Prevalence of Hepatitis B Virus Infection among Pregnant Women Attending Antenatal Clinics in Vientiane, Laos, 2008-2014

Residual risk of mother-to-child transmission of HBV despite timely Hepatitis B vaccination: a major challenge to eliminate hepatitis B infection in Cambodia

BACKGROUND

In countries with intermediate or high hepatitis B virus (HBV) endemicity, mother-to-child transmission (MTCT) represents the main route of chronic HBV infection. There is a paucity of information on HBV MTCT in Cambodia. This study aimed to investigate the prevalence of HBV infection among pregnant women and its MTCT rate in Siem Reap, Cambodia.

METHODS

This longitudinal study included two parts, study-1 to screen HBsAg among pregnant women and study-2 to follow up babies of all HBsAg-positive and one-fourth of HBsAg-negative mothers at their delivery and six-month post-partum. Serum or dried blood spot (DBS) samples were collected to examine HBV sero-markers by chemiluminescent enzyme immunoassay (CLEIA), and molecular analyses were performed on HBsAg-positive samples. Structured questionnaires and medical records were used to examine the risk factors for HBV infection. MTCT rate was calculated by HBsAg positivity of 6-month-old babies born to HBsAg-positive mothers and ascertained by the homology of HBV genomes in mother-child pair at 6-month-old.

RESULTS

A total of 1,565 pregnant women were screened, and HBsAg prevalence was 4.28% (67/1565). HBeAg positivity was 41.8% and was significantly associated with high viral load (p < 0.0001). Excluding subjects who dropped out due to restrictions during COVID-19, one out of 35 babies born to HBsAg-positive mothers tested positive for HBsAg at 6 months of age, despite receiving timely HepB birth dose and HBIG, followed by 3 doses of HepB vaccine. Hence the MTCT rate was 2.86%. The mother of the infected baby was positive for HBeAg and had a high HBV viral load (1.2 × 109 copies/mL). HBV genome analysis showed 100% homology between the mother and the child.

CONCLUSIONS

Our findings illustrate the intermediate endemicity of HBV infection among pregnant women in Siem Reap, Cambodia. Despite full HepB vaccination, a residual risk of HBV MTCT was observed. This finding supports the recently updated guidelines for the prevention of HBV MTCT in 2021, which integrated screening and antiviral prophylaxis for pregnant women at risk of HBV MTCT. Furthermore, we strongly recommend the urgent implementation of these guidelines nationwide to effectively combat HBV in Cambodia.

Prevalence of hepatitis B and C virus infections in Lao People's Democratic Republic: The first national population-based cross-sectional survey

Population-based seroprevalence of chronic hepatitis B and C infections has not been examined in Lao People's Democratic Republic (PDR). Therefore, this study aimed to estimate the seroprevalence of these infections in the general population of Lao PDR and perform subgroup analysis. A nationwide seroprevalence survey was conducted in Lao PDR in June 2019 using the multistage cluster sampling method. Dried blood spot samples were collected onto WhatmanTM 903 filter paper by finger prick. A chemiluminescent microparticle immunoassay was used to measure the levels of hepatitis B surface antigen (HBsAg) and hepatitis C antibody (HCV-Ab). Samples in which the HBsAg level was above 0.05 IU/ml and HCV-Ab was above the signal/cutoff ratio of 1.0 were considered positive based on comparisons with the relative light unit value of a calibration sample. A total of 1,927 samples (male: 47.3%, mean age: 23.0 years) were included in the analysis. The prevalence was estimated to be 4.2% (95% confidence interval [CI]: 2.7-6.3) for HBsAg and 1.6% (95% CI: 0.5-5.3) for HCV-Ab. Multivariable analysis revealed that those aged 20-24 years (adjusted odds ratio (AOR): 2.3, 95% CI: 1.1-4.6), those aged 25-29 years (AOR: 2.7, 95% CI: 1.3-5.6), those from the Northern region (AOR: 2.8, 95% CI: 1.2-6.6), and those who were Khmu (AOR: 3.6, 95% CI: 2.0-6.8) or Hmong (AOR: 5.0, 95% CI: 3.3-7.5) were significantly more likely to be positive for HBsAg. Although there were no statistically significant differences in the HCV-Ab prevalence according to each variable, males (2.9%, 95% CI: 0.7-10.7), those aged ≥40 years (6.1%, 95% CI: 2.1-16.8), and those from the Southern region (3.3%, 95% CI: 0.6-15.3) tended to have a higher prevalence. This novel population-based survey found differences in the prevalence of chronic hepatitis B and hepatitis C virus infections in Lao PDR according to sex, age group, region, and ethnicity; however, the results of this study should be confirmed in future studies, and relevant responses tailored for each target also need to be determined to control the transmission of hepatitis B and C infections.

