Streptococcus agalactiae colonization and correlation with HIV-1 and HBV seroprevalence in pregnant women from Zimbabwe

Vertical transmission of hepatitis B virus in the WHO African region: a systematic review and meta-analysis

BACKGROUND

More new infections with hepatitis B virus (HBV) occur annually in the WHO African region than in the rest of the world combined. We did a systematic review and meta-analysis to estimate the prevalence of hepatitis B surface antigen (HBsAg) in pregnant women and vertical transmission events in the region.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Embase, Scopus, Africa Index Medicus, and Africa Journals Online for publications between Jan 1, 1992, and Jan 7, 2024, with no language restrictions. HBsAg prevalence and vertical transmission (HBsAg positivity in children aged 6-12 months) were estimated with the use of binomial mixed models with logit links, stratified by infant vaccination status. We estimated HBsAg prevalence for subregions of Africa and for the WHO African region by weighting by estimated livebirths for each subregion. We estimated transmission events using WHO and UNICEF vaccine coverage data and UN population estimates.

FINDINGS

We included 113 studies reporting on HBsAg prevalence from 190 983 pregnant women and 11 studies reporting on vertical transmission. HBsAg prevalence in women receiving antenatal care in the WHO African region (based on 2014-23 data) was 6·2% (95% CI 5·3-7·2). No relationship between risk of bias and HBsAg prevalence was observed. In 2022, an estimated 172 000 vertical transmission events (95% CI 82 000-383 000) occurred (0·4% of livebirths), a fall from a peak of 339 000 (149 000-634 000; 1·2% of all livebirths) in 2001. Increasing birth dose vaccination coverage to the WHO target of 90% could reduce vertical transmission by 43·7% (95% CI 11·6-78·0) to 97 000 events per year (95% CI 58 000-160 000). Adding maternal antiviral prophylaxis with 90% coverage could reduce transmission by 86·3% (95% CI 78·4-94·6) to 24 000 events per year (95% CI 14 000-39 000; 0·06% of livebirths) and achieve WHO elimination targets.

INTERPRETATION

Vertical transmission is an important contributor to HBV transmission in the WHO African region. Scaling up of hepatitis B birth dose vaccination and antiviral prophylaxis is urgently needed, which could achieve elimination of vertical transmission.

FUNDING

Wellcome Trust.

Prevalence and trends of hepatitis B and C virus biomarkers in Zimbabwe: comparative analyses of a nation's blood-donor surveillance data and meta-analyses of population studies

BACKGROUND

The disproportionate burden of viral hepatitis, particularly hepatitis B virus (HBV) is experienced by people living in low-resourced sub-Saharan Africa, where the estimated prevalence is 3-7 times the global average. Therefore to inform policy, we describe the seroprevalence and trends of hepatitis C (HCV) and HBV biomarkers: anti-HCV antibody and hepatitis B surface antigen (HBsAg), respectively, in Zimbabwe.

METHODS

We analysed data from 181,248 consecutive blood-donors, examined between January 2015 through December 2018. Additionally, we conducted a comprehensive literature review using PubMed and African Journals Online databases, meta-analysing selected papers from Zimbabwe, published between 1970 and 2020, that met specific criteria.

RESULTS

Overall age-standardized prevalence rate (ASPR) for anti-HCV was 8.67 (95%CI, 0.25-17.09) per 100,000, while that for HBsAg was 2.26 (95%, 1.89-2.63) per 1000 blood-donors, per year. Meta-analysis of 9 studies comprising 220,127 persons tested for anti-HCV revealed ASPR of 0.05% (95% 0%-0.19%) in blood-donors and 1.78% (95%CI, 0.01%-5.55%) in the general population, for an overall pooled ASPR of 0.44 (95%CI, 0.19%-0.76%). 21 studies comprising 291,784 persons tested for HBsAg revealed ASPR of 0.65% (95%CI, 0.31%-1.00%) in blood-donors and 4.31% (95%CI, 1.77%-6.50%) in the general population for an overall pooled ASPR of 4.02% (95%CI, 3.55%-4.48%), after HBV vaccine introduction. HBsAg prevalence was significantly higher before HBV vaccine introductions.

CONCLUSIONS

The prevalence of HBV is decreasing, consistent with the introduction of HBV vaccination, while HCV prevalence is increasing in Zimbabwe. This highlights the need for Improved blood-donor screening and more informative biomarker studies, particularly among repeat donors and children.

Antenatal hepatitis B virus sero-prevalence, risk factors, pregnancy outcomes and vertical transmission rate within 24 months after birth in a high HIV prevalence setting

BACKGROUND

Despite the availability of an effective vaccine, chronic hepatitis B virus (HBV) infections remain a major cause of liver cirrhosis and hepatocellular carcinoma. HBV burden in pregnancy, risk factors and the timing of mother to child transmission remain poorly described especially during this era of lifelong use of Tenofovir/Lamivudine/Efavirenz as firstline for HIV treatment. We aimed to determine the burden of HBV in pregnancy and infants receiving their first dose of HBV vaccine 6 weeks after birth in a high HIV-prevalence setting.

