[Seroprevalence of hepatitis B and C viruses, HIV-1/2 and syphilis among blood donors in the Yaoundé Central Hospital in the centre region of Cameroon]

Seroprevalence of Transfusion-Transmissible Infections among Family Replacement Donors and Voluntary Non-Remunerated Blood Donors During the COVID-19 Pandemic in Sub Saharan Africa

Introduction : According to WHO,  regular, voluntary, unpaid blood donors are the safest group of donors, as they have the lowest prevalence of blood transmitted infections. However, family/replacement blood donors is widely used in sub Saharan Africa and this practice was exacerbated during the COVID 19 pandemic. This study aimed to compare the seroprevalence of infectious markers in family replacement blood donors and voluntary non-remunerated  blood donors during the COVID 19 pandemic in a country of sub Saharan Africa.   Materials and Methods Blood donors received at the National Centre of Blood Transfusion (NBTC) of Dakar from August 1st to October 31th 2021, were included in this study. All donors completed a pre-donation questionnaire. Donors identity, epidemiological parameters, reasons for donation and laboratory results were collected in the Inlog® software of the NBTC. The serological tests for HBV, HIV and HCV were performed with chemiluminescence technology. The Rapid Plasma Reagent test was used to find out treponemal antibodies. The determination of ABO and Rh blood groups was performed using monoclonal antisera following classical hemagglutination test on a plate. Results A total of 5002 donors were collected during this COVID-19 pandemic period. Blood family/replacement donors represented 54.0% and new voluntary donors represented 52.6%. Comparison of HIV, HCV and syphilis markers seroprevalence showed no statistically significant difference between new voluntary donors and new family replacement donors (p>0.05). However, for HBV the seroprevalence was significantly higher in new family replacement donors (p=0,002). Conclusion The proper supply of blood was impacted by the COVID-19 pandemic meanwhile replacement donations had contributed to limiting the damage observed with blood shortages. However, the significant differences noted on the seroprevalences of transfusion-transmissible infections between voluntary non-paid donors and family/replacement donors strengthens WHO recommendations for the selection of volunteer non-paid donors to lower transfusion-transmissible HBV in sub Saharan Africa.                  

Genetic diversity of the human immunodeficiency virus of type 1 in Gabonese transfusional settings

BACKGROUND

The high endemicity of transfusion-transmissible infections (TTIs) in sub-Saharan Africa is a real public health problem. To reduce the risk of HIV transmission through blood donation, the NBTC of Gabon has launched in recent years a reorganization of its blood transfusion system. This study aims to characterize the molecular strains of HIV-1 circulating in donors and to estimate the risk of viral transmission.

MATERIALS AND METHODS

A cross-sectional study was carried out during the period from August 2020 to August 2021 among 381 donors who had agreed to donate blood at the National Blood Transfusion Center (NBTC). Viral load was determined by Abbott Real-Time (Abbott m2000®, Abbott) and sequencing by the Sanger method (ABI 3500 Hitachi®). The phylogenetic tree was constructed by MEGA X software. Data were checked, entered, and analyzed using SPSS version 21.0 software, with p ≤ 0.05 considered statistically significant.

RESULTS

A total of 381 donors were enrolled in the study. Among the 359 seronegative donors, five (5) seronegative donors were detected positive for HIV-1 using Real-Time PCR. The residual risk was 648 per 1,000,000 donations. The prevalence of residual infection was 1.4% [0,01; 0,03]. Sixteen (16) samples were sequenced. The strains obtained were CRF02_AG (50%), subtype A1 (18.8%), subtype G (12.5%), CRF45_cpx (12.5%) and subtype F2 (6.2%). Six sequences clustered with A1, G, CRF02_AG, and CRF45_cpx subtypes.

