Chronic hepatitis B virus infection and rubella susceptibility in pregnant women

Sero-prevalence of hepatitis B virus and compliance with hepatitis B vaccination schedules among outpatient clinic attendees in Nairobi

BACKGROUND

Hepatitis B is becoming a growing public health problem in Kenya. To combat the threat, HBV vaccination should be recommended, particularly for individuals who are not covered by the national immunization program. Vaccination provides sero-protection rates approaching 95% among healthy adults after completing the three-dose vaccination course, but decreases to 87% among those who receive only two doses, emphasizing the importance of completing the three-dose vaccination course. However, data on adult adherence to HBV multi-dose vaccines in Sub-Saharan Africa are limited, despite the fact that this information is critical for prevention. As a result, more research on HBV vaccine dose completion is required. The purpose of this study is to estimate the prevalence of hepatitis B virus infection among out-patient clinic attendees in Nairobi, Kenya, as well as to identify beneficiaries of free vaccination and barriers to completing the recommended vaccine doses.

METHODS

Between July 30th and September 30th, 2015, 2644 outpatient clinic attendees aged ≥ 4 were recruited from three hospitals in Nairobi County, Kenya: Mama Lucy, Riruta, and Loco. Self-administered questionnaires were used to collect socio-demographic information, and blood samples were tested for hepatitis B surface antigen (HBsAg) using the KEMRI HEPCELL Rapid® (Hepatitis B Detection kit) test kit. Individuals who tested negative for HBsAg were given a free course of three doses of HBV vaccine. The vaccination register provided information on the number of doses administered.

RESULTS

The average age of the study population was 31.4 years (range: 4-66), with females accounting for 59.2%. 1.82% (48/2644) of the participants tested positive for HBsAg. Among the 2596 individuals eligible for vaccination, 66% (1720/2596) received at least one dose, and 51.8% (1345/2596) received all three doses. Vaccination acceptance increased with age, with older patients more likely to return for subsequent dose (OR>1 for second and third dose). Unavailability and failure to contact client were cited as significant (p<0.0001) barrier to vaccination completion by 53.7% (666/1226, 95% CI 0.5-0.6) and 37% (454/1226, 95% CI 0.3-0.4) of respondents respectively.

CONCLUSION

The prevalence of HBV infection among outpatient clinic attendees highlights the importance of expanding HBV immunization programs in Kenya. However, given the low vaccination completion rate, there is a need for public awareness of the vaccine's importance in preventing HBV and HBV-related complications.

Hepatitis B - chronic carrier status and pregnancy outcomes: An obstetric perspective

Antenatal screening for hepatitis B surface antigen (HBsAg) only identifies women with hepatitis B virus (HBV) infection for neonatal immunoprophylaxis. It does not reflect the phase of chronic infection, viral genotype and activity, hepatic inflammation, or other co-existing liver disorders. Coinfection with other viruses and micro-organisms may also be present. These factors in various combinations can impact pregnancy outcomes, and they are probably responsible for the conflicting literature on this issue. Pregnancy complications may interact with maternal HBV infection and hepatitis flares, leading to serious and lethal complications. Hepatitis flares are common especially postpartum, and they are unpredictable and unpreventable with antiviral treatment. Evidence on the association between HBsAg seropositivity with gestational diabetes mellitus, preterm birth, increased foetal growth, and reduced pregnancy hypertensive disorders is stronger than other adverse pregnancy outcomes. Baseline assessment of liver function, and viral markers and activity, can delineate the truly high-risk pregnancies for close monitoring.

Impact of the two-dose rubella vaccination regimen on incidence of rubella seronegativity in gravidae aged 25 years and younger

Objective

This study compared the incidence of rubella seronegativity among gravidae of 25 year-old and younger, between those born in Hong Kong after 1983 when the two-dose rubella vaccination was implemented, versus gravidae born before, to examine the impact of the two-dose regimen.

