Dora Mbanya

Blood safety in Sub-Saharan Africa: a multi-factorial problem

Although the World Health Organization (WHO) has set targets for safe blood by 2012, Sub‐Saharan Africa remains confronted with multi‐factorial issues that compromise blood safety in most countries of the region. Some of these include the development and implementation of national policies for transfusion, the recruitment of voluntary and unpaid donors, proper screening of collected blood as well as a strategy for its rational use in a setting already plagued by a high prevalence of blood‐borne agents, poverty, and sometimes organizational deficits. Furthermore, the organization of hemovigilance, as well as quality systems that could monitor transfusion practices is lacking in these settings. There is no funding and global improvement of blood safety has to be cheap to be feasible. Specific solutions for the African continent need to be developed and implemented. This paper examines the current status and difficulties of blood safety in Africa and reviews available data on transfusion medicine in the region.

The prevalence of diverse HIV-1 strains was stable in Cameroonian blood donors from 1996 to 2004.

Objective:The HIV epidemic in Cameroon is characterized by a high level of strain diversity despite a relatively low prevalence of infection. In this study, HIV strains infecting blood donors in Cameroon were characterized to determine the prevalence of subtypes and intersubtype recombinants and if strain prevalence was changing over time. Methods:From 1996 through 2004, 676 HIV-infected blood donations were collected at blood banks in Douala and Yaoundé, Cameroon. A subset of the HIV-1 group M strains (n = 574) were classified based on phylogenetic analysis of viral sequences from the gag p24, pol integrase, and env gp41 regions. Results:HIV-1 group M accounted for 97.3% (n = 658) of infections, whereas group O was present in 2.2% (n = 15) and HIV-2 in 0.4% (n = 3). Within the group M infections, 14 subtypes and circulating recombinant forms (CRFs) and unique recombinant forms (URFs) were identified. Overall, CRF02_AG accounted for 58.2% of infections, URFs 14.8%, and levels of subtypes, A, B, C, D, F2, and G, and CRFs, 01, 06, 09, 11, 13, 22, and 37, varied from 0.2% to 6.1%. Evaluation of HIV strains present in the donor population over this 9-year period showed no substantial changes in the proportion of infections caused by each subtype and CRF, the percentage of intersubtype recombinants, or the strain composition of the URFs. Conclusions:HIV-1 strain diversity in Cameroon did not significantly change, suggesting a mature and relatively stable epidemic.

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.

Four new HIV-1 group N isolates from Cameroon: prevalence continues to be low.

Analysis of 3555 HIV-seropositive specimens, collected in Cameroon from 2002 to 2006, led to the identification of four HIV-1 group N infections based on differential seroreactivity to HIV env-derived peptides and proteins and confirmation by nucleic acid amplification. Group N prevalence continues to be low accounting for only 0.1% of HIV infections in Cameroon. Near full-length genomic sequences were obtained from viral RNA or proviral DNA by PCR amplification of overlapping fragments for three isolates, 06CM-U14296, 06CM-U14842, and 02CM-SJGddd. Two genome segments, partial pol and env-nef, were obtained from viral RNA for the fourth isolate, 02CM-TIM0217. With the four group N isolates identified in this study and group N sequences previously reported, eight near full-length and five partial genome sequences are now available. Despite genetic divergence from HIV-1 group M and O, all of the group N infections evaluated by five commercial HIV immunoassays were detected.

External Financial Aid to Blood Transfusion Services in Sub-Saharan Africa: A Need for Reflection

Jean-Pierre Allain and colleagues argue that, while unintended, the foreign aid provided for blood transfusion services in sub-Saharan Africa has resulted in serious negative outcomes, which requires reflection and rethinking.

Emergence of antiretroviral therapy resistance-associated primary mutations among drug-naive HIV-1-infected individuals in rural western cameroon

Summary: The prevalence of antiretroviral therapy (ART) resistance-associated mutations among HIV-1 strains in western Cameroon was evaluated by genotypically analyzing strains isolated from drug-naive individuals. Proviral DNA was extracted from 54 blood samples and amplified by polymerase chain reaction of protease, reverse transcriptase, integrase, and envelope genes. At least 4 clones per sample were analyzed. Of 54 HIV-1 strains, 45 (83.3%) had a concordant subtype or circulating recombinant form (CRF) designation: 40 CRF02_AG, 2 subtype A1, 2 G, and 1 F2. The remaining 9 (16.7%) had a discordant subtype: 6 subtype A1/CRF02_AG, 2 D/CRF02, and 1 G/CRF02. Protease inhibitor-associated primary resistance mutations were found in 4 (7.4%) cases: M46L with full clones in 1 case, and M46I, M46L, and V82A as minor populations in 1 case each. Reverse transcriptase inhibitor-associated primary resistance mutations were found in 5 (9.8%) samples: Y188C in 2 cases, and L100I, M184V, and V75I in 1 case each, although all of these mutations were found as minor populations. This is one of the first reports of the emergence of primary ART resistance mutations among drug-naive, non-B subtype HIV-1-infected individuals in Cameroon. Follow-up studies should be conducted to assess whether these drug-resistant mutants found as minor populations might impact future ART.

