Hepatitis C virus prevalence and genetic diversity among pregnant women in Gabon, central Africa

Underestimation of hepatocellular carcinoma incidence resulting from a competition between modern and traditional medicine: the case of Gabon

Primary liver cancer, particularly hepatocellular carcinoma (HCC), remains a major killer in sub-Saharan Africa. In this dreadful landscape, West and Central Africas are more particularly affected. However, a small country located on the equator, Gabon, is apparently not concerned by this adverse situation. Despite worrying prevalences of many bona fide risk factors of HCC, including high rates of chronic infections with hepatitis viruses and very high alcohol consumption, Gabon presents theoretically an amazingly low incidence of HCC when compared to other countries of the region. Reports from many places in the world have emphasized the widespread underreporting of HCC cases presumably attributable to the difficulties of proper diagnosis or to a lack of local cancer registry. In Gabon, the remarkably vivid tradition of religious initiation called Bwiti includes some therapeutic rituals exerted by healers or Ngangas. Those treatments are particularly popular in case of severe diseases generally associated with a supernatural etiology. In the present paper, we hypothesize that, in Gabon, the remarkably low incidence of HCC is primarily due to the diversion of patients from the modern medical system due to their preference for Ngangas. Promotion of a form of medical syncretism respecting both systems might be an efficient policy to increase the attractiveness of modern medicine and to ultimately promote public health in Gabon.

[Prevention and factors associated with anti-HCV carriage in pregnant women living in Cotonou]

Introduction

hepatitis C is an infection which can be passed from mother to child. The purpose of this study was to investigate the prevalence of colonization by anti-HCV antibodies in pregnant women living in Cotonou and to identify factors associated with it.

Methods

we conducted a cross-sectional study of 253 pregnant women admitted for prenatal care in four major maternity hospitals in Cotonou (Benin) from 01/06/2018 to 01/09/2018. Anti-HCV antibodies were detected using rapid diagnostic tests. A venous blood sample was collected from pregnant women tested positive for anti-HCV before confirmatory serological tests and screening tests for gestational diabetes.

Results

the prevalence of anti-HCV antibodies was 1.2% (3/253 pregnant women). Factors associated with HCV carriage couldn't be identified given the low number of positive cases. However, pregnant women who were carriers of hepatitis C antibodies had higher mean age (32 ± 3) compared to the remainder of the population (29.58 ± 5.5). Potential risk factors for HCV infection were scarifications, piercing, tattooing, sharing of manicure equipment, a history of surgery and blood transfusions. The prevalence of gestational diabetes in our study population was 7.9% (20/253). No association was found between gestational diabetes and hepatitis C.

Conclusion

the prevalence of anti-HCV antibodies in pregnant women living in Cotonou was low. A national-level study is needed to identify factors associated with this infection.

Perinatal transmission of hepatitis C virus: an update

Infection with hepatitis C virus (HCV) is a major health problem worldwide. A large proportion of perinatal HCV infections are silent and may present later in adulthood with long-term complications. HCV has no effective immune prophylaxis and hence appropriate follow-up of all infants born to HCV-infected mothers is necessary. Universal antenatal screening for HCV is largely debatable. Intrauterine and partum transmission of HCV are both possible and higher rates are associated with a high maternal serum viral load (> 10⁶ copies per milliliter), concomitant HIV infection, prolonged or difficult delivery, and invasive fetal monitoring during delivery. Infection during pregnancy and infancy needs to be investigated more in order to design management strategies for perinatal transmission of HCV most effectively. The recently approved new-generation, oral, direct-acting antiviral drugs may open a new era in HCV therapy for pregnant women and infected infants if proved to be safe during conception and infancy.