Methods

In this retrospective cohort study, the incidence of antenatal rubella seronegativity in our parturients managed in1997-2015 was analysed by their age from ≤16 to 25 years, and the effect of year of birth was determined adjusting for confounding factors including teenage status, obstetric history, anthropometric factors, and health parameters including anaemia, thalassaemia trait and hepatitis B carrier status.

Results

Among the 12743 gravidae, the 6103 gravidae born after 1983 had overall higher rubella seronegativity (9.1% versus 4.4%, OR 2.061, 95% CI 1.797–2.364), with significant difference (p = 0.006) and inverse correlation (p<0.001) with age, in contrast to the 6640 gravidae born in/before 1983 whom there was significant difference (p = 0.027) but a positive correlation (p = 0.008) with age. For each year of age, the former had significantly higher incidence of rubella seronegativity except for those of ≤16 years. Regression analysis confirmed that birth after 1983 was independently associated with rubella seronegativity (aOR 2.207, 95% CI 1.902–2.562).

Conclusion

There was a significant trend between rubella seronegativity with age in young gravidae, but the pattern was opposite between gravidae born after versus in/before 1983, with the former having a higher incidence of seronegativity at all ages. Young women covered by the two-dose rubella immunisation programme have a paradoxically higher incidence of rubella seronegativity.

A cross-sectional sero-survey on preoperative HBV vaccination policy in Poland

BACKGROUND

A two-dose preoperative vaccination schedule against HBV has been the widely accepted policy in Poland. However, its effectiveness has not yet been assessed.

OBJECTIVE

To evaluate a two-dose preoperative HBV vaccination policy by an assessment of the proportion of patients who don't present a protective level of anti-HBs (<10.0 mIU/ml).

METHODS

Consecutive patients from surgical/gynecologic wards of 12 randomly selected hospitals in West Pomerania, Poland, hospitalized between 2010 and 2013, vaccinated against HBV with a two-dose regimen, were asked to complete an anonymous questionnaire. Serum samples were assayed for anti-HBs with the use of third-generation testing methods. To compare sensitivity versus specificity across a range of values for the ability to predict a dichotomous outcome (a protection against HBV infection) a Receiver operating characteristic (ROC) curve was determined.

RESULTS

There were 193 patients, 58.5% women, median age 52 years. Almost a half (46.0%) of the patients were operated on within 0-60 days of taking the second vaccine dose, 16.2% - 61-180 days after, 37.8% >180 days after. Anti-HBs titer was below a protective level in 49.2% of participants (0.0 mIU/ml in 17.8%, 0.1-9.9 mIU/ml in 31.4%); none of them were aware of this fact. Age ≤ 52 years (OR = 1.89) and having surgery more than 37.5 days after HBV vaccination (OR = 2.70) were associated with greater odds of being protected against HBV infection through vaccination. For the time frame between the second dose implementation and surgery 23 days, a sensitivity of 84% and specificity of 22% for obtaining protection against HBV infection was found, for the time frame >37.5 days - sensitivity remained high (80%), while specificity increased (41%); there was an apparent peek on the ROC curve between 38 and 60 day. In the group vaccinated 0-37.5 days before surgery, less patients had the protective level of anti-HBs titer than in vaccinated 38-60 days before surgery (32.3% vs 60.0%; p = 0.03).

CONCLUSIONS

The success rate in achieving adequate immune protection with two dose HBV vaccination schedule in preoperatively vaccinated patients is relatively low, especially among those vaccinated less than five weeks prior to surgery. In more than a third of cases the standard three-dose regimen could have been implemented, as participants had time to complete a third dose. Current recommendations regarding a preoperative policy with a 2-dose vaccination schedule in Poland should be revised; the best time to perform surgery after the implementation of the second dose of vaccine in the context of patient protection against HBV infection would be between 38 and 60 days.