METHODS

Pregnant women ≥ 20 weeks' gestational age were enrolled and followed up as mother-infant dyads from delivery, 6, 24 and 96 weeks after birth. HBV surface antigen (HBsAg) was tested (fresh plasma, immunochromatography) in pregnancy. Women testing HBsAg-seropositive were further evaluated for other four HBV-biomarkers. Maternally HBV exposed babies were tested for HBsAg from birth and HBs-antibodies from 6 months of age. Maternal-infant factors were tested in univariable and multivariable analyses for predictors of HBsAg-seropositivity.

RESULTS

Six hundred HIV-uninfected and 608 HIV-infected women on Tenofovir/Lamivudine/Efavirenz-regimen with median (interquartile range) 350: (87-1477) days of therapy use were enrolled. The overall HBsAg-seroprevalence was 32/1208: 2.65%, 95% confidence interval (CI) [1.74, 3.55]; being 7/600: 1.17%, 95% CI [0.37, 1.97] and 25/608: 4.11%, 95% CI [2.52, 5.68] in HBsAg-monoinfected and HBsAg/HIV-coinfected respectively, disproportionately detected in 31/32: 96.9%, 95% CI [90.8, 100] women presumably HBV-unvaccinated in infancy. HBV exposed babies tended to be born prematurely (< 37 weeks); 15.2% versus 9.9% in the HBV-unexposed, p = 0.009. In multivariate logistic regression-models with variable elimination, HIV-infection and reported tooth extractions predicted antenatal HBsAg-seropositivity; odds ratios (CI): 3.85 (1.61-10.7) and 2.46 (1.07-5.34), respectively. None of the exposed infants were HBsAg-seropositive neither before nor after 6 weeks of age. No HBs-antibodies were detected in 23.3% of HBsAg-exposed infants at two years despite having successfully completed the HBV vaccination schedule.

CONCLUSION

Low and moderate HBV endemics were observed in HIV-uninfected and HIV-infected pregnant women, respectively. This underscores the need to routinely screen for HBV in pregnancy, especially the HIV-infected attending antenatal-care. Being HIV-infected and reported tooth extractions were independent risk factors for maternal HBsAg-seropositivity. Vertical and child horizontal transmissions were both absent, probably due to ~ the 50% frequency of antenatal anti-HBe-antibodies observed. Of concern was the absence of anti-HBs-antibodies in 23.3% of fully vaccinated/maternally HBV-exposed infants by two years. Absence of molecular diagnosis may have underestimated HBV burden.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov , trial registration number: NCT04087239.

Large-scale microbiome data integration enables robust biomarker identification

The close association between gut microbiota dysbiosis and human diseases is being increasingly recognized. However, contradictory results are frequently reported, as confounding effects exist. The lack of unbiased data integration methods is also impeding the discovery of disease-associated microbial biomarkers from different cohorts. Here we propose an algorithm, NetMoss, for assessing shifts of microbial network modules to identify robust biomarkers associated with various diseases. Compared to previous approaches, the NetMoss method shows better performance in removing batch effects. Through comprehensive evaluations on both simulated and real datasets, we demonstrate that NetMoss has great advantages in the identification of disease-related biomarkers. Based on analysis of pandisease microbiota studies, there is a high prevalence of multidisease-related bacteria in global populations. We believe that large-scale data integration will help in understanding the role of the microbiome from a more comprehensive perspective and that accurate biomarker identification will greatly promote microbiome-based medical diagnosis.

Group B Streptococcus vaginal colonization in pregnant women living with HIV infection: prevalence and antibiotic susceptibility at HIV referral centers in Lagos, Nigeria

OBJECTIVES

Group B Streptococcus (GBS) colonization of the genital tract is often asymptomatic yet associated with increased risks of maternal and neonatal morbidity especially amongst women living with HIV infection. The objectives of this study were to determine the prevalence of GBS colonization of the genital tract in women living with HIV infection and antibiotic susceptibility of GBS in the genital tract.

METHOD

This cross-sectional study recruited 244 pregnant women (122 women living with HIV infection and 122 HIV-uninfected women) between 35 and 37 weeks of gestation. GBS colonization was determined by collecting lower vaginal and anal swabs at recruitment. Swabs were cultured in Todd Hewitt's broth and confirmed by Christie, Atkins, and Munch-Peterson (CAMP) test. Most recent CD4 count and viral load estimates were retrieved from the women's records. Maternal and neonatal outcomes and antibiotic susceptibility were assessed. Statistical analysis was performed at 95% confidence interval at a statistical significance of p < .005.