Characterization of demographics and NS5A genetic diversity for hepatitis C virus genotype 4-infected patients with or without cirrhosis treated with ombitasvir/paritaprevir/ritonavir

Hepatitis C virus (HCV) genotype 4 (GT4) is genetically diverse with 17 confirmed and 4 provisional subtypes. In this report, HCV GT4-infected patient samples from Phase 2/3 clinical studies were analysed to characterize global demographics and genetic diversity of GT4 infection among patients treated with ombitasvir (OBV, NS5A inhibitor) plus paritaprevir/r (NS3/4A inhibitor codosed with ritonavir). Among 17 subtypes isolated from GT4-infected patients in the PEARL-I and AGATE-I studies, subtype prevalence by country of enrolment and country of origin suggested that subtypes 4a and 4d were likely circulating in Europe, while heterogeneous GT4 subtypes and a portion of GT4a detected in European and North American countries were likely due to immigration of HCV-infected patients from Africa. The distributions of birth cohort and race were also significantly different across GT4 subtypes 4a, 4d, and non-4a/4d. In addition, phylogenetic analyses of NS5A sequences revealed clustering within subtype 4a which segregated by the patient-reported country of origin and the presence of the L30R/S polymorphism. HCV NS5A sequences derived from GT4a-infected patients who originated from Europe and the United States clustered separately from sequences derived from patients who originated from Egypt, suggesting that genetically distinct strains of subtype 4a may be circulating globally. Finally, NS5A baseline polymorphisms were frequently detected at amino acid positions of interest for the inhibitor-class and OBV retained activity against 37 of 39 NS5A GT4 clinical isolates, with no impact on treatment outcome in the PEARL-I and AGATE-I studies.

Low prevalence of HCV infection with predominance of genotype 4 among HIV patients living in Libreville, Gabon

Background

Gabon is an endemic area for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) and the risk of co-infection is high.

Method

Between November 2015 and April 2016, we conducted retrospective study on HCV infection among people living with HIV/AIDS (PLHA). A total of 491 PLHA were included in this study and tested for the presence of HCV infection. HIV viral loads were obtained using the Generic HIV viral Load® assay and the CD4+ T cells count was performed using BD FACSCount™ CD4 reagents. HCV screening was performed using the MP Diagnostics HCV ELISA 4.0 kit. HCV genotypes were determined by sequence analysis of NS5B and Core regions. The Mann-Whitney test was used to compare the groups. Chi-2 test and Fisher's Exact Test were used to compare prevalence.

Results

HCV seroprevalence was 2.9% (14/491), (95% confidence interval (CI):1.4–4.3%). The percentage of HCV viremic patients, defined by the detection of HCV RNA in plasma, was 57% (8/14), representing 1.6% of the total population. HCV seroprevalence and replicative infection were not statistically differ with gender. The percentage of co-infection increased with age. No correlation with CD4+ T cells count and HIV viral load level was registered in this study. Identified HCV strains were predominantly of genotype 4 (87.5%) including 4k, 4e, 4g, 4p, 4f and 4c subtypes. Only one strain belonged to genotype 2 (subtype 2q). Analysis of the NS5B region did not reveal the presence of resistance-associated substitutions for sofosbuvir.

Conclusion

A systematic screening of hepatitis C is therefore strongly recommended as well as genotyping of HCV strains in order to adapt treatments for the specific case of people living with HIV/AIDS in Central Africa.

The epidemic dynamics of hepatitis C virus subtypes 4a and 4d in Saudi Arabia

The relatedness between viral variants sampled at different locations through time can provide information pertinent to public health that cannot readily be obtained through standard surveillance methods. Here, we use virus genetic data to identify the transmission dynamics that drive the hepatitis C virus subtypes 4a (HCV4a) and 4d (HCV4d) epidemics in Saudi Arabia. We use a comprehensive dataset of newly generated and publicly available sequence data to infer the HCV4a and HCV4d evolutionary histories in a Bayesian statistical framework. We also introduce a novel analytical method for an objective assessment of the migration intensity between locations. We find that international host mobility patterns dominate over within country spread in shaping the Saudi Arabia HCV4a epidemic, while this may be different for the HCV4d epidemic. This indicates that the subtypes 4a and 4d burden can be most effectively reduced by combining the prioritized screening and treatment of Egyptian immigrants with domestic prevention campaigns. Our results highlight that the joint investigation of evolutionary and epidemiological processes can provide valuable public health information, even in the absence of extensive metadata information.

