Toward the elimination of hepatitis B: networking to promote the prevention of vertical transmission of hepatitis B virus through population-based interventions and multidisciplinary groups in Africa.

The WHO African Region had 81 million people with chronic hepatitis B in 2019, which remains a silent killer. Hepatitis B virus (HBV), hepatitis delta virus (HDV), and HIV can be transmitted from the mother to child. If the HBV infection is acquired at infancy, it may lead to chronic hepatitis B in 90% of the cases. WHO reports that 6.4 million children under 5 years live with chronic hepatitis B infection worldwide. The prevention of mother-to-child transmission (PMTCT) of HBV is therefore critical in the global elimination strategy of viral hepatitis as we take lessons from PMTCT of HIV programs in Africa. We sought to create a network of multidisciplinary professional and civil society volunteers with the vision to promote cost-effective, country-driven initiatives to prevent the MTCT of HBV in Africa. In 2018, the Mother-Infant Cohort Hepatitis B Network (MICHep B Network) with members from Cameroon, Zimbabwe, and the United Kingdom and later from Chad, Gabon, and Central African Republic was created. The long-term objectives of the network are to organize capacity-building and networking workshops, create awareness among pregnant women, their partners, and the community, promote the operational research on MTCT of HBV, and extend the network activities to other African countries. The Network organized in Cameroon, two "Knowledge, Attitude and Practice" (KAP) surveys, one in-depth interview of 45 health care workers which revealed a high acceptability of the hepatitis B vaccine by families, two in-person workshops in 2018 and 2019, and one virtual in 2021 with over 190 participants, as well as two workshops on grant writing, bioethics, and biostatistics of 30 postgraduate students. Two HBV seroprevalence studies in pregnant women were conducted in Cameroon and Zimbabwe, in which a prevalence of 5.8% and 2.7%, respectively, was reported. The results and recommendations from the MICHep B Network activities could be implemented in countries of the MICHep B Network and beyond, with the goal of providing free birth dose vaccine against hepatitis B in Africa.

Seroprevalence of hepatitis B and associated factors among inmates: a cross sectional study in the Douala New Bell Prison, Cameroon.

INTRODUCTION: in Cameroon, data on viral hepatitis B infection in prison environments is limited. We determined the prevalence of hepatitis B infection (HBV) and correlates among prisoners incarcerated at the Douala New Bell Central Prison in Cameroon. METHODS: this was a cross-sectional study carried out in July 2018 and included 940 randomly selected prisoners. Data were collected using pre-tested questionnaire while blood screening for HBV surface antigen (HBs Ag) used rapid test, with confirmation via Elisa test. Sociodemographic characteristics and risk factors were compared among the three age groups with respect to the prison's partitioning. Factors associated with positive HBs Ag were identified using logistic regression adjusted to age and gender. Confounders were then excluded by logistic multivariate analysis. All p values less than 0.05 were considered statistically significant. RESULTS: of the 940 prisoners selected, 94% were male. The mean age of the study population was 33.81 ± 10.35 years. The median duration of incarceration and median number of incarcerations were 12 months (IQR: 5-36) and 1 (IQR: 1-2) respectively. HBV prevalence was 12.9% (95% CI: 10.7-15%). The use of non-injectable illicit drugs (OR: 3.5; 95% CI: 1.9-6.2; P<0.001), sharing of needle or razors (aOR: 24.1; 95% CI: 12.9-45.0; P<0.001), sharing of tooth brushes(aOR: 2.7; 95% CI: 0.9-7.4) (P=0.053), having tattoos or piercings (aOR: 1.9; 95% CI: 1.1-3.1; P=0.01) were significantly associated with HBs Ag seropositivity. CONCLUSION: prisoners in this setting had a high prevalence of HBV and related risk factors. These findings highlight an urgent need to implement control strategies and programs that reach people in detention centers in Cameroon.

Regional vulnerability for COVID-19 in Cameroon.