CONCLUSION

The residual risk of HIV-1 transmission by blood transfusion remains a concern in the Gabonese transfusional settings. A policy based on improving the current screening strategy would involve the implementation of the nucleic acid test (NAT) in order to optimize the safety of the donation by detecting the HIV-1 subtypes in circulation in the donors.

Common hepatitis B virus genotypes among blood donors in Lagos, Nigeria

BACKGROUND

Hepatitis B virus (HBV) infection is one of the public health diseases causing global health problems. It is a leading cause of cirrhosis and hepatocellular carcinoma. Blood transfusion is a major route of its transmission and screening of blood is suboptimal in our environment. Occult HBV infection describes the presence of HBV DNA in blood or liver tissue in patients who are hepatitis B surface antigen (HBsAg) seronegative. This study documented the common genotypes of HBV a blood-borne infection in the population of blood donors in Lagos.

METHODS

This was a cross-sectional study carried out at the blood donor clinics of ten Lagos State Government-owned hospitals in Lagos State. A total of 1400 participants were recruited consecutively from November 2020 to June 2021. All participants' samples were screened using Diaspot Rapid Test Kit (RTK) and Dialabenzyme enzyme-linked immunosorbent assay (ELISA) kit. Furthermore, some of the plasma samples were used for HBV DNA extraction and genotyping using the real time-polymerase chain reaction. Statistical analysis was carried out using the Statistical Package for the Social Sciences (SPSS) software version 26 and P value was considered significant at ≤0.05.

RESULTS

The sero-prevalence of HBsAg using RTK and ELISA was 19.9% and 22.4%, respectively. The prevalence of occult HBV infection was 5.2%. A total of 278 and 313 HBsAg RTK and ELISA positive samples were obtained, respectively. HBV genotype result had A (46.6%) as the most prevalent followed closely by B (44.7%), E (23.8%), D (20.9%) and C (11.2%).

CONCLUSION

HBV infection has a high prevalence among blood donors. ELISA is a more sensitive screening tool and its use should be advocated nationally. HBV genotype A is the most prevalent genotype from our study.

ABO blood groups and risk of human immunodeficiency virus infection: A systematic review and meta-analysis

The last few decades have seen a pandemic of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), which continues to cause substantial morbidity and mortality. ABO blood groups are anthropological and genetic characteristics of a population whose associations with HIV infection are still controversial. This systematic review with meta-analysis was undertaken to investigate whether certain blood groups may have associations with HIV infection. PubMed, Scopus and Web of Science databases were systematically searched as of 6 September 2021. Grey literature was identified through screening Google Scholar, and reference lists of relevant studies. All observational studies providing data on ABO blood group distribution among HIV-infected and uninfected participants were included. Using a random effect model, risk ratios (RR) and 95% confidence intervals (CIs) were pooled to quantify this relationship. Fifty eligible studies with a total of 3,068,244 participants and 6508 HIV-infected cases were included. The overall analysis found that blood group AB increased the risk of HIV infection by 19% as compared with non-AB blood groups (RR = 1.19, 95% CI: 1.03-1.39, p = 0.02). Pooled estimates for other blood groups failed to reach statistical significance. Subgroup analyses identified a positive relationship between AB blood group and HIV infection within Asia, patient populations (as opposed to blood donors and general populations), studies with lower sample sizes, high-income countries and studies with a moderate quality score. The sequential omission and re-analysis of studies within sensitivity analyses produced no change in the overall pooled effect. In conclusion, this study identified that blood group AB carriers were more susceptible to HIV infection. Future investigations should be directed toward clarification of the exact role of ABO blood groups in HIV infection and the possible underlying mechanisms.

Knowledge, attitude and seropositivity of hepatitis B virus among blood donors in the Bamenda Regional Hospital Blood Bank, Cameroon

Introduction

despite the existence of a preventive vaccine against hepatitis B viral (HBV) infection, approximately 250 million people are infected with the virus worldwide. This study aimed at evaluating the level of knowledge, attitude and seropositivity of the disease among apparently healthy, potential blood donors at the blood service of the Bamenda Regional Hospital Blood Bank.