High Prevalence and Diversity of Hepatitis Viruses in Suspected Cases of Yellow Fever in the Democratic Republic of Congo

The majority of patients with acute febrile jaundice (>95%) identified through a yellow fever surveillance program in the Democratic Republic of Congo (DRC) test negative for antibodies against yellow fever virus. However, no etiological investigation has ever been carried out on these patients. Here, we tested for hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), hepatitis D (HDV), and hepatitis E (HEV) viruses, all of which can cause acute febrile jaundice, in patients included in the yellow fever surveillance program in the DRC. On a total of 498 serum samples collected from suspected cases of yellow fever from January 2003 to January 2012, enzyme-linked immunosorbent assay (ELISA) techniques were used to screen for antibodies against HAV (IgM) and HEV (IgM) and for antigens and antibodies against HBV (HBsAg and anti-hepatitis B core protein [HBc] IgM, respectively), HCV, and HDV. Viral loads and genotypes were determined for HBV and HVD. Viral hepatitis serological markers were diagnosed in 218 (43.7%) patients. The seroprevalences were 16.7% for HAV, 24.6% for HBV, 2.3% for HCV, and 10.4% for HEV, and 26.1% of HBV-positive patients were also infected with HDV. Median viral loads were 4.19 × 10⁵ IU/ml for HBV (range, 769 to 9.82 × 10⁹ IU/ml) and 1.4 × 10⁶ IU/ml for HDV (range, 3.1 × 10² to 2.9 × 10⁸ IU/ml). Genotypes A, E, and D of HBV and genotype 1 of HDV were detected. These high hepatitis prevalence rates highlight the necessity to include screening for hepatitis viruses in the yellow fever surveillance program in the DRC.

Hepatitis C virus seroprevalence in adults in Africa: a systematic review and meta-analysis

With the introduction of more efficient treatments for hepatitis C virus (HCV), improved epidemiological information is required at the country level to allow evidence-based policymaking for elaboration of national strategies and HCV resources planning. We present a systematic review with meta-analysis of HCV seroprevalence data in adults in African countries. We conducted a systematic review of all HCV seroprevalence estimates reported in African countries from 2000 to 2014 in MEDLINE, AJOL and grey literature. We assessed studies performed in the general population and among blood donors, pregnant women and HIV-positive patients. A meta-regression analysis was used to provide adjusted estimates of HCV seroprevalence in the general adult population in each country, accounting for the heterogeneity in sample age structure and population types in the included studies. We identified 775 national-level estimations, among which 184 were included. Estimates of HCV seroprevalence were produced for 38 countries, in addition to the results from nationwide representative surveys available in Egypt and Libya. Next to Egypt, which clearly stands out, the highest levels of seroprevalence were found in Middle Africa (e.g. Cameroon, Gabon and Angola) and some West African countries (e.g. Burkina Faso, Benin), and the largest absolute numbers of infected adults were found in Nigeria, Ethiopia and Democratic Republic of Congo. This study exposes the diversity of HCV epidemiology among African countries. Egypt and several countries of West and Middle Africa present a HCV burden that will require strong governmental commitment to promote efficient preventive and curative interventions.

Characteristics of anti-hepatitis C virus antibody-positive patients in a hospital setting in Douala, Cameroon

INTRODUCTION

Hepatitis C virus (HCV) infection is a major public health problem, especially in resource-limited settings where many patients are diagnosed at the stage of complications. In Cameroon, where HCV is endemic, little is known about the clinical, biological, and virological profile of HCV-infected patients.

METHODS

A clinical case note review of all patients positive for antibodies against HCV diagnosed at the gastroenterology outpatient clinic of the Douala General Hospital, Cameroon, from January 2008 to December 2014, was performed.

RESULTS

A total of 524 patients were included in the study, 53% of whom were female. The mean age was 56±13 years. A history of blood transfusion and a history of scarification were the most common potential risk factors for HCV exposure, as found in 16% and 13% of the study population, respectively. Current alcohol use was found in 24% of patients. Co-infection with hepatitis B virus and HIV was 3.6% and 3.4%, respectively. Among the patients, 39% had no complaint at diagnosis; only 16% were diagnosed through a routine medical checkup. Clinically, the most common finding was hepatomegaly (26.1% of patients). Transaminases above the upper limit of normal were found in 55.2% of patients, particularly those aged >57 years (p=0.001). Genotypes 1 (43.95%), 2 (25.11%), and 4 (28.25%) were the most common. Liver cirrhosis was present in 11% of patients and hepatocellular carcinoma in 4%, the latter being more common in males (p<0.001) and in those aged >57 years (p=0.03).