Sero-prevalence and associated factors of hepatitis B virus among pregnant women in Hawassa city public hospitals, Southern Ethiopia: Cross-sectional study design

Objective

This study aimed to determine the prevalence and identify associated factors of hepatitis B virus infection among pregnant women attending antenatal care (ANC) follow-up.

Methods

An institution-based cross-sectional study was conducted from March 04 to April 03, 2020. A total of 381 women were selected using systematic random sampling after every two consecutive women. Structured and interviewer administered questionnaire was used to collect the data. A 2 ml of venous blood sample was drawn from each participant. The plasma was separated from the collected blood samples and was analyzed using a rapid hepatitis B surface antigen (HBsAg) kit to determine hepatitis sero status. Data were entered into the EPI-Data version 3.1, then exported to the statistical package for social sciences version 25 software and analyzed. Multivariable logistic regression was performed to identify independent predictors of HBsAg B seroprevalence at a p-value <0.05.

Results

The prevalence of HBsAg sero-positivity among pregnant women was 6.6%, 95% CI (4.2, 8.9). History of hosptal admission (adjusted odds ratio (AOR) = 4.11; 95% CI = 1.33-12.71), surgical history (AOR = 6.8; 95% CI = 1.93-23.93), history dental procedures (AOR = 4.93; 95% CI = 1.31-18.53), and body tatoo practices (AOR = 6.822; 95% CI = 1.89-24.69) were found to be associated with HBsAg sero-positivity.

Conclusion

This study found that HBsAg sero positivity among pregnant women in the study area was in intermediate edemicity. Factors such as history of hospital admission, history of surgery, history of dental procedures, and body tattoo practices were found to be associated with HBsAg sero-positivity. The government of Ethiopia should strengthen screening of all pregnant women for HBV as a part of routine ANC in ANC clinics and treating if they are positive to prevent mother to child transmission.

Asian Pacific association for the study of liver (APASL) guidelines: hepatitis B virus in pregnancy

Hepatitis B virus (HBV) infection still remains a major public health issue in the Asia-Pacific region. Most of the burden of HBV-related disease results from infections acquired in infancy through perinatal or early childhood exposure to HBV in Asia-Pacific. Hepatitis B during pregnancy presents unique management issues for both the mother and fetus. These APASL guidelines provide a comprehensive review and recommendations based on available evidence in the literature, for the management of females with HBV infection through every stage of pregnancy and postpartum. These also address the concerns, management challenges, and required follow-up of children born to hepatitis B-positive mothers.

Prevalence of Hepatitis B Virus Infection and Factors Associated with Hepatitis B Virus Infection Among Pregnant Women Presented to Antenatal Care Clinics at Adigrat General Hospital in Northern Ethiopia

Background

Hepatitis B infection is among the most common public health concerns globally, particularly in low- and middle-income countries. The prevalence of hepatitis B infection is more common among most vulnerable populations, including pregnant women. However, there are limited studies on hepatitis B virus infection among pregnant women in low-income countries, including Ethiopia, and the previous studies focused on the general population rather than the pregnant women. The purpose of this study was to estimate the prevalence and examine factors associated with hepatitis B virus infection among pregnant women in the Northern Ethiopia.

Methods

nstitution-based cross-sectional study design and a structured face-to-face interview were used to collect data from the study participants. Simple random sampling method was used to select eligible study participants. Data were entered using EpiData version 3.1, and SPSS version 20 was used for the data analysis. We analyzed the data to examine factors associated with hepatitis B virus infection using binary and multivariable logistic regression models.