Methods

a cross-sectional study was carried out from March to May 2019 among 250 blood donors. Following screening for hepatitis B surface antigen (HBsAg) using the one-step HBsAg test strip, information on the level of knowledge and attitude towards the infection was obtained using a self-administered questionnaire. The correlation analysis was done to assess relationships between selected factors and knowledge of hepatitis B, p-value of 0.05 was considered as statistical significance.

Results

the seropositivity of HBV was 6.4% (n = 16). Overall, 46.8% (n = 19) of the study participants had adequate knowledge while 76.3% (n = 31) had a positive attitude toward the disease. The highest seropositivity was observed in singles (7.1%; n = 13), primary school leavers (14.3%; n = 5), unskilled laborers (14.5%; n = 8) and replacement donors (9.33%; n = 7). The probability of being hepatitis B seropositive was higher in males, students (aOR: 8.8, 95% CI 0.7-96.1; p = 0.046) and those who had attained higher education (aOR: 3.2, 95% CI 0.8-12.7; p = 0.016). Independent factors responsible for higher odds of inadequate knowledge were being a male and attaining secondary education. On the contrary, students (aOR: 0.3, 95% CI 0.1-0.8; p = 0.012) and those with a history of blood donation (aOR: 0.5, 95% CI 0.2-0.9; p = 0.042) recorded lower odds of inadequate knowledge.

Conclusion

the prevalence of hepatitis B among blood donors in this blood service is in the high intermediate category. Overall, the level of knowledge on this infection among these blood donors is average. These findings suggest that health education on HBV infection should be provided to the public as a major strategy to curb the infection.

Highlighting a population-based re-emergence of Syphilis infection and assessing associated risk factors among pregnant women in Cameroon: Evidence from the 2009, 2012 and 2017 national sentinel surveillance surveys of HIV and syphilis

Background

Syphilis and HIV can be transmitted from pregnant women to their children and they remain a public health problem in Africa. Our study aimed to determine the trends of seroprevalence of HIV/syphilis co-infection and syphilis infection overtime through the national surveillance system in Cameroon and to explore associated risk factors.

Methods

We conducted cross-sectional studies of HIV and syphilis, targeting each year 7000 first antenatal care (ANC-1) attendees at the same sites during the 2009, 2012 and 2017 sentinel surveillance surveys. Pregnant women were enrolled at their ANC-1, sociodemographic and clinical information were collected. HIV and Syphilis test were performed by serial algorithm as per the national guidelines. Trends were assessed for HIV, syphilis and HIV/syphilis by estimating seroprevalence from cross-sectional studies. Associated risk factors were explored using multinomial logistic regression with 4 outcomes: HIV/syphilis co-infection, HIV infection only, syphilis infection only and no infection.

Results

Overall, 6 632, 6 521 and 6 859 pregnant women were enrolled in 2009, 2012 and 2017 respectively. In 2017, a total of 3 901 pregnant women enrolled were tested for syphilis. Almost half of them (47.9%) were living in urban area and were aged less than 25 years (44.7%). While HIV epidemic was on a decline (from 7.6% (95% CI: 6.99–8.28) in 2009 to 5.7% (95% CI: 4.93–6.4) in 2017), a huge significant increase of syphilis prevalence was observed (from 0.6% (95% CI:0.40–0.80) in 2009 to 5.7% (95% CI:4.93–6.40) in 2017). Pregnant women residing in rural areas were more likely to be infected with syphilis than those living in the urban area (aOR = 1.8 [95% CI: 1.3–2.4]). Unmarried pregnant women were three time more likely to be infected by HIV/Syphilis Co-infection than married, cohabiting, widow or divorced pregnant women (aOR = 2.8 [95% CI: 1.3–2.4]). Furthermore; living in Northern region was associated with a lower risk of being infected with HIV (aOR = 0.6 [95% CI: 0.5–0.9]) and Syphilis infection (aOR = 0.6 [95% CI: 0.4–0.9]).