RESULTS

The prevalence of GBS colonization of the genital tract in all participants was 3.3%; GBS was isolated in 4 (3.3%) of 122 pregnant women living with HIV. No woman with a GBS-colonized genital tract developed puerperal sepsis and no neonatal infection occurred in neonates born to GBS-positive women, irrespective of HIV infection status. In women living with HIV, GBS isolate was resistant to Ampicillin (100%), Ceftriaxone (100%), Vancomycin (100%), yet partially sensitive to Ciprofloxacin (50%).

CONCLUSION

Pregnant women living with HIV do not have an increased risk of genital GBS colonization. Vaginal GBS colonization was not associated with an adverse perinatal outcome. Antibiotic use for GBS colonization should be based on sensitivity pattern and not empiric.

Hepatitis B virus infection and hepatocellular carcinoma in sub-Saharan Africa: Implications for elimination of viral hepatitis by 2030?

Elimination of viral hepatitis in sub-Saharan Africa by 2030 is an ambitious feat. However, as stated by the World Health Organization, there are unprecedented opportunities to act and make significant contributions to the elimination target. With 60 million people chronically infected with hepatitis B virus (HBV) of whom 38800 are at risk of developing highly fatal hepatocellular carcinoma (HCC) every year, sub-Saharan Africa faces one of the greatest battles towards elimination of viral hepatitis. There is a need to examine progress in controlling the disproportionate burden of HBV-associated HCC in sub-Saharan Africa within the context of this elimination target. By scaling-up coverage of hepatitis B birth dose and early childhood vaccination, we can significantly reduce new cases of HCC by as much as 50% within the next three to five decades. Given the substantial reservoir of chronic HBV carriers however, projections show that HCC incidence and mortality rates in sub-Saharan Africa will double by 2040. This warrants urgent public health attention. The trends in the burden of HCC over the next two decades, will be determined to a large extent by progress in achieving early diagnosis and appropriate linkage to care for high-risk chronic HBV infected persons.

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.

Group B Streptococcus (Streptococcus agalactiae)

Invasive disease due to group B Streptococcus infection (Streptococcus agalactiae) results in a wide spectrum of clinical disease. In North America, serotypes Ia, Ib, II, III, and V are most frequently associated with invasive disease. Group B Streptococcus remains a continuing source of morbidity and mortality in high-risk populations, including pregnant women, neonates, and the elderly; an increasing incidence of invasive disease has been observed in nonpregnant adults. Group B Streptococcus remains the most common culture-confirmed neonatal bacterial infection in the United States and is a significant source of neonatal morbidity globally. Intrapartum antibiotic prophylaxis has reduced the incidence of early-onset neonatal disease without a notable impact on the incidence of late-onset neonatal disease. Penicillin G remains the mainstay of therapy, although reduced penicillin susceptibility has been observed in select isolates. Increased frequency of resistance to non-beta-lactam antibiotics, including clindamycin, erythromycin, and fluoroquinolones, has been observed, with some isolates demonstrating resistance to vancomycin. The development and implementation of strategies to identify hosts, treat judiciously with antimicrobials with the narrowest spectra, and prevent invasive disease, with vaccines, are essential to reduce the burden of group B Streptococcus disease.

Streptococcus agalactiae maternal colonization, antibiotic resistance and serotype profiles in Africa: a meta-analysis

Background

Maternal rectovaginal colonization with Streptococcus agalactiae (Group B Streptococcus or GBS) is the most common route for the GBS disease in the perinatal period. The knowledge of maternal colonization, antibiotic resistance and serotype profiles is substantially needed to formulate the broad vaccine. However, it has not been estimated in Africa. This meta-analysis was aimed to determine the pooled prevalence of colonization, antibiotic resistance and serotype profiles of GBS reported in Africa.

Methods

Potentially relevant studies from 1989 to 31th January, 2019 were retrieved from the Medline/PubMed, EMBASE, HINARI online databases, periodicals and by requesting authors. Unpublished studies retrieved from grey literature through Google and Google Scholar. Pooled estimates were calculated using the random effect model. Subgroup analysis was done to investigate the burden of colonization across sub-regions, sampling site and countries. Summary estimates were presented using words, Forest plots and Tables. Heterogeneity was assessed using the I² statistic.

