Department of Microbiology, University of Yaounde I, Yaounde, Cameroon.
Mbongue-Mikangue Chris André, Department of Microbiology, University of Yaounde I, Yaounde, Cameroon.
Abstract
Background: The global burden of Hepatitis B virus (HBV) infection continues to rise; However, Sub-Saharan Africa are the most affected by it. The status of HBV in pregnant women is essential for the effective management of the disease and the prevention of mother to child transmission. This study explores, the prevalence of HBsAg and risks factors associated.
Objective: To investigate the risks factors associated with infection among pregnant women and determine the prevalence of HBsAg at the Yaounde University Teaching Hospital (YUTH).
Methodology: A cross-sectional, prospective and monocenter study was conducted from 17 September 2018 to 25 February 2019 in 102 pregnant women. After obtaining ethical clearance, obstetric and sociodemographic risk factors were collected; samples were also taken and analyzed by the immuno-chromatographic method for the detection of HBsAg. Statistical analysis was performed by Microsoft Excel Version 2016; the statistical software SPSS Version 22. A P value <0.05 was considered statistically significant.
Results: Of the 102 pregnant women, 10.78% (11/64) were positive for HBsAg; 26.47% (27/64) had previous contact with HBV. The highest prevalence of HBsAg was recorded in the age group 25-35 years (11.76%, P = 0.95). Similarly, the single status (P = 0.001) scarification (P = 0.00) and tattooing (P = 0.00008) were significantly associated with HBV infection and previous contact with HBV.
Conclusion: This study highlights the important of pregnant women and newborns. The HBV infection is high among pregnant women. It is therefore necessary to introduce routine in prenatal assessment of pregnant women routine screening for HBV markers and possibly a vaccination to prevent vertical transmission (mother to child).
Keywords: Pregnancy; HBV; Risk factors, YUTH.
Introduction
Hepatitis B is a serious global public health problem (1). Hepatitis B is an infection caused by the hepatotropic virus (2). Hepatitis B Virus (HBV) is an oncogenic virus: its specific virological characteristics and the natural history of infection contribute to the development of liver fibrosis, Hepatocellular Carcinoma (HCC). In particular, a prolonged duration of infection and a high viral load, which is more frequent among patients infected in childhood, favor chronicity and carcinogenesis (3). The impact of chronic liver disease is significant worldwide, as liver cancer is the third most common cause of cancer deaths (4). The prevalence of hepatitis B varies from region to region (5). A systematic review by Mahamat et al (2021) estimates that the prevalence of Hepatitis B in Cameroon is low, with overall 2.3 % all ages (6). In 2015, the World Human Organization (WHO) estimated that 257 million people were living with chronic hepatitis B, including 65 million women of childbearing age, with an estimated number of deaths of 887000, mainly due to HCC(7). HBV and/or hepatitis C virus (HCV) coinfection in people living HIV (PLHIV) receives considerable public health attention due to its high burden and its negative impact on the survival of affected patients. It primarily occurs in immunocompromised patients or pregnant women (8). Mother-to-child transmission (MTCT) is one of the main routes of HBV transmission worldwide, despite the proven effectiveness of immunoprophylaxis, in particular birth dose of HBV vaccine. Cameroon is also a country of high endemic, with a significant distribution in rural (13.3%) and urban areas (10.7%)(9). MTCT is an important route of HBV transmission (10). It can occur in three distinct ways, namely during pregnancy, during delivery and during breastfeeding (11). Vertical transmission is common among asymptomatic female carries who are unaware of their carrier status. In cases of high viral multiplication in the mother and in the absence of serovaccination, 90 % infected newborns are likely to develop chronic hepatitis B (12) and have a much higher risk of developing liver disease, including HCC in adulthood (13). MTCT of HBV is responsible for more than a third of chronic viral hepatitis cases(14).In 2016, Cameroon implemented the” test and treat” policy(15). Overall, there is a paucity of research specifically addressing pregnant women and the risks of MTCT, particularly in low-and middle-income countries (LMICs) like Cameroon. The study aims were to estimate the prevalence of hepatitis B surface antigen (HBVsAg) and identify the risk factors associated among pregnant women in Yaounde.
Materials and Methods
Study design and setting: A prospective and cross-sectional study was conducted from September 17, 2018 to February 25,2019 within the gynecology department of Yaounde University Teaching Hospital (YUTH). The participants were pregnant women who came for consultation in the Gynecology and Obstetrics Department of the YUTH.