Results

The overall prevalence of hepatitis B virus infection among the study participants was 9.2%. The majority (46.7%) of the study participants infected by hepatitis B were in the age group 25-34 years. The study found that married study participants were more likely to be infected by hepatitis B when compared to the unmarried study participants. Having history of abortion [OR = 0.12 (95% CI: 0.03, 0.47), P < 0.01] and having history of tattooing [OR = 0.21 (95% CI: 0.07, 0.62), P < 0.01] were found to be statistically significantly associated with the prevalence of hepatitis B virus infection among pregnant women.

Conclusion

A significant number of pregnant women participating in the study were infected by the hepatitis B virus which needs efficient intervention to reduce the infection rate. Further, educational status, having history of surgery, dental procedure, ear piercing, abortion and tattooing were found statistically to be significant before controlling for confounders. But, after controlling for confounders, only having history of tattooing and having history of abortion were found to be independent factors affecting the prevalence of the infection.

Prevalence of Hepatitis B Virus Among Pregnant Women on Antenatal Care Follow-Up at Mizan-Tepi University Teaching Hospital and Mizan Health Center, Southwest Ethiopia

Background

Hepatitis B virus(HBV) infection is a global public health problem, even though its prevalence is disproportionately high in low- and middle-income countries. Mother-to-child transmission is a major route of HBV transmission in endemic areas. This study aimed to assess the prevalence of HBV and its determinants among pregnant women attending antenatal care at Mizan-Tepi University Teaching Hospital and Mizan Health Center, Southwest Ethiopia.

Methods

A cross-sectional study was conducted between January 13th 2020 and February 5th 2020 among 370 pregnant women. The sample size was proportionally allocated to each health institution according to the total pregnant women on antenatal care at the respective health institution and a consecutive sampling technique was used to select study participants. Serum hepatitis B surface antigen (HBsAg) was tested using a rapid diagnostic test. Data were analyzed using Statistical Package for Social Sciences (SPSS) software version 22. Multiple logistic regression analysis was done to identify the independent predictors of HBsAg serostatus at p-value <0.05.

Results

Three hundred seventy of the total 375 pregnant women participated in the study resulting in a response rate of 98.7%. Twenty-two (5.9%) of the pregnant women screened were found positive for HBsAg (prevalence=5.9%; 95% CI: 3.9–8.80%). History of contact with jaundice patients (AOR=9.87; 95% CI: 2.98–32.65), sharing sharp materials (AOR=3.96; 95% CI: 1.23–11.08) and history of multiple sexual partners (AOR=6.77; 95% CI: 2.44–18.78) were significantly associated with Hepatitis B Virus infection.

Conclusion

The endemicity of hepatitis B virus seroprevalence is intermediate in the study settings. Factors associated with hepatitis B virus serostatus were behavioral; hence, modification of these factors may help to prevent the infection.

Seroprotection at Different Levels of the Healthcare System After Routine Vaccination With Diphtheria-Tetanus-Pertussis whole cell-Hepatitis B-Haemophilus influenzae Type B in Lao People's Democratic Republic

Background

The Lao People’s Democratic Republic continues to sustain a considerable burden of vaccine-preventable diseases because of incomplete vaccine coverage and weak vaccine responses. We have assessed seroconversion after routine vaccination with the pentavalent vaccine to capture weaknesses of vaccine management at the different levels of the healthcare system.

Methods

A total of 1151 children (aged 8–28 months) with 3 documented doses of the pentavalent vaccine delivered at central hospitals in Vientiane and the provincial hospital, 3 district hospitals, and 10 health centers in Bolikhamxay province were enrolled. Sociodemographic information was collected with a standardized questionnaire. Serum samples were analyzed for antibodies against vaccine components, and bivariate and multivariable analyses were performed to identify risk factors for low vaccine responses.

Results

Seroprotection rates at the provincial, district, and health center level were as high as in central hospitals, but seroprotection rates in areas covered by remote health centers were significantly lower. Protective levels also rapidly decreased with age at sampling. Seroprotection rates in Bolikhamxay against the different components reached 70%–77% and were up to 20% higher than in previous studies in the same region; 18.8% more children received the hepatitis B vaccine birth dose and the hepatitis B virus infection rate was 4 times lower.