Results

Eighty-three articles were assessed, of which 57 studies conducted in five sub-regions with 21 countries (22,206 pregnant women) met pre-specified inclusion criteria. The overall estimate of recto-vaginal colonization was 19.3% (95% CI 16.9, 21.7). The highest estimate was observed in Southern Africa, 23.8% (95% CI 18.7, 28.9), followed by Northern Africa, 22.7% (95% CI 18.2, 27.2) while the lowest was driven from the Eastern Africa, 15.4% (95% CI 12.1, 18.7). Considerable heterogeneity across and within regions, sampling site, screening methods and countries (I² > 75%); and the publication bias were observed (p = 0.031). GBS showed the highest resistance to tetracycline. Resistance to penicillin, amoxicillin, chloramphenicol, ampicillin, ceftriaxone, ciprofloxacin, erythromycin, vancomycin and clindamycin also observed. The V, III, Ia, Ib, and II serotypes altogether were accounted 91.8% in the African studies.

Conclusions

The pooled estimate of the maternal colonization with GBS was 19.3% which is equivalent with other many primary and review reports worldwide. The most antibiotic resistance estimate was recorded in the tetracycline followed by penicillin. Five serotypes were the most prevalent in Africa and more data on the antibiotic résistance and serotype distribution patterns are needed from developing countries to devise the effective preventive measures. In addition, the antibiotic susceptibility test methods used in the Africa shall be assessed for its quality.

Trial registration Prospero Registration Number CRD42018094525

Streptococcus agalactiae from Ethiopian pregnant women; prevalence, associated factors and antimicrobial resistance: alarming for prophylaxis

Background

Maternal Streptococcus agalactiae (Group B Streptococcus, GBS) colonization rates and its antibiotic resistance patterns provide important information useful in guiding prevention strategies. There is a paucity of evidence about GBS in the Amhara National Regional State, Ethiopia.

Objective

To determine colonization prevalence, associated risk factors, and antibiotics resistance including inducible clindamycin resistance patterns of GBS among Ethiopian pregnant women.

Methods

A prospective cross-sectional study was conducted from 1st December 2016 to 30th November 2017 at the University of Gondar Referral hospital delivery ward. Combined recto-vaginal swabs were collected from 385 pregnant women and analyzed at the University of Gondar Bacteriology Laboratory by using LIM broth and 5% defibrinated sheep blood agar culture methods. Isolates were identified by using colony morphology, gram reaction, hemolysis, and CAMP test. Antibiotic susceptibility test was done using the disc diffusion method. Double disc diffusion method was used to identify inducible clindamycin resistance isolates. Data were analyzed by SPSS version 20 software. p ≤ 0.05 was considered as statistically significant.

Results

The overall prevalence of maternal GBS colonization was 25.5% (95% CI 21–29.5%). Experiencing meconium stained amniotic fluid (AOR = 3.018, 95% CI 1.225, 7.437), and longer duration of premature rupture of membrane (AOR = 1.897, 95% CI 1.014, 3.417) were statistically significant to maternal colonization. Furthermore, GBS resistant to 0 (8.2%), 1 (25.5%) and 3 (39.8%) or more antibiotics were identified. A D-test showed 15.2% inducible clindamycin resistant GBS. Constitutive macrolide lincosamide–streptogramin_B, L-, and M-phenotypes were also detected.

Conclusions

Maternal GBS colonization rate in this study was higher compared to the previous reports in Ethiopia. This much prevalence and antibiotics resistance results are the clue to which attention shall be given to this bacterium during management of pregnant women and the newborns.

Role of HIV exposure and infection in relation to neonatal GBS disease and rectovaginal GBS carriage: a systematic review and meta-analysis

Streptococcus agalactiae (GBS) is the leading cause worldwide of neonatal sepsis. We sought to assess to which extent HIV exposure of neonates is associated with GBS neonatal disease. Furthermore, we assessed to which extent HIV infection in women is associated with maternal rectovaginal GBS carriage, the single most important risk factor for GBS neonatal disease. We searched Pubmed, Embase, and Web of Science for studies assessing the association between neonatal GBS disease and HIV-status of the mother and studies that assessed the association between rectovaginal GBS colonization and HIV status in women. HIV-exposed uninfected neonates were more than twice as likely to have neonatal GBS disease compared to unexposed neonates. HIV-exposed neonates were not at increased risk for early-onset neonatal disease, but were 4.43 times more likely to have late-onset neonatal GBS disease. There was no significant association between HIV infection status and rectovaginal GBS carriage. Public health interventions preventing neonatal GBS disease are urgently needed for the increasing group of HIV-exposed neonates. A framework integrating and explaining our findings highlights opportunities for the clinical practice and global health policy to prevent disease. Well-designed studies should clarify the relation between HIV-status and GBS carriage.