CONCLUSIONS

In the gastroenterology clinic of Douala General Hospital, while almost 40% of patients who were anti-HCV antibody-positive were asymptomatic and diagnosed fortuitously, some already presented complications, including cirrhosis and hepatocellular carcinoma. There is an urgent need to put in place programs to increase awareness and diagnosis of HCV infection and to develop extensive and targeted anti-HCV treatment guidelines to improve the management of these patients in Cameroon.

Phylogeography and epidemic history of hepatitis C virus genotype 4 in Africa

HCV genotype 4 is prevalent in many African countries, yet little is known about the genotype׳s epidemic history on the continent. We present a comprehensive study of the molecular epidemiology of genotype 4. To address the deficit of data from the Democratic Republic of the Congo (DRC) we PCR amplified 60 new HCV isolates from the DRC, resulting in 33 core- and 48 NS5B-region sequences. Our data, together with genotype 4 database sequences, were analysed using Bayesian phylogenetic approaches. We find three well-supported intra-genotypic lineages and estimate that the genotype 4 common ancestor existed around 1733 (1650-1805). We show that genotype 4 originated in central Africa and that multiple lineages have been exported to north Africa since ~1850, including subtype 4a which dominates the epidemic in Egypt. We speculate on the causes of the historical intra-continental spread of genotype 4, including population movements during World War 2.

Epidemiological profiles of human immunodeficiency virus and hepatitis C virus infections in Malian women: Risk factors and relevance of disparities

AIM: To document the epidemiologic patterns and risk factors of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections in Mali in order to develop prevention means for both diseases.

METHODS: Two prospective studies were conducted in Bamako in 2009 among 1000 pregnant women (i.e., young women) who consulted six reference health centers, and in 2010, among 231 older women who attended general practice in two hospitals. Antibody tests and molecular analysis (performed only for HCV) were used to quantify the frequencies of both infections. The data were collected from patients recruited through a questionnaire. Transmission risk factors of both diseases were identified by univariate and multivariate analysis.

RESULTS: HCV seroprevalence was 0.2% for young and 6.5% for older women. HIV prevalence was similar in both populations (4.1% vs 6.1%). In older women, the analysis of risk factors highlighted an association between HCV infection and episodes of hospitalization (P < 0.01). The study did not show an association between HIV infection and the variables such as hospitalization, transfusion, tattoo, dental care, and endoscopy. A significant decrease of HIV seroprevalence was detected in young women who used condoms for contraception more than for other purposes (P < 0.01). By contrast, HIV seroprevalence was significantly increased in young women using condoms mainly to prevent sexual infections rather than for contraception (P < 0.01). No HCV/HIV coinfection was detected in our study.

CONCLUSION: Risk factors and epidemiologic data of HIV and HCV as well as the absence of co-infection strongly suggest epidemiological disparities between these diseases.

Prevalence of HIV and HCV infections in two populations of Malian women and serological assays performances

AIM

To estimate the prevalence of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections in women in Mali and to evaluate the performance of serological assays.

METHODS

Two prospective studies were conducted in 2009 and 2010 in Mali. They concerned first, 1000 pregnant women attending six reference health centers in Bamako (Malian capital) between May 26 and June 16, 2009; and secondly, 231 women over 50 years who consulted general practitioners of two hospitals in Bamako between October 25 and December 24, 2010. Blood samples were collected and kept frozen in good condition before analysis. All samples depicted as positive using HIV/HCV enzyme immuno-assay screening assays were submitted to confirmation analysis. Molecular markers of HCV were characterized.