The sample size was obtained using the following formula:
α= 0,05 → Z1-α= 1,96 d’après la loi normale; P: Prévalence de sujets présentant la variable étudiée; Z1-a : erreur d’échantillonnage constante; i : erreur opérationnelle ou marge d’erreur (16)
Study population and eligibility: This study focused on pregnant women who were visited the Gynaecology and Obstetrics Departments of the health facilities mentioned above. Inclusion criteria were women who had antenatal care follow-up with prenatal consultation and who gave informed consent.
Sampling procedure: Based on the expected annual population of pregnant women in the Gynaecology and Obstetrics Department of Yaounde University Teaching Hospital (YUTH). Participants were recruited consecutively as they presented for antenatal care at the selected health facilities, during the study period. The sample was therefore distributed among the following maternities: YUTH, Gynaecology and Obstetrics Department (102 pregnant women).
Data collection method: A structured questionnaire was used to collect data. The questionnaire was divided into two parts: sociodemographic characteristics (age, employment status, marital status, type of marriage) and risk behaviours (blood transfusion, history of surgery, history of hospitalization, HBsAg+ mother, family history of HBV infection, history of transcutaneous procedure like acupuncture, genital mutilation, scarification, drug use, history of HBV testing, prison stay and unprotected sex).
Sample collection: After obtaining informed consent and completing the questionnaire, a 5 ml blood sample was drawn. Blood samples
were given a unique identification number and centrifuged at 3000 rpm for 15 minutes. Sera were aliquoted into two parts, one for serology and one for molecular analysis. Both aliquots were frozen at -20°C in the biobank laboratory of the YUTH after sent to the Hematology Department/Blood Bank of the YUTH(17).
Laboratory procedure:
Serological tests: We used two rapid HBV diagnostic test from (Abbott Laboratories, Abbott Park, Illinois, USA). All tests were carried out following the manufacturer’s guidelines.
Data analysis: Data were entered into an Excel database and analyzed using Statistical Package for Social Sciences (SPSS) version 22 software. Descriptive analysis and logistic regression were used to examine the association between dependent variables, sociodemographic characteristics and risk factors. Quantitative variables were expressed as mean ± standard deviation, and categorical variables were expressed as numbers (percentages). An independent t-test was used to compare the means of continuous variables. When normal distribution or equality of variance could not be assumed, the Mann-Whitney U test was used. The chi-squared test was used to compare proportions. In both cases, the significance level was set at p < 5%.
Ethics Committee: The research protocol received administrative authorization from the Directorate of the Yaounde University Teaching Hospital, Reference N°245/AR/CHUY/DR/DGA/WAPRC. The standard measures necessary to guarantee the confidentiality of the information collected in the files have been taken. Only participant file numbers were recorded and access to the data was secured by an encrypted password.
Results
Sociodemographic characteristics: A total of 102 pregnant women were recruited in the study with a mean age was 24.11±5.58 years, and more than half of the pregnant women (51.09%) were aged between 21 and 30 years. 94 (92.16%) were married. Several occupations were represented, the majority being housewives (85, 83.33%), followed by students (8, 7.85%). Regarding their HBV serology, (102, 100 %) of the pregnant women did not know their status beforehand (Table 1).
Prevalence of HBsAg among pregnant women: Thirty-three (11) of the 102 pregnant women were positive for HBsAg (HBsAg+), giving an prevalence of 10.78% (95% CI 3.19- 18.37). Table 2
Factors associated with HBV infection among pregnant women: Results presented in Table 2 show that the prevalence of HBV infection was 16% in women with a history of HBV testing versus 4.2% in women without a history of HBV testing (P˂0.001) (Table 3). In the univariate regression analysis, the following parameters: age, blood transfusion, occupational status, genital mutilation, scarring, HBsAg+ mother, prison stay, history of HBV testing and history of hospital admission were identified as candidate variables for multivariate analysis. Multivariate regression showed that having an HBsAg positive mother (AOR: 20.70, 95%CI:3.63-117.05, P=0.001) and a history of HBV testing (AOR: 4.33, 95%CI:1.81-10.56, P=0.001) were the risk factors associated with HBsAg positivity (Table 1).