The status of hepatitis B control in the African region

The World Health Organization (WHO) African Region has approximately 100 million people with chronic hepatitis B virus (HBV) infection. This review describes the status of hepatitis B control in the Region. We present hepatitis B vaccine (HepB) coverage data and from available data in the published literature, the impact of HepB vaccination on hepatitis B surface antigen (HBsAg) prevalence, a marker of chronic infection, among children, HBsAg prevalence in pregnant women, and risk of perinatal transmission. Lastly, we describe challenges with HepB birth dose (HepB-BD) introduction reported in the Region, and propose strategies to increase coverage. In 2015, regional three dose HepB coverage was 76%, and 16(34%) of 47 countries reported ≥ 90% coverage. Overall, 11 countries introduced HepB-BD; only nine provide universal HepB-BD, and of these, five reported ≥ 80% coverage. From non-nationally representative serosurveys among children, HBsAg prevalence was lower among children born after HepB introduction compared to those born before HepB introduction. However, some studies still found HBsAg prevalence to be above 2%. From limited surveys among pregnant women, the median HBsAg prevalence varied by country, ranging from 1.9% (Madagascar) to 16.1% (Niger); hepatitis B e antigen (HBeAg) prevalence among HBsAg-positive women ranged from 3.3% (Zimbabwe) to 28.5% (Nigeria). Studies in three countries indicated that the risk of perinatal HBV transmission was associated with HBeAg expression or high HBV DNA viral load. Major challenges for timely HepB-BD administration were poor knowledge of or lack of national HepB-BD vaccination guidelines, high prevalence of home births, and unreliable vaccine supply. Overall, substantial progress has been made in the region. However, countries need to improve HepB3 coverage and some countries might need to consider introducing the HepB-BD to help achieve the regional hepatitis B control goal of < 2% HBsAg prevalence among children < 5 years old by 2020. To facilitate HepB-BD introduction and improve timely coverage, strategies are needed to reach both facility-based and home births. Strong political commitment, clear policy recommendations and staff training on HepB-BD administration are also required. Furthermore, high quality nationally representative serosurveys among children are needed to inform decision makers about progress towards the regional control goal.

Hepatitis B serological markers and plasma DNA concentrations

OBJECTIVES

To examine hepatitis B (HBV) serological markers and plasma DNA concentrations in a large group of untreated HBV/HIV-coinfected individuals in two sub-Saharan settings.

DESIGN

Baseline analysis of a randomized controlled trial.

METHODS

DART was a large trial of treatment monitoring practices in HIV-infected adults with advanced disease starting antiretroviral therapy at centres in Kampala or Entebbe, Uganda (n = 2317) and Harare, Zimbabwe (n = 999). HBV serological markers [antibody to HBV core antigen, HBV surface antigen (HBsAg), antibody to HBV surface antigen, HBV 'e' antigen (HBeAg), and antibody to hepatitis B 'e' antigen] and plasma HBV DNA viral load were measured retrospectively on stored baseline samples. Logistic regression was used to examine associations with baseline demographic and clinical factors.

RESULTS

The rate of HBsAg positivity was significantly higher in Zimbabwe than Uganda (12.2 vs. 7.7%, adjusted odds ratio = 1.54, P < 0.001) despite a similar prevalence of antibody to HBV core antigen (56.3 vs. 52.4%) in the two settings. Overall, HBsAg positivity was associated with male sex (adjusted odds ratio = 1.54, P < 0.001) but not with age, WHO disease stage, or CD4 cell count. HBeAg was detected among 37% of HBsAg-positive patients, with higher rates among those with advanced WHO stage (P = 0.02). Also in HBsAg-positive patients, HBV DNA was undetectable in 21%, detectable but below the level of quantification in 14%, and quantifiable in 65%. A total of 96% of HBeAg-positive and 70% of HBeAg-negative patients had detectable HBV DNA; 92 and 28% of patients, respectively, had HBV DNA viral load more than 2000 IU/ml.

CONCLUSION

High rates of HBV coinfection were observed, highlighting the importance of ensuring that coinfected patients receive an antiretroviral regimen, whether first-line or not, that is active against both viruses.

Increased Risk of Group B Streptococcus Invasive Infection in HIV-Exposed but Uninfected Infants: A Review of the Evidence and Possible Mechanisms

Group B Streptococcus (GBS) is a major cause of neonatal sepsis and mortality worldwide. Studies from both developed and developing countries have shown that HIV-exposed but uninfected (HEU) infants are at increased risk of infectious morbidity, as compared to HIV-unexposed uninfected infants (HUU). A higher susceptibility to GBS infections has been reported in HEU infants, particularly late-onset diseases and more severe manifestations of GBS diseases. We review here the possible explanations for increased susceptibility to GBS infection. Maternal GBS colonization during pregnancy is a major risk factor for early-onset GBS invasive disease, but colonization rates are not higher in HIV-infected compared to HIV-uninfected pregnant women, while selective colonization with more virulent strains in HIV-infected women is suggested in some studies. Lower serotype-specific GBS maternal antibody transfer and quantitative and qualitative defects of innate immune responses in HEU infants may play a role in the increased risk of GBS invasive disease. The impact of maternal antiretroviral treatment and its consequences on immune activation in HEU newborns are important to study. Maternal immunization presents a promising intervention to reduce GBS burden in the growing HEU population.