Conclusion

The epidemiological dynamics of syphilis suggests a growing burden of syphilis infection in the general population of Cameroon. Our findings support the fact that while emphasizing strategies to fight HIV, huge efforts should also be made for strategies to prevent and fight syphilis infection especially among HIV positive women, in rural area, and southern regions.

Prevalence and burden of HBV co-infection among people living with HIV: A global systematic review and meta-analysis

Globally, in 2017 35 million people were living with HIV (PLHIV) and 257 million had chronic HBV infection (HBsAg positive). The extent of HIV-HBsAg co-infection is unknown. We undertook a systematic review to estimate the global burden of HBsAg co-infection in PLHIV. We searched MEDLINE, Embase and other databases for published studies (2002-2018) measuring prevalence of HBsAg among PLHIV. The review was registered with PROSPERO (#CRD42019123388). Populations were categorized by HIV-exposure category. The global burden of co-infection was estimated by applying regional co-infection prevalence estimates to UNAIDS estimates of PLHIV. We conducted a meta-analysis to estimate the odds of HBsAg among PLHIV compared to HIV-negative individuals. We identified 506 estimates (475 studies) of HIV-HBsAg co-infection prevalence from 80/195 (41.0%) countries. Globally, the prevalence of HIV-HBsAg co-infection is 7.6% (IQR 5.6%-12.1%) in PLHIV, or 2.7 million HIV-HBsAg co-infections (IQR 2.0-4.2). The greatest burden (69% of cases; 1.9 million) is in sub-Saharan Africa. Globally, there was little difference in prevalence of HIV-HBsAg co-infection by population group (approximately 6%-7%), but it was slightly higher among people who inject drugs (11.8% IQR 6.0%-16.9%). Odds of HBsAg infection were 1.4 times higher among PLHIV compared to HIV-negative individuals. There is therefore, a high global burden of HIV-HBsAg co-infection, especially in sub-Saharan Africa. Key prevention strategies include infant HBV vaccination, including a timely birth-dose. Findings also highlight the importance of targeting PLHIV, especially high-risk groups for testing, catch-up HBV vaccination and other preventative interventions. The global scale-up of antiretroviral therapy (ART) for PLHIV using a tenofovir-based ART regimen provides an opportunity to simultaneously treat those with HBV co-infection, and in pregnant women to also reduce mother-to-child transmission of HBV alongside HIV.

Decline in the seroprevalence of syphilis markers among first-time blood donors in Libreville (Gabon) between 2004 and 2016

Background

Very few studies have been conducted on the seroprevalence of syphilis in Gabon. According to the World Health Organization, the average seroprevalence of syphilis has declined from 5.5 to 1.1% in Central Africa. The aim of this study was to test the hypothesis that syphilis decreased in Gabon between 2004 and 2016 and to identify factors involved in this pattern by testing a large sample of first-time blood donors in the capital Libreville.

Methods

The detection of Treponema pallidum was done using a Rapid Plasma Reagin test (RPR) and confirmed by an ELISA test using the Biorad Syphilis Total Antibody EIA II kit or BioMerieux Trepanostika TP recombinant. Assays were performed by dedicated technicians according to manufacturers’ recommendations and following the laboratory standard operating procedures. Test results were manually transferred into the laboratory Excel files and hand-written in the laboratory logbook for syphilis testing. Logistic regression was used to assess the impact of sociodemographic characteristics on syphilis marker seroprevalence in both univariate and multivariable analysis. Odds ratios (OR) and 95% confidence intervals were calculated.