Conclusions

Vaccine immunogenicity has dramatically improved in a central province, likely due to training and investment in the cold chain. Nevertheless, there remains a need to focus on the “last mile” in remote areas were most children are vaccinated through outreach activities.

Prevalence of hepatitis B virus infection among pregnant women in Jos, Nigeria

Objectives:

The study sought to determine the prevalence and risk factors associated with Hepatitis B surface antigenemia (HBsAg) positivity among pregnant women in Jos, Nigeria.

Methodology:

This was a cross-sectional study carried out among the pregnant population in five healthcare facilities in Jos, between November 1, 2017 and April 30, 2018. Informed consent was obtained, and data on sociodemographic and risk factors for hepatitis B virus (HBV) infection were collected. Hepatitis B viral infection was assessed using the in vitro HBsAg diagnostic rapid kit (Acon Laboratories, USA). Descriptive statistics, Chi-square test, and logistic regression were performed to identify predictors of HBV infection in the study population. All statistical analyses were carried out on STATA version 15.

Results:

Of the 3,238 women enrolled, 7.4% (241/3238) (95% confidence interval [CI] = 6.6% to 8.4%) were HBsAg positive. The absence of HBV vaccination (adjusted odds ratio [AOR] = 2.49; 95% CI = 1.49–4.09; P < 0.001), co-infection with HIV (AOR = 1.90; 95% CI = 1.18–3.08; P = 0.009), and higher parity (AOR = 1.37; 95% CI = 1.04–1.79; P = 0.024) were independently associated with HBV infection in pregnancy.

Conclusions:

The prevalence of HBV infection among pregnant women was high, especially among those without prior vaccination for HBV, those with HIV co-infection and higher parity.

Hepatitis B Infection and Mother-to-Child Transmission in Haiphong, Vietnam: A Cohort Study with Implications for Interventions

Background

There is little data available on HBV infection and mother-to-child transmission (MTCT) in Vietnam.

Objective

This study is aimed at assessing the prevalence of HBV infection and the current situation of MTCT in Haiphong, Vietnam.

Methods

A transversal survey of 1721 pregnant women followed by an observational prospective cohort study of 183 HBV-infected women was conducted at Haiphong Gyneco-Obstetric Hospital. Women were followed up up to 12-month postpartum; use of prevention measures and the MTCT rate were evaluated. HBV infection in children was defined by a HBsAg-positive test at 12 months of age.

Results

At baseline, 183 of 1721 pregnant women (10.6%) tested HBsAg positive. Among them, 23.0% were HBeAg positive, 26.2% had a detectable load of HBV DNA, and 13.1% had a HBV DNA load ≥ 200,000 IU/mL. All women underwent MTCT prevention antiviral therapy. At delivery, 98.9% of newborns receive a HBV vaccine birth dose, and 82% received HBIG. At 12 months of age, 94.7% have received the scheduled HBV vaccines. Eight percent of infants born from followed-up women were HBsAg positive. The mother's HBeAg-positive status was associated with a higher risk of HBV infection in infants.

Conclusion

The HBV prevalence and MTCT rates are high in Haiphong. A strong national plan to increase the access to preventive measures and to monitor results is needed in order to decrease this prevalence.

Perinatal hepatitis B virus transmission in Lao PDR: A prospective cohort study

Background

Mother-to-child transmission of hepatitis B virus (HBV) is the main cause of new infections worldwide. We aimed at assessing the percentage of infants successfully immunized in two major hospitals in Vientiane, Lao PDR where HB immune globulin (HBIg) is not available.

Methods

We studied a prospective cohort of chronically HBV infected pregnant women and their infants until 6 months post-partum from January 2015 to March 2017. All infants received HB vaccine at birth and 6, 10 and 14 weeks thereafter, and HBV status was assessed at 6 months of age. HBV surface gene sequencing was performed in infected mother-infant pairs.

