2 to 10%. TRANSMISSION AND PERSISTENCE: TTV is generally transmitted via the parenteral route but can probably be transmitted via orofecal and matemo-fetal routes. The natural history of TTV has been studied in retrospective studies, particularly in hemophiliacs. After a post-transfusional peak, the virus appears to persist for long periods in the organism without causing liver damage nor any change in transaminase levels., Pathogenicity: Although no proof is yet available, the TTV does probably not have any intrinsic pathogenic power. It would rather be a ìsurrogate virusî transmitted at the same time as another virus yet to be discovered and which causes the rare cases of non A-non-G post-transfusional hepatitis.

In order to provide greater safety in blood transfusions, public health authorities have imposed the use of screening tests. The purpose of this paper is to estimate the cost-effectiveness ratios of the screening test used in France. Four risks were studied: HIV, HBV, HCV and HTLV. Two efficiency measures were used: cost per positive blood donation detected and cost per case of prevented infection transmission. Moreover, for HTLV alone, the efficiency was estimated by the cost per prevented pathology. Data concerning the costs were provided by the French Blood Agency; those concerning the results of the screening campaigns were provided by the official health authorities, the other data used in the calculations were drawn either from the French Blood Agency data or from a review of international literature. Results gave information about the expenditure devoted to the screening of virologic risks associated with blood transfusion in France (250 million francs per year for the four viruses studied). They stressed the differences in screening efficiency according to the test studied (the cost by prevented seroconversion varied from 31,795 francs for HBV, 72,180 francs for HCV, 676,596 francs for HIV to 6,137,346 francs for HTLV screening test in the base case) and especially the very low efficiency of the systematic screening of the HTLV virus (from 34 to 307 million francs per prevented leukemia).

Venezuelan equine encephalitis (VEE) is a mosquito-borne viral disease that occurs in equine species and in man. The strains can be grouped epidemiologically into two major categories: enzootic and epizootic. Enzootic strains cause sporadic human disease and are not associated with disease among equines. These strains are found throughout Florida. Central America, northern South America and Brazil. Epizootic strains are associated with enormous morbidity and mortality in equine species. In man, VEE virus infections are largely asymptomatic and in children and young adults there is an increased risk of encephalitis and dead. We report the first case in French Guiana of Venezuelan equine encephalitis. Clinical examination and biological studies showed encephalitis, interstitial pneumonia and acute liver failure. Despite an adequate symptomatic treatment, the young patient died five days after her admission in multiple organ dysfunction syndrome. Diagnosis is establishing by virologic test: VEE virus is isolated from the blood. These example of re-emerging infectious disease vividly illustrate that we remains vulnerable and emphasizes the need for an active surveillance system.