Slow CD4+ T-Cell Recovery in Human Immunodeficiency Virus/Hepatitis B Virus-Coinfected Patients Initiating Truvada-Based Combination Antiretroviral Therapy in Botswana

Background.  Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) coinfection has emerged as an important cause of morbidity and mortality. We determined the response to Truvada-based first-line combination antiretroviral therapy (cART) in HIV/HBV-coinfected verus HIV-monoinfected patients in Botswana. Methods.  Hepatitis B virus surface antigen (HBsAg), HBV e antigen (HBeAg), and HBV deoxyribonucleic acid (DNA) load were determined from baseline and follow-up visits in a longitudinal cART cohort of Truvada-based regimen. We assessed predictors of HBV serostatus and viral suppression (undetectable HBV DNA) using logistic regression techniques. Results.  Of 300 participants, 28 were HBsAg positive, giving an HIV/HBV prevalence of 9.3% (95% confidence interval [CI], 6.3-13.2), and 5 of these, 17.9% (95% CI, 6.1-36.9), were HBeAg positive. There was a reduced CD4+ T-cell gain in HIV/HBV-coinfected compared with HIV-monoinfected patients. Hepatitis B virus surface antigen and HBeAg loss was 38% and 60%, respectively, at 24 months post-cART initiation. The HBV DNA suppression rates increased with time on cART from 54% to 75% in 6 and 24 months, respectively. Conclusions.  Human immunodeficiency virus/HBV coinfection negatively affected immunologic recovery compared with HIV-1C monoinfection. Hepatitis B virus screening before cART initiation could help improve HBV/HIV treatment outcomes and help determine treatment options when there is a need to switch regimens.

Antibiotic resistance of Streptococcus agalactiae isolated from pregnant women in Garankuwa, South Africa

Background

This study was undertaken to determine the susceptibility profile and the mechanism of antibiotic resistance in Group B streptococcus (GBS) isolates detected in vaginal and rectal swabs from pregnant women attending Dr George Mukhari Academic Hospital, a University Teaching Hospital in Pretoria, South Africa.

Methods

The samples were collected over an 11-month period, cultured on selective media (colistin and nalidixic acid agar and Todd-Hewitt broth), and GBS positively identified by using different morphological and biochemical tests. The susceptibility testing was done using the Kirby–Bauer and E test methods according to CLSI guidelines 2012. The D test method was used for the detection of inducible clindamycin resistance. Multiplex PCR with specific primers was used to detect different genes coding for resistance.

Results

Out of 413 samples collected, 128 (30.9 %) were positive with GBS. The susceptibility testing revealed that 100 % of isolates were sensitive to penicillin, ampicillin, vancomycin and high level gentamicin. Erythromycin and clindamycin resistance was 21.1 and 17.2 %, respectively, in which 69 % had harboured constitutive macrolide, lincosamide and streptogramin B (MLS_B), 17.4 % had inducible MLS_B. The M and L phenotypes were present in 6.8 % each. The methylation of target encoded by ermB genes was the commonest mechanism of resistance observed in 55 % of isolates, 38 % of isolates had both ermB and linB genes and efflux pump mediated by mefA genes was also distributed among the isolates.

Conclusions

The study reaffirmed the appropriateness of penicillin as the antibiotic of choice for treating GBS infection. However it identified the challenges of resistance to macrolides and lincosamides used as alternative drugs for individuals allergic to penicillin. More GBS treatment options for penicillin allergic patients need to be researched on.

Neonatal group B streptococcus disease in developing countries: are we ready to deploy a vaccine?

Group B streptococcus (GBS) disease is the leading cause of neonatal sepsis in developed countries and has high case fatality rates. In developing countries, however, the burden of GBS is less clear; this is due to a lack of studies using optimal diagnostic, clinical and laboratory techniques and is complicated by the wide availability of non-prescription antibiotics to the general population and in peripartum patients. There is an urgent need for prospective, population-based surveillance to provide an accurate assessment of neonatal GBS disease burden in developing countries, which remains largely unrecognized, and consequently obscures the potential relevance of GBS vaccination in these populations. Preliminary data on GBS vaccines are promising as a preventive tool for neonatal GBS infection, more so than any other currently available public health initiative. However, how do we assess the true impact of a GBS vaccine without accurate surveillance data on the real burden of disease?

HIV-1 Is Associated With Lower Group B Streptococcus Capsular and Surface-Protein IgG Antibody Levels and Reduced Transplacental Antibody Transfer in Pregnant Women

BACKGROUND

Human immunodeficiency virus (HIV)-exposed infants are at increased risk of invasive Group B Streptococcus (GBS) disease; however, the reason for this increased susceptibility has not been characterized.