INTRODUCTION: few studies have assessed risk for coronavirus disease 2019 (COVID-19) within African countries. Here we examine differences in vulnerability to COVID-19 among the ten administrative regions and two major cities of Cameroon based on epidemiological risk factors and access to healthcare resources. METHODS: regional epidemiological and healthcare access vulnerability indices were created and compared with cumulative COVID-19 cases, case fatality rates, co-morbidities, and healthcare resources in Cameroon. RESULTS: based on epidemiological risk factors, populations in the East Region, Douala (in the Littoral Region), West Region, and Yaoundé (in the Center Region) are at highest risk for COVID-19. Meanwhile, the North, Far North, East, and Adamawa Regions had the most healthcare access vulnerability. COVID-19 cases per population were highest in the Center, Littoral, and East Regions. Case fatality rates were greatest in the North Region. Potential co-morbidities with greater prevalence among COVID-19 patients included male sex, hypertension, and diabetes. CONCLUSION: epidemiological risk factors for COVID-19 and access to healthcare varies between the regions of Cameroon. These discrepancies are potentially reflected in regional differences of COVID-19 cases and case fatality rates. In particular, the East Region has high epidemiological risk factors and low healthcare accessibility compared to other regions. Understanding the relationships between epidemiological risk factors, access to healthcare resources, and COVID-19 cases in Cameroon could aid decision-making among national policymakers and inform further research.

Human immunodeficiency virus type 1 ((HIV-1) subtypes in the northwest region, Cameroon.

BACKGROUND: The high genetic diversity of HIV-1 has been shown to influence the global distribution, disease progression, treatment success, and the development of an effective vaccine. Despite the low HIV prevalence in Cameroon, all the major HIV subtypes alongside several circulating recombinant forms (CRFs) and unique recombinant forms (URFs) have been reported in Cameroon. To date, HIV-1 diversity in some parts of Cameroon has been largely studied however, information on circulating HIV-1 subtypes in the Northwest region (NWR) of Cameroon is dearth. Therefore the aim of this study was to determine the current circulating HIV-1 subtypes among adults in the NWR of Cameroon. METHODS: The genetic analysis of the reverse transcriptase region of the pol gene was performed on 81 samples. The samples were collected from drug naïve patients aged between 18 and 61 years residing within the rural and urban towns in the NWR during the period between February and April 2016. Viral RNA was extracted from plasma, reverse-transcribed, further amplified by nested-PCR before sequencing using an in-house protocol. Generated sequences were then phylogenetically analyzed together with references using MEGA 7. RESULTS: Phylogenetic analysis revealed a broad viral diversity including CRF02 _AG (74.1%), F2 (7.4%), D (7.4%), G (3.7%), A1 (1.2%), CRF22_01A1 (2.5%), CRF06_cpx (1.2%), CRF09_cpx (1.2%), CRF11_cpx (1.2%). Three close epidemic clusters were found among F2 (1) and CRF02_AG (2) variants. For the first time we are reporting the CRF22_01A1 subtype in this region. CONCLUSION: Our findings update HIV-1 subtypes information in Cameroon and uphold previous studies that CRF02_AG is the most prevalent subtype. This CRF02_AG subtype may have important public health, research, and clinical consequences.

Implementation of HIV early infant diagnosis and HIV type 1 RNA viral load determination on dried blood spots in Cameroon: challenges and propositions.

The testing of dried blood spots (DBSs) for human immunodeficiency type 1 (HIV-1) proviral DNA by PCR is a technology that has proven to be particularly valuable in diagnosing exposed infants. We implemented this technology for HIV-1 early infant diagnosis (EID) and HIV-1 RNA viral load determination in infants born of HIV-1-seropositive mothers from remote areas in Cameroon. The samples were collected between December 2007 and September 2010. Fourteen thousand seven hundred and sixty-three (14,763) DBS samples from infants born of HIV-positive mothers in 108 sites nationwide were tested for HIV. Of these, 1452 were positive on first PCR analyses (PCR1), giving an overall infection rate of 12.30%. We received only 475 DBS specimen for a second PCR testing (PCR2); out of these, 145 were positive. The median HIV-1 RNA viral load for 169 infant DBS samples tested was 6.85 log copies/ml, with values ranging from 3.37 to 8 log copies/ml. The determination of the viral load on the same DBS as that used for PCR1 allowed us to bypass the PCR2. The viral load values were high and tend to decrease with age but with a weak slope. The high values of viral load among these infants call for early and effective administration of antiretroviral therapy (ART). The findings from this study indicate that the use of DBS provides a powerful tool for perinatal screening programs, improvement on the testing algorithm, and follow-up during treatment, and thus should be scaled up to the entire nation.

Seroprevalence of human T cell leukemia virus in HIV antibody-negative populations in rural Cameroon.

Seven hundred forty-seven serum samples collected from humans in 4 separate rural village areas in Cameroon were examined for antibody to human T cell leukemia viruses (HTLVs) by use of an enzyme immunoassay followed by a Western blot assay. Of the 88 serum samples that the enzyme immunoassay found to be repeatedly reactive, the HTLV status of 49 samples was confirmed by Western blot assay to be HTLV type I, and the status of 6 samples was confirmed to be HTLV type II.