Ebola: a call for blood transfusion strategy in sub-Saharan Africa

WHO has stated that convalescent blood or plasma is an option in the treatment of Ebola. In 1999, transfusion of locally collected convalescent blood helped decrease Ebola mortality. WHO recommends collection of convalescent plasma to treat patients in the fi ght against the Ebola outbreak. As there is an estimated 70% mortality, a randomised clinical evaluation involving 50 patients, receiving convalescent and control normal plasma, would be suffi cient to confi rm the usefulness of this approach in treatment strategies. Capacity building for the collection and testing of suffi cient convalescent blood or plasma from recovered Ebola patients is crucial. However, paradoxically, the outbreaks are occurring in the countries that have the least capability for blood and plasma collection or viral screening, and which lack infrastructure, equipment, and trained personnel. To ensure collection of safe convalescent plasma, donors must be clinically and virally free of Ebola Virus Disease (EVD) and other relevant viruses. Convalescent plasma is the preferred product, either fresh or fresh-frozen, collected by plasmapheresis with out compromising the donor’s haemoglobin level. Plasmapheresis provides large volumes (500 ml) and can usually be repeated at 2–3 day intervals. Donors selected from the same geographical area are recommended and can provide treatment for many patients. In most African countries there is a paucity of expertise, infrastructure and equipment; however, plasmapheresis equipment can be donated and training provided in-country or at regional Blood Services. Portable generators can provide power for equipment and refrigerators. The Ebola emergency shows the importance of strengthening the technical capacity and infrastructure of local transfusion systems, to respond to present and future infectious outbreaks. The importance of ensuring adequate, accessible, and safe blood—in all countries—is a global priority. Whole blood and labile blood components are now on the WHO’s Essential Medicines List (EML), emphasising the crucial role of transfusions in public health. In sub-Saharan Africa, whole blood, when available, is a life-saving product for emergency use that, together with convalescent plasma, might be the only available clinical option in the treatment of Ebola patients at present. National governments should develop sustainable local blood services for an adequate supply of safe blood as a priority. WHO’s urgent appeal, supporting the use of convalescent blood products to fight Ebola, is a timely reminder of the many World Health Assembly resolutions supporting such actions, particularly in low resource countries.

Reduction of the risk of transfusion-transmitted human immunodeficiency virus (HIV) infection by using an HIV antigen/antibody combination assay in blood donation screening in Cameroon.

BACKGROUND: Improving blood safety without introducing nucleic acid testing in blood screening may be possible using antigen/antibody (Ag/Ab) combination assays, especially in resource‐poor countries.

HIV type 2 intergroup recombinant identified in Cameroon.

A unique HIV-2 intergroup recombinant strain was identified in Cameroon. The virus, CM-03-510-03, was amplified from blood collected from a 47-year-old female patient in Douala, Cameroon in 2003 who was seroreactive for HIV-2. A near full-length genome 9089 nucleotides in length was amplified from proviral DNA. The genome for CM-03-510-03 is composed of segments of HIV-2 groups A and B with four recombination break-points and has open reading frames for all the structural and regulatory genes. A comparison of CM-03-510-03 to the only previously reported HIV-2 intergroup recombinant shows that the two strains share one recombination breakpoint but are otherwise distinct from each other. Similar to HIV-1, HIV-2 intergroup recombination is an indication that coinfection with more than one strain has occurred in individuals and is a mechanism that increases strain genetic diversity.

Utility of Metagenomic Next-Generation Sequencing for Characterization of HIV and Human Pegivirus Diversity

Given the dynamic changes in HIV-1 complexity and diversity, next-generation sequencing (NGS) has the potential to revolutionize strategies for effective HIV global surveillance. In this study, we explore the utility of metagenomic NGS to characterize divergent strains of HIV-1 and to simultaneously screen for other co-infecting viruses. Thirty-five HIV-1-infected Cameroonian blood donor specimens with viral loads of >4.4 log10 copies/ml were selected to include a diverse representation of group M strains. Random-primed NGS libraries, prepared from plasma specimens, resulted in greater than 90% genome coverage for 88% of specimens. Correct subtype designations based on NGS were concordant with sub-region PCR data in 31 of 35 (89%) cases. Complete genomes were assembled for 25 strains, including circulating recombinant forms with relatively limited data available (7 CRF11_cpx, 2 CRF13_cpx, 1 CRF18_cpx, and 1 CRF37_cpx), as well as 9 unique recombinant forms. HPgV (formerly designated GBV-C) co-infection was detected in 9 of 35 (25%) specimens, of which eight specimens yielded complete genomes. The recovered HPgV genomes formed a diverse cluster with genotype 1 sequences previously reported from Ghana, Uganda, and Japan. The extensive genome coverage obtained by NGS improved accuracy and confidence in phylogenetic classification of the HIV-1 strains present in the study population relative to conventional sub-region PCR. In addition, these data demonstrate the potential for metagenomic analysis to be used for routine characterization of HIV-1 and identification of other viral co-infections.