METHODS

We compared GBS capsular and surface-protein maternal immunoglobin G antibody concentrations and cord-maternal ratios between HIV-infected and HIV-uninfected mother-newborn dyads.

RESULTS

Median capsular antibody concentrations (µg/mL) were lower in HIV-infected than HIV-uninfected women for serotypes Ib (P = .033) and V (P = .040); and for pilus island (PI)-1 (P = .016), PI-2a (P = .015), PI-2b (P = .015), and fibrinogen-binding protein A (P < .001). For serotypes Ia and III, cord-maternal ratios were 37.4% (P < .001) and 32.5% (P = .027) lower in HIV-infected compared to HIV-uninfected mother-newborn dyads. The adjusted odds of having capsular antibody concentration ≥2 µg/mL when comparing HIV-infected to -uninfected women were 0.33 (95% confidence interval [CI], .15-.75) and 0.34 (95% CI, .12-1.00) for serotypes Ia and III, respectively. Antibody levels and cord-maternal ratios were independent of CD4(+) lymphocyte counts or HIV-1 viral load.

CONCLUSIONS

The lower GBS antibody concentrations and reduced transplacental antibody transfer in HIV-infected women, which likely contribute to their infants being at heightened susceptibility for invasive GBS disease, could possibly be mitigated by vaccination with a GBS conjugate vaccine currently under clinical development.

Contemporary management of human immunodeficiency virus in pregnancy

Contemporary management of HIV in pregnancy remains a moving target. With the development of newer antiretroviral agents with lower side-effect profiles and laboratory methods for detection and monitoring of HIV, considerable progress has been made. This review examines key concepts in the pathophysiology of HIV and pregnancy with emphasis on perinatal transmission and reviews appropriate screening and diagnostic testing for HIV during pregnancy. Current recommendations for medical, pharmacologic, and obstetric management of women newly diagnosed with HIV during pregnancy and for those women with preexisting infection are discussed. Preconception counseling for HIV+ women as well as postpartum issues are addressed.

Epidemiology and impact of HIV coinfection with hepatitis B and hepatitis C viruses in Sub-Saharan Africa

Human immunodeficiency virus (HIV), Hepatitis B (HBV) and Hepatitis C (HCV) are blood-borne viruses with potentially shared routes of transmission. In high-income settings, the impact of antiretroviral therapy (ART) on survival has unmasked chronic liver disease from viral hepatitis B or hepatitis C as a leading cause of morbidity and mortality in individuals with HIV infection. It is now feared that progressive liver disease may threaten the success of ART programmes in developing countries, where HCV or HBV testing and monitoring are not yet systematic among HIV-infected patients and ART use is generally blind to these co-infections. We set out to review recent data from Sub-Saharan Africa, in order to build a detailed and up-to-date picture of the epidemiology and emerging impact of HBV and HCV coinfection in countries at the heart of the HIV pandemic. There is a preponderance of HIV/HBV coinfection compared to HIV/HCV in this region, and significant caveats exist regarding the accuracy of published HCV seroprevalence surveys. Morbidity and mortality of coinfection is significant, and may be further enhanced in African populations due to the influence of host, viral and environmental factors. Careful scrutiny of the coinfection problem is vital to inform an approach to directing resources, planning public health initiatives, providing clinical care, and guiding future research.

Institutional prevention policies and rates of Group B Streptococcus infection among HIV-infected pregnant women and their infants in Latin America

OBJECTIVE

To describe Group B Streptococcus (GBS) prevention policies at 12 Latin American sites participating in the NICHD (Eunice Kennedy Shriver National Institute of Child Health and Human Development) International Site Development Initiative (NISDI) Longitudinal Study in Latin American Countries (LILAC) and to determine rates of rectovaginal colonization and GBS-related disease among HIV-infected pregnant women and their infants.

METHODS

Site surveys were used to assess prevention policies and practices administered cross-sectionally during 2010. Data collected in NISDI from 2008 to 2010 regarding HIV-infected pregnant women were used to determine rates of colonization and GBS-related disease.

RESULTS

Of the 9 sites with a GBS prevention policy, 7 performed routine rectovaginal screening for GBS. Of the 401 women included in the NISDI study, 56.9% were at sites that screened. The GBS colonization rate was 8.3% (19/228 women; 95% confidence interval [CI], 5.1%-12.7%). Disease related to GBS occurred in 0.5% of the participants (2/401 women; 95% CI, 0.1%-1.8%); however, no GBS-related disease was reported among the 398 infants (95% CI, 0.0%-0.9%).

CONCLUSION

Improved efforts to implement prevention policies and continued surveillance for GBS are needed to understand the impact of GBS among HIV-infected pregnant women and their infants in Latin America.