Results

The seroprevalence of syphilis markers was 8.4% (95% CI = 7.9–8.9) in 2004 and 2.4% (95% CI = 2.1–2.7) in 2016. The difference was significant [OR = 3.78; 95% CI (3.26–4.38); P < 0.001]. The decrease in syphilis seroprevalence was significant in both women and men and in each age group in univariate analysis. In multivariable analysis, controlling for all sociodemographic factors, the decrease in syphilis seroprevalence from 2004 to 2016 remained significant (OR = 3.29; 95% CI = 2.88–3.88, P < 0.001). The seroprevalence of syphilis decreased significantly in men compared to women and young donors compared to donors aged ≥36 years.

Conclusions

This study shows a significant decline in syphilis seroprevalence in first-time blood donors in Libreville, Gabon. Government actions, including multiple HIV prevention activities, are a likely part of this decline.

Prevalent hepatitis B surface antigen among first-time blood donors in Gabon

Despite chronic Hepatitis B virus (HBV) infection being the main cause of younger-onset complex liver disease including cirrhosis and hepatocellular carcinoma (HCC) in Africa, very little is known regarding the seroprevalence of HBV in the Gabonese general population. This investigation aimed to provide strong epidemiological data and risk factors associated with HBV infection in first-time blood donors representative of the urban adult population. The screening of HBsAg was carried out using 4th generation ELISA kits. The overall seroprevalence of HBsAg was 7.28%. The frequency of HBsAg was differential and marked by annual variations in blood donors from 2009 to 2016. Seroprevalence was 2-fold higher among males versus females (OR = 1.90 (95% CI: 1.75-2.06), P<0.001). HBsAg seroprevalence was significantly higher in donors of the age group 25-35 years old compared to donors of the age group <18 years (OR = 1.64 (95% CI: 1.03-2.60), P = 0.04). The seroprevalence of HBsAg in family/replacement donors (FRD) was significantly higher than that of voluntary non-remunerated donors (VNRD) (OR = 0.88 (95% CI: 0.83-0.94), P <0.001). The simultaneous comparison of HBsAg seroprevalence with blood donation type, gender and age showed that the higher prevalence in FRD was significant only in males between 18 and 45 years and in females between 25 and 34 years of age. This study confirms the high endemicity of HBV in Gabon while identifying the most infected age groups for both men and women.

Seroprevalence of hepatitis C virus infection in Cameroon: a systematic review and meta-analysis

OBJECTIVE

Better knowledge of hepatitis C virus (HCV) seroprevalence at the national level can help to implement pertinent strategies to address the HCV-related burden. The aim of this paper was to estimate the seroprevalence of HCV infection in Cameroon.

DESIGN

Systematic review and meta-analysis.

PARTICIPANTS

People residing in Cameroon.

DATA SOURCES

Electronic databases including PubMed/MEDLINE, AJOL, WHO-Afro Library, Africa Index Medicus, National Institute of Statistics and National AIDS Control Committee, Cameroon from 1 January 2000 to 15 December 2016 were searched. English and French languages papers were considered. Two independent investigators selected studies. The methodological quality of the studies was assessed using the Newcastle-Ottawa scale.

RESULTS

31 studies including 36 407 individuals were finally considered. There was no national representative study. The overall pooled prevalence was 6.5% (95% CI 4.5% to 8.8%; I²=98.3%). A sensitivity analysis of individuals at low risk of HCV infection showed a pooled prevalence of 3.6% (95% CI 2.3% to 5.2%, I²=97.7%, 18 studies) among 22 860 individuals (general population, blood donors and pregnant women), which was higher than for a high-risk population (healthcare workers and people with other identified comorbidities), 12.2% (95% CI 4.9% to 22.2%; I²=98.3%, 13 studies); p=0.018. The prevalence was higher in the East region, in rural settings, and when using an enzyme immunoassay technique for detecting HCV antibodies. Sex, sites, study period, sample size, timing of data collection and methodological quality of studies were not sources of heterogeneity.

LIMITATION

One-third of studies (29.0%) had a low risk bias in their methodology and most were facility-based (87.1%).