Sociodemographic and economic characteristics of susceptibility to rubella among women preparing for pregnancy in rural China

OBJECTIVES

Infection with rubella virus during pregnancy can result in congenital defects and adverse pregnancy outcomes. The risk of rubella infection is greatly determined by the level of rubella antibodies in the serum. A survey of rubella antibody seronegativity rates was conducted in 780 000 women in rural China who were planning a pregnancy, in order to evaluate the herd susceptibility in different age groups and by high, middle, and low GDP per capita regions.

METHODS

In order to evaluate the herd susceptibility to rubella, a nationwide population-based study of rural Chinese women who were planning to have a baby and who were aged 21-49 years was instigated. As a part of the National Free Pre-conception Health Examination Project covering 29 provinces in 2012, a physical check-up program was provided to women who planned to become pregnant within the next 6 months. All medical data were from serological samples tested by ELISA, and the participants' immunity status was categorized based on levels of rubella antibodies. Economic data were also collected to explore the association between herd susceptibility and socioeconomic characteristics in the women of childbearing age.

RESULTS

A total 264 306 of 782 293 recruited women preparing for pregnancy tested susceptible to rubella (33.79%). The seronegativity rate in women with a history of vaccination was significantly lower than that in women who had not received the vaccination or did not know their vaccination history (23.76%, 33.70%, and 35.68%, respectively). The seronegativity rates were 26.89%, 37.86%, and 32.61% in high, middle, and low GDP per capita areas, respectively. After stratified analysis and adjusting for other factors by multiple logistic regression, the lower seronegativity rates in women in high GDP per capita regions compared to women in middle and low GDP per capita regions remained in the different age groups and subgroups of immunization history.

CONCLUSIONS

There is a clear difference in rubella-specific susceptibility among rural women preparing for pregnancy of different sociodemographic and economic backgrounds. The number of rubella-susceptible rural women preparing for pregnancy, especially in relatively low GDP per capita regions in China, was high. Offering rubella vaccination to women who are rubella-susceptible and who plan to become pregnant should become one of the priorities in the field of public health work in China.

Prior pregnancy and antenatal rubella sero-negativity-evidence of persistent maternal immunologic alteration?

PROBLEM

It is unclear if the immunologic alterations induced by pregnancy could persist.

METHOD OF STUDY

Antenatal rubella sero-negativity was correlated with gravidity, abortions and parity in 112 083 gravidae managed during 1997-2015, with further analysis stratified for factors known to influence rubella serology.

RESULTS

The 10.2% sero-negative gravidae had different characteristics, and the incidence showed significant difference and positive trend (P<.001 for both) with gravidity, abortions and parity. The pattern remained consistent when analysis was stratified for advanced age, high body mass index and medical history, but was negated by hepatitis B virus infection except for abortions, and by high body mass index for parity. For gravidity 2-4, no difference in rubella sero-negativity was found between gravidae with all previous pregnancies ended in abortion vs delivery.

CONCLUSION

Prior pregnancies diminished rubella immunity in a dose-dependent manner, which may be a reflection of the cumulative effect of pregnancy-associated maternal immunologic alteration.

Pregnancy and maternal chronic hepatitis B infection-Evidence of reproductive advantage?

PROBLEM

As multiparas have high prevalence of chronic hepatitis B virus (HBV) infection, we examined here the relationship between the number of pregnancies with HBV infection.

METHOD OF STUDY

Retrospective cohort study examining the prevalence of HBV infection by actual gravidity and parity in 104 242 gravidae managed during 1997-2013.

RESULTS

Infection rate increased from 8.5% to 10.6% for G1 to G≥6 and from 8.8% to 10.0% for P0 to P≥3 (P<.001). When stratified by parity, correlation with gravidity was maintained in the nulliparous gravidae. For the same gravidity, increasing parity was associated with higher rate of HBV infection for G2 and G3. Multiparas had higher HBV infection prevalence (all >10%) than nulliparas (<10%) for G2 to G≥4.