Bacteraemia in Malawian neonates and young infants 2002-2007: a retrospective audit

OBJECTIVES

To assess the causes of bacteraemia in young infants and susceptibility to first-line antibiotics (benzylpenicillin plus gentamicin) at the Queen Elizabeth Central Hospital (QECH), Malawi during 2002-2007.

DESIGN

Retrospective analysis of demographic and microbiological data using laboratory records.

SETTING

QECH is Malawi's largest hospital with 7000 neonates admitted annually, 9% for septicaemia.

PATIENTS

All infants aged 60 days or less admitted to QECH that had a blood culture taken over the 6-year period.

MAIN OUTCOME MEASURES

6754 blood cultures were taken. 3323 organisms were isolated: one-third were pathogens, two-thirds contaminants. Gram-positive organisms (53%) were more common than gram-negatives (47%). Four organisms made up half of all pathogens: Staphylococcus aureus (15.3%), group B streptococci (13.5%), non-typhoidal salmonellae (12.6%) and Escherichia coli (10.5%). Apart from non-typhoidal salmonellae and Streptococcus pneumoniae, most organisms were more common in the first week of life than later. Overall, 28% of isolates during 2002-2007 were resistant to first-line antibiotic, higher than observed during 1996-2001 (22%). Penicillin susceptibility fluctuated while gram-negative resistance to gentamicin increased from 17% to 27% over the study period.

CONCLUSIONS

In the QECH, pathogens causing young infant sepsis are an unusual mix of organisms seen in both developed and developing countries. Resistance to first-line antibiotics is higher than observed in most studies. Ongoing monitoring is needed and clinical outcome data would aid interpretation of findings. A high proportion of blood cultures were contaminated with skin flora-improved training and supervision of phlebotomists are needed to improve the utility of taking blood cultures.

Group B Streptococcus colonization by HIV status in pregnant women: prevalence and risk factors

OBJECTIVES

To examine the prevalence of and risk factors for group B Streptococcus (GBS) colonization in an HIV-infected and uninfected pregnant population.

METHODS

We conducted a retrospective double cohort study comparing the prevalence of GBS colonization between 90 HIV-infected and 1947 uninfected women attending prenatal care at San Francisco General Hospital, an urban public hospital affiliated with the University of California, San Francisco. We investigated risk factors for GBS colonization, including age, ethnicity, obesity, diabetes, alcohol or illicit drug use, tobacco use, degree of immunosuppression, and infectious comorbidities.

RESULTS

In the multivariable analysis, HIV serostatus was not independently associated with GBS colonization (odds ratio [OR] 1.00, 95% confidence interval [CI] 0.62-1.62). Obesity (OR 1.53, 95% CI 1.13-2.07), white race (OR 1.89, 95% CI 1.30-2.75), and black race (OR 1.78, 95% CI 1.32-2.41) were independently associated with increased maternal GBS colonization. Among HIV-infected women, univariate analysis showed an association between GBS colonization and detectable HIV-1 plasma viral load at the time of rectovaginal culture (p<0.05). Mean CD4 lymphocyte count, infectious comorbidities, and HIV-1 plasma viral load at delivery were not associated with GBS colonization in HIV-infected pregnant women.

CONCLUSIONS

HIV-1 infection is not a risk factor for GBS colonization among an ethnically diverse pregnant population at San Francisco General Hospital, although our data suggest that among HIV-infected women, plasma HIV-1 viremia may be associated with GBS colonization. Interventions that diminish HIV-1 plasma viral load and, perhaps, genital tract shedding of HIV may be associated with a reduced risk of GBS colonization in future studies.

Group B Streptococcus in a cohort of HIV-infected pregnant women: prevalence of colonization, identification and antimicrobial susceptibility profile

Group B Streptococcus (GBS) is a leading cause of infectious morbidity in newborns. We describe the prevalence of GBS colonization and the serotypes and antibiotic susceptibility profiles of isolates obtained from a cohort of human immunodeficiency virus (HIV)-infected pregnant women. This was a cross-sectional study at a centre for the prevention of mother-to-child transmission of HIV. Vaginal and rectal swabs were collected at 35-37 weeks of gestation from 158 eligible women. GBS isolates were serotyped and antimicrobial susceptibility tests performed. Patient sociodemographic characteristics, CD4 counts and viral loads were abstracted from records. The overall anogenital prevalence of GBS colonization was 49/158 (31.0%): 40/158 (25.3%) for vagina, 19/158 (12.0%) for rectum and 10/158 (6.3%) for both. Predominant serotypes were Ib (34.9%) and Ia (25.6%). All were penicillin-susceptible. Two were resistant to erythromycin (4.0%) and one to clindamycin (2.0%). The colonization rate by GBS was high in this cohort. Serotype Ib was the most frequently identified.