Table 1: Distribution of the study population according to so-ciodemographic characteristics
Table 2: Carriage rate of markers of hepatitis B virus infection
Discussion
In the present study, the findings highlight that the seroprevalence of HBV infection in pregnant women was 10.78 %. According to the WHO classification, this prevalence might be considered as an high rate (≥ 8% ) (18). The prevalence of HBsAg found in our study is higher than that reported among pregnant women in eight health facilities in the city of N'Djamena (Chad) (7.2 %) (19). This difference could be due to the characteristics of the study population. Women living in urban areas are likely to have fewer risk factors than those living in rural areas, because they might have a higher level of education. It suggests that rural areas should also be the targeted in future studies and should benefit also from HBV awareness, screening. Our results are comparable to recent studies in pregnant women in the Wolaita zone of southern Ethiopia (7.3%) (20). In contrast, HBV seroprevalence in our study is lower than that reported in Northern Cameroon (20%) (21), regions of political-military instability and weakened health systems. On the other hand, HBV seroprevalence in our study is higher than that reported in studies conducted in Eritrea (22), and Egypt (23) (3.2% and 5% respectively). These differences may be explained by local/national strategies to prevent (24). In our study, 100 % of participants did not know their HBV status. In contrast, the data reported by Gebreerkos in Ethiopia, who reported that 85.87% of pregnant women had never been screened for HBV (25). The lack of financial resources and of national prevention strategies, together with a lack of knowledge about hepatitis B prevention and treatment among health professionals involved in the care of pregnant women may explain these results. While routine screening for hepatitis B is an important means of preventing mother-to-child transmission of HBV, precocious detection of infection in women would also encourage vaccination of family members. Actually, there is no policy for routine HBsAg testing of pregnant women unless they pay for it. Thus, there is a need to introduce a policy of systematic and free screening of pregnant women, at the antenatal visit, with follow-up in case of HBsAg positivity. We also found that prior screening was independently associated with hepatitis B surface antigen carriage (p=0.001). Sixteen per cent of the pre-screened participants tested positive. A similar result was reported by Halatoko in Togo, who reported a statistical association between knowledge of HBV status and hepatitis infection (p<0.001) [26]. This means that pregnant women were informed during the antenatal consultation of their previous HBV status and may have asked for confirmation. However, in Cameroon, after screening, no further tests (HBeAg, viral load) are performed. Pregnant women with financial means may be able to buy the vaccine for their baby if they are informed. In addition, in the case of HBsAg positivity, they will not be referred to a hepatologist, and will not have an assessment of their liver disease, i.e. liver tests, and, nor of appropriate monitoring and treatment. The present work shows numerous limitations, namely the cross-sectional type of the study, however, did not allow conclusions to be drawn on the causal links with the associated factors identified. The hepatitis B viral load was not carried out in our patients. The small sample size which does not allow the results of this work to be generalized. And short duration of the study do not provide sufficient statistical power to generalize the results of this study to all pregnant women at the Yaoundé University Hospital. The seroprevalence obtained without using molecular techniques. The small number of risk factors considered in this work. However, the present work showed strengths such as highlighting the prevalence of HBsAg in pregnant women.
Conclusions
This study provides valuable insight into factors risks associated in occurring HBV infection and the prevalence of HBs-Ag. In the present study, our results show that HBV seroprevalence (10.78%) is in the high range according to the WHO classification. It is also needed to build the capacity of health workers to assess and manage people with hepatitis B, vaccinating newborns, monitoring (including HBV valence) and treating the mother if possible. This effectively demonstrates the circulation of this pathogen in Yaoundé.
Acknowledgments: We sincerely thank the Yaounde University Teaching Hospital which permits us to recruit patients, the author would like to acknowledge all the participants who contributed to this research. The authors would also like to acknowledge the staff of the Yaoundé University Teaching Hospital, Cameroon
Author Contributions
Mbongué-Mikangué.C. André designed and set up the research project, collected the samples with Riwom Essama Sara H. led the technical aspects at the Hematology Department/Blood Bank of the YUTH. The analysis of the data and the writing of this article saw the collaboration of all authors.
Funding: No funding was obtained for this study.
Data Availability Statement: The data supporting the results of this study are available on request from the corresponding author. The data is not publicly available because it contains information that could compromise the confidentiality of research participants.
Conflicts of Interest: The authors declare that they have no conflict of interest.