CONCLUSION

Prior pregnancies, especially successful ones, are associated with increased HBV infection in an endemic population, which could have enhanced reproduction and in the process facilitated its transmission to the following generations.

Hepatitis B virus infection status and infertility causes in couples seeking fertility treatment-Indicator of impaired immune response?

PROBLEM

The relationship between hepatitis B (HBV) infection in infertile couples seeking in vitro fertilization (IVF) treatment and infertility causes is unknown.

METHODS OF STUDY

A total of 831 infertile couples attending our unit seeking IVF during January to December 2015 were recruited.

RESULTS

HBV infection was found in 6.3% and 7.3% of female and male partners, respectively, and infection in one or both partners was associated with less primary infertility (44.2% vs 55.1%, P=.038). Infected female partners had increased tubal (69.2% vs 43.2%, P<.001) and uterine (13.7% vs 3.1%, P<.001) causes and reduced idiopathic infertility, while infected male partners were associated with increased tubal (62.3% vs 43.4%, P=.004) causes and reduced endometriosis (62.3% vs 73.9%, P=.050).

CONCLUSION

Our results suggest HBV infection in either partner was associated with tubal infertility. HBV infection in either partner probably increases the risk of pelvic infection in female partner through impaired immune response to sexually transmitted infections, with consequent tubal damage and infertility.

A cross-sectional serosurvey on hepatitis B vaccination uptake among adult patients from GP practices in a region of South-West Poland

BACKGROUND

Hepatitis B is a significant health burden in Poland with nosocomial transmission being the main source of infection. Therefore, HBV vaccination is widely recommended for those not covered by the national immunisation program.

OBJECTIVE

To assess the coverage and influencing determinants of HBV vaccination among adult patients attending GP clinics as well as to establish serological status in terms of HBV infection.

METHODS

Patients who were seen consecutively in March 2013 at four randomly selected GP practices located in Zgorzelec county, in south-western part of Poland, were invited to participate and complete questionnaires on socio-demographic data and other factors related to vaccination. A pilot study was done in one urban GP practice in the city of Gryfino (Gryfino county), the results have been included in the study. Patients' immunisation status was assessed basing on vaccination cards and anti-HBs titer with the use of third-generation testing methods. In addition, serum samples were assayed for anti-HBc total.

RESULTS

Response rate: 99.3 %. Of 410 participants (66.1 % females, median age 56 years), 55.4 % (95%CI:50.5-60.1 %) were previously vaccinated; in those 11.5 % took 2 doses, 66.1 % - 3 doses,18.1 % - 4 doses. Elective surgery was the main reason (57.7 %) for HBV immunization, 4.8 % - were vaccinated due to recommendations by GPs. The multivariable logistic regression model revealed that living in a city (OR 2.11), and having a surgery in the past (OR 2.73) were each associated with greater odds of being vaccinated. Anti-HBc total prevalence among those unvaccinated was 13.6 % (95%CI:9.3 %-19,5 %), and 7.2 % (95%CI:4.4-11.8 %) among those vaccinated.

CONCLUSIONS

Low HBV immunization coverage among adult patients from GP clinics and the presence of serological markers of HBV infection among both - those unvaccinated and vaccinated call for comprehensive preventative measures against infection, including greater involvement of family doctors. Although interventions should cover the whole population, inhabitants living in the rural areas should be a group of special interest. Preoperative immunization for HBV seems to be an efficient public health tool to increase the vaccination uptake.

Rubella seronegativity in antenatal screening - Is it influenced by the introduction of universal childhood rubella immunization?

OBJECTIVE

This study examined the impact of rubella immunization, implemented in Hong Kong in phases since 1978, on antenatal rubella serological status in Chinese women.

METHODS

In a retrospective cohort study, the incidence of antenatal rubella seronegative status in our parturients managed from 1998 to 2013 was analyzed by their year-of-birth as follows: <1965 (no childhood immunization), 1965-1982 (single dose at Primary 6), and ≥1983 (two doses at age 12 months and 12 years), adjusting for other factors including age, parity, body mass index, place-of-birth status and hepatitis B surface antigen (HBsAg) status.

