Implementation of broad screening with Ebola rapid diagnostic tests in Forécariah, Guinea.

BACKGROUND: Laboratory-enhanced surveillance is critical for rapidly detecting the potential re-emergence of Ebola virus disease. Rapid diagnostic tests (RDT) for Ebola antigens could expand diagnostic capacity for Ebola virus disease. OBJECTIVES: The Guinean National Coordination for Ebola Response conducted a pilot implementation to determine the feasibility of broad screening of patients and corpses with the OraQuick® Ebola RDT. METHODS: The implementation team developed protocols and trained healthcare workers to screen patients and corpses in Forécariah prefecture, Guinea, from 15 October to 30 November 2015. Data collected included number of consultations, number of fevers reported or measured, number of tests performed for patients or corpses and results of confirmatory RT-PCR testing. Data on malaria RDT results were collected for comparison. Feedback from Ebola RDT users was collected informally during supervision visits and forums. RESULTS: There were 3738 consultations at the 15 selected healthcare facilities; 74.6% of consultations were for febrile illness. Among 2787 eligible febrile patients, 2633 were tested for malaria and 1628 OraQuick® Ebola RDTs were performed. A total of 322 OraQuick® Ebola RDTs were conducted on corpses. All Ebola tests on eligible patients were negative. CONCLUSIONS: Access to Ebola testing was expanded by the implementation of RDTs in an emergency situation. Feedback from Ebola RDT users and lessons learned will contribute to improving quality for RDT expansion.

Seroprevalence and incidence of transfusion-transmitted infectious diseases among blood donors from regional blood transfusion centres in Burkina Faso, West Africa.

BACKGROUND AND OBJECTIVE: The high prevalence of numerous transfusion-transmitted infectious diseases such as HIV, HBV, HCV and syphilis in sub-Saharan Africa affects blood safety for transfusion recipients. The aim of this study was to evaluate the prevalence and incidence of transfusion-transmissible infectious diseases among blood donors in Burkina Faso. METHODS: A retrospective study of blood donors' records from January to December 2009 was conducted. Prevalence and incidence of viral infections were calculated among repeat and first-time blood donors. RESULTS: Of the total of 31405 first-time volunteer blood donors in 2009, 24.0% were infected with at least one pathogen and 1.8% had serological evidence of multiple infections. The seroprevalence of HIV, HBV, HCV and syphilis in first-time volunteer donors was 1.8%, 13.4%, 6.3% and 2.1%, respectively. In 3981 repeat donors, the incidence rate was 3270.2, 5874.1 and 6784.6 per 100000 donations for anti-HIV-1, HBsAg and anti-HCV, respectively. These numbers varied significantly according to populations where blood is collected and blood centres in Burkina Faso. CONCLUSION: The relatively high prevalence of viral markers in first-time volunteers and remarkably high incidence of infections in repeat donors raise concerns regarding the safety of these donors and suggest that implementation of NAT might significantly improve the situation.

Seroprevalence of human immunodeficiency virus, hepatitis B and C viruses and syphilis among blood donors in Koudougou (Burkina Faso) in 2009.

BACKGROUND: The high prevalence of numerous transfusion-transmitted infectious diseases such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis in sub-Saharan Africa affects the safety of blood for recipients. This study was undertaken with the aim of determining the seroprevalence of HIV, HCV, HBV, syphilis and socio-demographic risk factors associated with blood donation in a new regional blood transfusion centre in Burkina Faso. MATERIAL AND METHODS: Sera samples were screened for hepatitis B surface antigen (HBsAg), antibodies to HCV, HIV types 1 and 2 and to Treponema pallidum using enzyme-linked immunosorbent assays and Rapid Plasma Reagin test (RPR) respectively. All the reactive samples for HIV, HBsAg, and HCV were confirmed using a second enzyme-linked immunosorbent assays. Antibodies to Treponema pallidum were confirmed with a Treponema pallidum haemagglutination test (TPHA). RESULTS: From the total of 4,520 blood donors in 2009, 1,348 (29.82%) were infected with at least one pathogen and 149 (3.30%) had serological evidence of multiple infections. The overall seroprevalence rate of HIV, HBV, HCV and syphilis was 2.21%, 14.96%, 8.69% and 3.96%, respectively. Among blood donors with multiples infections, the most common dual or triple combinations were HBsAg-HCV (1.39%), HBsAg-syphilis (0.66%) and HBsAg-HCV-syphilis (0.11%). The highest prevalences of HBsAg and HIV were found among blood donors from rural areas and in the age groups of 20-29 years and >40 years old, respectively. CONCLUSION: HBV and HCV remain the greatest threats to blood safety in Burkina Faso. Strict selection and retention of voluntary, non-remunerated low-risk blood donors are recommended to improve blood safety in the regional blood transfusion centre of Koudougou.

Low genetic diversity despite hyperendemicity of hepatitis B virus genotype E throughout West Africa.

Sub-Saharan Africa suffers from an excessively high endemicity of hepatitis B virus (HBV), but little is known about the prevalent genotypes. In this study, we investigated the PreS1/PreS2/S genes of 127 viruses obtained from 12 locations in Mali, Burkina Faso, Togo, Benin, Nigeria, Cameroon, and the Democratic Republic of Congo. Except for those obtained from the Cameroon HIV cohort (18/22 HBV genotype A), 96 of 105 sequences belonged to HBV genotype E (HBV/E), and viral DNA was very similar (1.67% diversity) throughout this vast HBV/E crescent, which spans 6000 km across Africa. The low diversity suggests that HBV/E may have a short evolutionary history. Considering a typical mutation rate of DNA viruses, it would take only 200 years for the strain diversity of HBV/E viruses to develop from a single introductory event. The relatively recent introduction of HBV/E into humans would also explain its conspicuous absence in the Americas, despite the forced immigration of slaves from west Africa, until the early 19th century. Infection during infancy is mostly associated with chronic carrier status, and this combination can account for the explosive spread of virtually identical viruses within a community, but whether other routes of long-range transmissions must be considered becomes an important question.

Limited diversity of measles field isolates after a national immunization day in Burkina Faso: progress from endemic to epidemic transmission?

Despite recent National Immunization Days in Burkina Faso, the rural province of Houët reported >400 measles cases in 2001 (82% not vaccinated). Phylogenetic analysis of 58 measles virus field isolates plus the first sequences from the Democratic Republic of the Congo and the Republic of Congo are reported. All viruses were genotype B3, which is common in the region. In Houët, there were two geographically confined genetic variants, suggesting two independent importation events. Strain diversity in Houët (1.5%) and the Congos was limited in comparison with Ibadan, Nigeria (4.6%), where measles is endemic. Strain variability, assessed by heteroduplex mobility assay, confirmed these findings. Despite large local pools of susceptible persons even after several rounds of vaccination, the limited strain diversity suggests that parts of rural Burkina Faso may be moving from an endemic to an epidemic transmission pattern of measles virus.