RESULTS

The seroprevalence of HIV and HCV in the population of pregnant women was 4.1% and 0.2% respectively. Among older women the seroprevalence was higher and similar for HIV and HCV (6.1% vs 6.5%). The anti-HIV prevalence was not different in young and older women (4.1% vs 6.1%). In contrast, the anti-HCV prevalence was higher in older compared to younger women (6.5% vs 0.2%, P < 0.01). Of 2 pregnant women who were HCV seropositive, only one was polymerase chain reaction (PCR) reactive and infected by genotype 2, with a viral load of 1600 IU/mL. Regarding older women who were HCV seropositive, 13 out of 15 were PCR reactive, infected by genotype 1 or 2. Globally HCV genotype 2 was predominant. The positive predictive value (PPV) measured with VIKIA HIV test in young women was 100% therefore significantly higher than the 87.5% measured in older women (P < 0.05). Conversely, the PPV measured with Monolisa HCV assay in older women was 88.2% and higher than the 14.3% measured in younger women (P < 0.01).

CONCLUSION

Whereas HIV prevalence was similar in both subpopulations HCV was more frequent among older women (P < 0.01). The PPV of screening assays varied with the age of the subjects.

Epidemiology and aetiology of maternal bacterial and viral infections in low- and middle-income countries

BACKGROUND

Maternal morbidity and mortality in low- and middle-income countries has remained exceedingly high. However, information on bacterial and viral maternal infections, which are important contributors to poor pregnancy outcomes, is sparse and poorly characterised. This review aims to describe the epidemiology and aetiology of bacterial and viral maternal infections in low- and middle-income countries.

METHODS

A systematic search of published literature was conducted and data on aetiology and epidemiology of maternal infections was extracted from relevant studies for analysis. Searches were conducted in parallel by two reviewers (using OVID) in the following databases: Medline (1950 to 2010), EMBASE (1980 to 2010) and Global Health (1973 to 2010).

RESULTS

Data from 158 relevant studies was used to characterise the epidemiology of the 10 most extensively reported maternal infections with the following median prevalence rates: Treponema pallidum (2.6%), Neisseria gonorrhoeae (1.5%), Chlamydia trachomatis (5.8%), Group B Streptococcus (8.6%), bacterial vaginosis (20.9%), hepatitis B virus (4.3%), hepatitis C virus (1.4%), Cytomegalovirus (95.7% past infection), Rubella (8.9% susceptible) and Herpes simplex (20.7%). Large variations in the prevalence of these infections between countries and regions were noted.

CONCLUSION

This review confirms the suspected high prevalence of maternal bacterial and viral infections and identifies particular diseases and regions requiring urgent attention in public health policy planning, setting research priorities and donor funding towards reducing maternal morbidity and mortality in low- and middle-income countries.

HCV prevalence and co-infection with HIV among pregnant women in Saint Camille Medical Centre, Ouagadougou

OBJECTIVE

To determine hepatitis C virus (HCV) prevalence and the rate of HCV/human immunodeficiency virus (HIV) co-infection in pregnant women attending Saint Camille medical centre (SCMC) in Ouagadougou.

METHODS

A total of 607 pregnant women, 16-45 years old, with <32 weeks amenorrhoea were screened for HCV and HIV using rapid tests. The majority of the women included in the study were previously known as HIV infected, as the centre is a reference centre for the programme of prevention against mother-to-child HIV transmission in the country. HCV RNA was extracted and quantified using the cDNA polymerase chain reaction with the nested primers at the 5' untranslated region. Transaminases were measured from plasma samples using spectrophotometric method.

RESULTS

Of women, 62.27% were infected with HIV. The prevalence of HCV was 2.14% in the screened pregnant women: 1.75% in HIV-negative women and 2.38% in HIV-positive ones. This prevalence is not significantly different between HIV-positive and HIV-negative pregnant women (P = 0.81). HCV RNA was found in all women with anti-HCV. A significant transaminase increase was noted in women infected with HCV (P = 0.01 and P < 0.01 for glutamic-pyruvic transaminase and glutamic-oxaloacetic transaminase, respectively). Risk factors significantly associated with HCV positivity in pregnant women included transfusion and genital excision. In addition, the infection was linked with the educational level of the women.