FINDINGS

Rubella seronegativity decreased from 12.9%, 10.5%, to 9.8% respectively, and correlated inversely (P<0.001) with year-of-birth cohorts. Despite similar demographic profiles, this correlation was found only in Hong-Kong-born women (from 12.6%, 7.5% to 6.5% respectively), who also had significant lower incidences of rubella seronegativity (OR 0.73, 0.31 and 0.29 respectively) and HBsAg seropositivity (OR 1.09, 0.63 and 0.48 respectively) than China-born women. On regression analysis, rubella seronegativity was actually significantly increased following the implementation of immunization (aOR 1.20) while it was the reverse for non-residents (aOR 0.61).

CONCLUSION

Although rubella seronegativity decreased with immunization, the effect was less than expected when adjusted for other risk factors.

Some factors affecting rubella seronegative prevalence among pregnant women in a North West England region between April 2011 and March 2013

BACKGROUND

Rubella is usually a mild viral illness, but during pregnancy, it can have potentially devastating effects causing fetal losses and severe congenital malformations (congenital rubella syndrome). Rubella is now rare in most developed countries following a successful vaccination programme. We aimed to investigate differences in epidemiological profile of pregnant women screened antenatally in Liverpool to identify risk factors for rubella immunity.

METHODS

All samples were tested with the Elecsys Rubella IgG immunoassay kit. A result <10 IU/ml was considered to be seronegative.

RESULTS

The seronegativity prevalence among pregnant women in Liverpool (6.3%) is higher than average value for the North West region (3.7%). The seronegative rates varied with age (15.4% for <15 years, 18.7% for 15-20 years, compared with 2% for 30-35 years). The areas with the highest seronegative rates correspond with areas of Liverpool with high pockets of socioeconomic deprivation.

CONCLUSION

The highest proportion of seronegative women were among the youngest age groups. Local areas with highest level of deprivation should be given priority and additional resources to develop targeted programmes and pathways to implement appropriate interventions such as MMR catch-up programmes and put in place arrangements for offering MMR vaccination in maternity units.

Pregnancy outcomes among chronic carriers of hepatitis B virus

OBJECTIVE

To compare pregnancy outcomes of women with chronic HBV infection with those of HBV-negative women.

METHODS

A retrospective cohort study was undertaken to analyze singleton pregnancies of women without medical/surgical disease and with known HBsAg status. Pregnancy outcome measures were compared among the control group, women with positive HBsAg status (case group), and those with positive HBeAg status.

RESULTS

Among 26 350 enrolled pregnant women, 21 812 in the control group and 1446 in the case group were compared. Only the proportion of preterm births was significantly higher among pregnancies with positive HBsAg status (RR 1.013 [95% CI, 1.001-1.025]). Among women with positive HBsAg status who had been screened for HBeAg, GDM was significantly higher among women with positive HBeAg status (RR 1.434 [95% CI, 0.999-2.057]). Preterm births and low birth weight were also significantly higher among women with positive HBeAg status (RR 1.250 [95% CI, 1.000-1.563] and 1.258 [95% CI, 1.053-1.505], respectively).

CONCLUSION

Chronic carriers of HBV had a minimally increased risk of preterm birth and low birth weight but the risk was more pronounced in women with positive HBeAg status. Women with positive HBeAg status also had an increased risk of GDM.

