New insights into Human Pegivirus-1 (HPgV-1) genotypes diversity in sub-Saharan Africa.

In the framework of a viral discovery research program using metagenomics, Human Pegivirus-1 reads (HPgV-1, formerly known as GBV-C) were detected in plasma pools of healthy blood donors from seven sub-Saharan African countries. For five of these countries, Mauritania, Mali, Niger, Burundi and Madagascar, no data about HPgV-1 genotypes was reported to date. To confirm our metagenomic findings and further investigate the genotype diversity and distribution of HPgV-1 in Africa, 400 blood donations from these five localities as well as from Cameroon, the Democratic Republic of Congo (DRC) and the Burkina Faso were screened with a RT-nested PCR targeting the viral 5'NCR region. Amplified products were sequenced, and the virus was genotyped by phylogenetic analysis. Out of the 400 plasma samples tested, 65 were positive for HPgV-1 RNA and 61 were successfully genotyped. Among these, 54 strains (88.5%) clustered with genotype 1, six (9.8%) with genotype 2 and one (1.6%) with genotype 5. Genotype 1 was observed in all countries studied, except in Madagascar, genotype 2 was detected in Mauritania and Madagascar, and genotype 5 in DRC. Overall, our results extend the geographic distribution of HPgV-1 in Africa and provide six additional nearly complete genomes. Considering that some HPgV-1 genotypes have been reported as potential predictive indicators of lower disease progression in HIV-1 infected subjects, further investigations should be conducted to better understand the positive impact, if any, of this virus.

Seroreactivity against Marburg or related filoviruses in West and Central Africa.

A serological survey of 2,430 archived serum samples collected between 1997 and 2012 was conducted to retrospectively determine the prevalence of Marburg virus in five African countries. Serum samples were screened for neutralizing antibodies in a pseudotype micro-neutralization assay and confirmed by enzyme-linked immunosorbent assay (ELISA). Surprisingly, a seroprevalence for Marburg virus of 7.5 and 6.3% was found in Cameroon and Ghana, respectively, suggesting the circulation of filoviruses or related viruses outside of known endemic areas that remain undetected by current surveillance efforts. However, due to the lack of validated assays and appropriate positive controls, these results must be considered preliminary.

High rate of hepatitis C virus and human immunodeficiency virus false-positive results in serologic screening in sub-Saharan Africa: adverse impact on the blood supply.

BACKGROUND: False positivity in blood screening may cause unnecessary deferral of healthy donors and exacerbate blood shortages. An international multicenter study was conducted to estimate the frequency of HCV and HIV false seropositivity in seven African countries (Burundi, Cameroon, Democratic Republic of Congo, Madagascar, Mali, Mauritania, and Niger). STUDY DESIGN AND METHODS: Blood donations were tested for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) with rapid detection tests (RDTs), third-generation enzyme immunoassays (EIAs), or fourth-generation EIAs. HCV (456/16,613 [2.74%]) and HIV (249/16,675 [1.49%]) reactive samples were then confirmed with antigen/antibody assays, immunoblots, and nucleic acid testing. Partial viral sequences were analyzed when possible. RESULTS: The HCV reactivity rate with RDTs was significantly lower than with EIAs (0.55% vs. 3.52%; p < 0.0001). The HIV reactivity rate with RDTs was lower than with third-generation EIAs (1.02% vs. 2.38%; p < 0.0001) but similar to a fourth-generation assay (1.09%). Only 16.0% (57/357) and 21.5% (38/177) of HCV and HIV initial reactive samples, respectively, were repeatedly reactive. HCV and HIV infections were confirmed in 13.2% and 13.7%, respectively, of repeated reactive donations. The predominant HCV genotype 2 and 4 strains in West and Central Africa showed high genetic variability. HIV-1 subtype CRF02_AG was most prevalent. CONCLUSION: High rates (>80%) of unconfirmed anti-HCV and anti-HIV reactivity observed in several sub-Saharan countries highlights the need for better testing and confirmatory strategies for donors screening in Africa. Without confirmatory testing, HCV and HIV prevalence in African blood donors has probably been overestimated.

Serologic Prevalence of Ebola Virus in Equatorial Africa.

We conducted a serologic survey of 2,430 serum samples collected during 1997-2012 for various studies to determine the prevalence of the hemorrhagic fever virus Ebola virus (EBOV) in equatorial Africa. We screened serum samples for neutralizing antibodies by using a pseudotype microneutralization assay and a newly developed luciferase immunoprecipitation system assay. Specimens seroreactive for EBOV were confirmed by using an ELISA. Our results suggest a serologic prevalence of 2%-3.5% in the Republic of the Congo and the Democratic Republic of the Congo, which have reported outbreaks of infection with EBOV. In addition we detected a seroprevalence of 1.3% in southern Cameroon, which indicated a low risk for exposure in this region.

Transfusion safety in francophone African countries: an analysis of strategies for the medical selection of blood donors.

BACKGROUND: The goal of selecting a healthy blood donor is to safeguard donors and reduce the risks of infections and immunologic complications for recipients. STUDY DESIGN AND METHODS: To evaluate the blood donor selection process, a survey was conducted in 28 blood transfusion centers located in 15 francophone African countries. Data collected included availability of blood products, risk factors for infection identified among blood donor candidates, the processing of the information collected before blood collection, the review process for the medical history of blood donor candidates, and deferral criteria for donor candidates. RESULTS: During the year 2009, participating transfusion centers identified 366,924 blood donor candidates. A mean of 13% (range, 0%-36%) of the donor candidates were excluded based solely on their medical status. The main risk factors for blood-borne infections were having multiple sex partners, sexual intercourse with occasional partners, and religious scarification. Most transfusion centers collected this information verbally instead of having a written questionnaire. The topics least addressed were the possible complications relating to the donation, religious scarifications, and history of sickle cell anemia and hemorrhage. Only three centers recorded the temperature of the blood donors. The deferral criteria least reported were sickle cell anemia, piercing, scarification, and tattoo. CONCLUSIONS: The medical selection process was not performed systemically and thoroughly enough, given the regional epidemiologic risks. It is essential to identify the risk factors specific to francophone African countries and modify the current medical history questionnaires to develop a more effective and relevant selection process.

Characteristics of blood donors and donated blood in sub-Saharan Francophone Africa.

BACKGROUND: The importance of blood safety in public health was recognized long ago, and data are essential to plan strategies to improve the status. This study aims to obtain data on blood donor and blood donation characteristics that would complement blood safety data from national and international organizations. MATERIALS AND METHODS: A questionnaire was sent to seven Francophone countries (Burkina Faso, Cameroon, Congo, Ivory Coast, Mali, Niger, and Rwanda) and was structured to obtain objective data on blood donors and donated blood and in administrative and technical organization. RESULTS: The results reflect a poor level of organization of blood transfusion centers in large regions of the African continent, insufficient supply of blood products, high prevalence of transfusion-transmitted infections, limited financial resources, a lack of well-trained personnel, and cultural obstacles. Six countries had less than 50% of their personnel trained in transfusion medicine. Only one country had the entire standard operating procedure written. Female donors represented less than 30% of the donors and the range of percentage of hepatitis B found in donors was 2.76% to 18.96%. CONCLUSION: The inclusion of these regions in future blood safety surveys and in the development of national blood transfusion programs is essential and will undoubtedly require the assistance of international organizations.