CONCLUSION

The issue of this study revealed that effort should be made to promote safe medical practices and fight against women genital excision that are found to be the main risk factors associated with the HCV infection.

Emerging viral threats in Gabon: health capacities and response to the risk of emerging zoonotic diseases in Central Africa

Emerging infectious diseases (EID) are currently the major threat to public health worldwide and most EID events have involved zoonotic infectious agents. Central Africa in general and Gabon in particular are privileged areas for the emergence of zoonotic EIDs. Indeed, human incursions in Gabonese forests for exploitation purposes lead to intensified contacts between humans and wildlife thus generating an increased risk of emergence of zoonotic diseases. In Gabon, 51 endemic or potential endemic viral infectious diseases have been reported. Among them, 22 are of zoonotic origin and involve 12 families of viruses. The most notorious are dengue, yellow fever, ebola, marburg, Rift Valley fever and chikungunya viruses. Potential EID due to wildlife in Gabon are thereby plentiful and need to be inventoried. The Gabonese Public Health system covers geographically most of the country allowing a good access to sanitary information and efficient monitoring of emerging diseases. However, access to treatment and prevention is better in urban areas where medical structures are more developed and financial means are concentrated even though the population is equally distributed between urban and rural areas. In spite of this, Gabon could be a good field for investigating the emergence or re-emergence of zoonotic EID. Indeed Gabonese health research structures such as CIRMF, advantageously located, offer high quality researchers and facilities that study pathogens and wildlife ecology, aiming toward a better understanding of the contact and transmission mechanisms of new pathogens from wildlife to human, the emergence of zoonotic EID and the breaking of species barriers by pathogens.

Absence of intrafamilial transmission of hepatitis C virus and low risk for sexual transmission in rural central Africa indicate a cohort effect

BACKGROUND

Intrafamilial and sexual transmission of hepatitis C virus (HCV) are still being debated, and little is known about such transmission in central Africa.

OBJECTIVE

To examine the rate of intrafamilial transmission of HCV between patients and their household members.

STUDY DESIGN

A cross-sectional study was conducted in Dienga, a remote village in Gabon, involving 195 household members of 14 index cases of HCV infection. After a questionnaire on the risk factors for parenteral exposure, blood samples were obtained and tested for antibody to HCV by an enzyme immunoassay (Monolisa anti-HCV plus version 2). Positive samples were tested for HCV RNA and genotyped by amplification and phylogenetic analysis of a fragment of the NS5B gene.

RESULTS

HCV antibody was found in 13/195 (6.7%) household contacts, comprising 5/14 (35.7%) sexual partners and 8/114 (7%) relatives. None of the children of index patients tested positive. HCV RNA was detected in only five household members with HCV antibody. The same genotypes were found in only two of five couples, both couples being sexual partners. Parenteral risk factors were not more likely to be reported by people positive for HCV antibody than by those who were negative. Age over 50 years was the only independent predictor of positivity for HCV antibody.

CONCLUSIONS

This study indicates, as previously suggested, that the spread of HCV in central Africa is due to a cohort effect, with previous, possibly iatrogenic, transmission rather than intrafamilial or sexual transmission.

Molecular and contextual markers of hepatitis C virus and drug abuse

The spread of hepatitis C virus (HCV) infection involves a complex interplay of social risks, and molecular factors of both virus and host. Injection drug abuse is the most powerful risk factor for HCV infection, followed by sexual transmission and additional non-injection drug abuse factors such as co-infection with other viruses and barriers to treatment. It is clearly important to understand the wider context in which the factors related to HCV infection occur. This understanding is required for a comprehensive approach leading to the successful prevention, diagnosis, and treatment of HCV. An additional consideration is that current treatments and advanced molecular methods are generally unavailable to socially disadvantaged patients. Thus, the recognition of behavioral/social, viral, and host factors as components of an integrated approach to HCV is important to help this vulnerable group. Equally important, this approach is key to the development of personalized patient treatment - a significant goal in global healthcare. In this review, we discuss recent findings concerning the impact of drug abuse, epidemiology, social behavior, virology, immunopathology, and genetics on HCV infection and the course of disease.