Maternal hepatitis B surface antigen status and incidence of pre-eclampsia

The relationship between chronic hepatitis B virus (HBV) infection with atherosclerosis and cardiovascular disorders remains unclear, and the impact of maternal HBV infection on the development of pregnancy-induced hypertension (PIH) and pre-eclampsia (PE) is also controversial. This retrospective cohort study was conducted to examine the relationship between maternal hepatitis B surface antigen (HBsAg) status with PIH and PE in singleton pregnancies that delivered at 24 weeks of gestation and beyond. Among the 86 537 cases in the cohort, 10% were HBsAg positive, and overall 2.0% had PIH, of whom 56.3% developed PE. HBsAg-positive women had higher weight and body mass index (BMI), but lower incidences of advanced age, nulliparity, PIH (1.6% vs 2.0%, P = 0.007) and PE (0.8% vs 1.1%, P = 0.005). On multiple logistic regression analysis adjusting for the effects of nulliparity, advanced age, high BMI, and underlying renal, cardiac and autoimmune diseases, HBsAg carriage was associated with significantly reduced incidence of PIH (aOR 0.79, 95% CI 0.66-0.95) and PE (aOR 0.71, 95% CI 0.56-0.91). Our results indicate that maternal HBsAg carriage is independently associated with reduced PE. As chronic HBV infection alters the immune response of the individual, our observation could be related to enhanced maternal immunotolerance of the foetus and hence a reduction in the incidence of PE. The implications of our findings on the long-term health outcome of the infected women, from cardiovascular morbidity to malignancies, warrant further studies.

Impact of neonatal hepatitis B vaccination programme on age-specific prevalence of hepatitis B infection in teenage mothers in Hong Kong

We examined the impact of the neonatal hepatitis B immunization programme, first provided to all neonates born to mothers screened positive for hepatitis B surface antigen (HBsAg) in late 1983, on the age-specific prevalence of HBsAg carriage in teenage mothers managed in 1998–2008. HBsAg carriage was found in 2.5%, 2.7%, 8.8% and 8.0% of mothers aged ≤ 16, 17, 18, and 19 years, respectively (P=0.004), which was also correlated with advancing age (P=0.011). While neither difference nor correlation with age was found in mothers born before 1984, the prevalence of 1.2%, 1.5%, 7.1% and 8.3%, respectively, was significantly different among (P=0.008) and correlated with (P=0.002) age in mothers born 1984 onwards. Regression analysis indicated there was a significantly higher incidence of HBsAg carriage from age 17 onwards (adjusted odds ratio 2.55, 95% confidence interval 1.07–6.10, P=0.035), suggesting that the protective effect of the vaccine declined in late adolescence.

Maternal HBsAg status and infant size--a Faustian bargain?

Information on the impact of maternal hepatitis B virus (HBV) infection on pregnancy outcome is conflicting. Some studies reported an association with increased infant birthweight, which could be interpreted as advantageous to pregnancy. A retrospective study was performed to compare birthweight outcome between 6261 and 55,817 singleton pregnancies in mothers screened positive and negative for hepatitis B surface antigen (HBsAg), respectively. The HBsAg positive women were younger, had higher body mass index (BMI) and incidence of overweight, but less gestational weight gain, and were associated with increased macrosomia (birthweight ≥4000 g) in mothers <35 years (odds ratio, OR, 1.28), BMI ≥25 kg/m(2) (OR 1.24), without gestational diabetes mellitus (GDM, OR 1.19), and in male infants (OR 1.18). It was also associated with increased large-for-gestational age (LGA, birthweight >90th percentile) infants in nulliparas (OR 1.13), age <35 years (OR 1.12), BMI ≥25 kg/m(2) (OR 1.19), with (OR 1.36) and without (OR 1.09) GDM, and in male infants (OR 1.13). When the effects of high BMI, advanced age, GDM, and male infants were controlled for, positive HBsAg was significantly associated with macrosomic (adjusted odds ratio, aOR, 1.15) and LGA (aOR 1.11) infants. In view of the latest findings on the association between high infant birthweight with increased risk of obesity, diabetes mellitus, and various forms of malignancies from childhood to adulthood, further studies are warranted to determine if maternal hepatitis B infection would impact adversely on the long-term health of the offspring through its effect on increasing birthweight.