Results

Of 153 mothers with HB surface antigen (HBsAg), 60 (39%) had detectable serum HBe antigen (HBeAg). HBeAg positive pregnant women were younger than those negative (median age 26 versus 28 years; p = 0.02) and had a significantly higher HBV viral load at delivery (median 8.0 versus 4.0 log₁₀ IU/mL, p <0.001). Among the 120 infants assessed at 6 months of age, 5 (4%) were positive for HBsAg and had detectable HBV viral load by polymerase chain reaction. All were born to mothers with HBeAg and viral load >8.5 log₁₀ IU/mL. However, only four (3.3%, 95% CI 0.5% to 7.0%) had a virus strain closely related to their mother’s strain. HBV surface gene mutations were detected in 4 of the 5 infected infants. Anti-HBs antibody levels were below 10 IU/L in 10 (9%) uninfected infants at 6 months of age.

Conclusions

Mother-to-child transmission occurred less frequently than expected without the use of HBIg. Adding HBIg and/or maternal antiviral prophylaxis may have prevented some of these infections. The observation of unsatisfactory levels of anti-HBs antibodies in 9% of the uninfected infants at 6 months highlights the need for improvement of the universal immunization procedures.

The prevalence of HBsAg, knowledge and practice of hepatitis B prevention among pregnant women in the Limbe and Muyuka Health Districts of the South West region of Cameroon: a three-year retrospective study

Introduction

hepatitis B infection is caused by the hepatitis B virus (HBV). HBV is transmitted through sexual intercourse, by exchange of saliva during kissing and also to newborns of infected mothers. In the Global Burden of Diseases 2010, 786,000 deaths were attributed to HBV. Studies in Cameroon, reported the prevalence of HBV as high as 10.1% and 12% among blood donors in hospital blood banks. This study therefore, aims at determining the prevalence of HBsAg, knowledge and practices of pregnant women on HBV prevention and transmission in the Limbe Health District (LHD) and Muyuka Health District (MHD).

Methods

ANC registers were exploited from the health centers for a period of three years (2014-2016) in order to determine the prevalence of HBV infection. 270 women attending ANC were selected by exhaustive sampling. Knowledge and practices of participants on HBV prevention and transmission was assessed using a structured questionnaire.

Results

the prevalence of HBV in the LHD and MHD were 5.7% and 7.5% respectively. Pregnant women in the LHD demonstrated good knowledge but adopted poor practices whereas in the MHD, pregnant women demonstrated poor knowledge and adopted poor practices regarding the mode of transmission and prevention of HBV infection. There was a significant association between the prevalence of HBsAg and marital status (p = 0.000) in the LHD and age (p = 0.022) in the MHD.

Conclusion

this study indicated a high prevalence of HBV among pregnant women in the LHD and MHD, knowledge and practices were identified as potential risk factors.

Reviewing of Research Finding of Hepatitis B Virus Infection in Lao People's Democratic Republic

The seroprevalence of hepatitis B virus (HBV) surface antigen (HBsAg)-positive blood donors was 8.7%. The prevalence among males (9.7%) was higher than among females (6.2%). The prevalence of antihepatitis C virus (HCV)-positive blood donors was 1.1%, with no significant differences between males (1.1%) and females (1.0%). Annual positive rates for HBsAg and anti-HCV donors during the years 2003 to 2005 did not differ significantly. In Lao People’s Democratic Republic (PDR), HBV is highly endemic. However, blood donations are only screened for HBsAg, leaving a risk of transmission by HBsAg-negative occult infected donors. Here, we characterized first-time blood donors to assess prevalence of HBV infections and occult infected donors. Despite hepatitis B vaccination at birth and at 6, 10, and 14 weeks of age, HBV infection continues to be endemic in Lao PDR. We carried a cross-sectional serological study in infants, preschool children, school pupils, and pregnant women to determine their burden of disease, risk of infection, and vaccination status. The prevalence of HBsAg carriage in pregnant women is a relevant marker for the risk of mother-to-child HBV transmission. This study aimed to assess the changes in prevalence of HBV infection among pregnant women attending Mahosot Prenatal Clinic (Vientiane).

How to cite this article: Ounavong A. Reviewing of Research Finding of Hepatitis B Virus Infection in Lao People’s Democratic Republic. Euroasian J Hepato-Gastroenterol 2018;8(1):75-76.