CONCLUSION

The seroprevalence of HCV infection in Cameroon indicates the need for comprehensive and effective strategies to interrupt HCV transmission in the Cameroonian population. Specific attention is needed for the East region of the country, rural settings and high-risk populations. A national representative study is needed to provide better estimates.

Seroprevalence of hepatitis B virus infection in Cameroon: a systematic review and meta-analysis

OBJECTIVE

Better knowledge of hepatitis B virus (HBV) infection prevalence at the national level can help to implement pertinent strategies to address HBV related burden. The aim was to estimate the seroprevalence of HBV infection in Cameroon.

DESIGN

Systematic review and meta-analysis.

PARTICIPANTS

People residing in Cameroon.

DATA SOURCES

Electronic databases including PubMed/MEDLINE, African Journals Online (AJOL), ScienceDirect, WHO-Afro Library, WHO-IRIS, African Index Medicus, National Institute of Statistics and National AIDS Control Committee, Cameroon; regardless of language and from 1 January 2000 to 30 September 2016. This was completed with a manual search of references of relevant papers. Risk of bias in methodology of studies was measured using the Newcastle-Ottawa Scale.

RESULTS

Out of 511 retrieved papers, 44 studies with a total of 105 603 individuals were finally included. The overall pooled seroprevalence was 11.2% (95% CI 9.7% to 12.8%) with high heterogeneity between studies (I²=97.9%). Egger's test showed no publication bias (p=0.167). A sensitivity analysis excluding individuals at high risk of HBV infection and after adjustment using trim and fill method showed a pooled seroprevalence of 10.6% (95% CI 8.6% to 12.6%) among 100 501 individuals (general population, blood donors and pregnant women). Sources of heterogeneity included geographical regions across country and setting (rural 13.3% vs urban 9.0%), and implementation of HBV universal immunisation (born after 9.2% vs born before 0.7%). Sex, site, timing of data collection, HBV screening tools and methodological quality of studies were not sources of heterogeneity.

LIMITATION

Only a third of the studies had low risk of bias in their methodology.

CONCLUSION

The seroprevalence of HBV infection in Cameroon is high. Effective strategies to interrupt the transmission of HBV are urgently required. Specific attention is needed for rural settings, certain regions and people born before the implementation of the HBV universal immunisation programme in Cameroon in 2005.

REGISTRATION

PROSPERO, CRD42016042654.

Hepatitis C in Cameroon: What is the progress from 2001 to 2016?

Chronic hepatitis C is a major public health problem in sub-Saharan countries and particularly in Cameroon where the prevalence rate is around 7.6% in the age group of 55-59 years. Recent investigations into this infection allowed defining a national seroprevalence, characterizing virological and biological profiles of infected patients and identifying medicinal plants of potential interest in hepatitis C therapy. However, in Cameroon, no existing report currently presents a good overview of hepatitis C research in relation to these parameters. This review seeks to discuss major findings published since 2001 that have significantly advanced our understanding of the epidemiology and treatment of hepatitis C in Cameroonian patients and highlight the major challenges that remain to overcome. We performed a systematic search in Pubmed and Google Scholar. Studies evaluating prevalence, treatment, coinfection, and genetic diversity of HCV infection in Cameroon were included. Studies suggest that HCV prevalence in Cameroon would be low (around 1.1%) with a lot of disparities according to regions and age of participants. Elders, pregnant women, blood donors, health care workers, patients on hemodialysis, and homozygous sickle cell patients have been identified as risk groups. Moreover, HCV/HBV coinfection was found more prevalent than HCV/HIV coinfection. Phylogenic studies reported circulation of three main genotypes such genotypes 1, 2, and 4 but little is known about antiviral candidates from the Cameroonian pharmacopeia. In conclusion, some epidemiological data prove that hepatitis C in Cameroon is well known but efforts are still necessary to prevent or control this infection.