Cost-effectiveness of maternal GBS immunization in low-income sub-Saharan Africa

Maternal Immunizations: Past, Present, and Future

Maternal vaccines during pregnancy offer crucial protection against infections for both the pregnant person and their newborn. Vaccines against influenza, pertussis, coronavirus disease 2019, and respiratory syncytial virus are routinely recommended by the Centers for Disease Control and Prevention to safeguard pregnant women and their infants from potentially severe complications. Administering these vaccines during pregnancy helps transfer protective antibodies from the mother to the baby, enhancing immunity during the vulnerable early months of life. Extensive research supports the safety and efficacy of maternal vaccines, with numerous studies demonstrating their protective benefits for both pregnant people and newborns.

Interventions to Improve Knowledge, Attitudes, and Uptake of Recommended Vaccines during Pregnancy and Postpartum: A Scoping Review

Tetanus, pertussis, influenza, and COVID-19 vaccines are recommended for the prevention of related morbidity and mortality during pregnancy and postpartum. Despite the established benefits of vaccination for prenatal and postnatal women, maternal vaccination is not universally included in routine antenatal programs, especially in low- and middle-income countries. Furthermore, the uptake of recommended vaccines among pregnant and postpartum women remains below optimum globally. This review aimed to map the evidence on interventions to improve knowledge, attitudes, and uptake of recommended vaccines among pregnant and postpartum women. We conducted a comprehensive and systematic search for relevant literature in PubMed, Scopus, Web of Science, EBSCOhost, and Google Scholar. Overall, 29 studies published between 2010 and 2023 were included in this review. The majority (n = 27) of these studies were from high-income countries. A total of 14 studies focused on the influenza vaccine, 6 on the Tdap vaccine, 8 on both influenza and Tdap vaccines, and only one study on the COVID-19 vaccine. Patient-centered interventions predominated the evidence base (66%), followed by provider-focused (7%), health system-focused (10%), and multilevel interventions (17%). Overall, the effect of these interventions on knowledge, attitudes, and uptake of maternal vaccines was variable.

Vaccine value profile for Group B streptococcus

Group B streptococcus (GBS) is a major global cause of neonatal meningitis, sepsis and pneumonia, with an estimated 91,000 infant deaths per year and an additional 46,000 stillbirths. GBS infection in pregnancy is also associated with adverse maternal outcomes and preterm births. As such, the World Health Organization (WHO) prioritised the development of a GBS vaccine suitable for use in pregnant women and use in LMICs, where the burden of disease is highest. Several GBS vaccines are in clinical development. The WHO Defeating Meningitis by 2030 has set a target of 2026 for vaccine licensure. This 'Vaccine Value Profile' (VVP) for GBS is intended to provide a high-level, holistic assessment of the information and data that are currently available to inform the potential public health, economic and societal value of pipeline vaccines and vaccine-like products. This VVP was developed by a working group of subject matter experts from academia, non-profit organizations, public private partnerships and multi-lateral organizations, and in collaboration with stakeholders from the WHO regions of AFR, AMR, EUR, WPR. All contributors have extensive expertise on various elements of the GBS VVP and collectively aimed to identify current research and knowledge gaps. The VVP was developed using only existing and publicly available information.

Cost-effectiveness analysis of maternal vaccination against Group B streptococcus in Japan

Background

Group B Streptococcus (GBS) is a leading pathogen causing life-threatening bacterial infections in neonates (early- or late-onset) and infants, and is associated with preterm and stillbirth. Japan introduced national guidelines to reduce early-onset neonatal GBS disease, with universal prenatal screening and intrapartum antimicrobial prophylaxis (IAP). However, screening/IAP does not prevent GBS associated late-onset disease, preterm or stillbirth. Maternal GBS vaccines in development are targeted at infant GBS disease but may provide benefit across perinatal outcomes. We aimed to assess cost-effectiveness of a future maternal GBS vaccine, for a base case prevention of infant GBS disease in combination with screening/IAP compared to screening/IAP alone.

Methods

We used a decision tree model to estimate cases of infant GBS disease, deaths, and neuro-developmental impairment (NDI), GBS-related stillbirths, and the associated costs and loss in Quality-Adjusted Life Years (QALYs). We calculate the threshold price at which a vaccine would be cost-effective assuming a cost-effectiveness threshold of ¥5 million/QALY. We explored the potential benefit of a maternal GBS vaccine that also prevents preterm birth in a scenario analysis.

Results

Maternal GBS vaccination in Japan could prevent an additional 142 infant GBS cases annually, including 5 deaths and 21 cases of NDI, and 13 stillbirths compared to screening/IAP alone. The incremental cost-effectiveness ratio (ICER) was ¥3.78 million/QALY with a vaccine cost of ¥5,000/dose. If the QALY lost for stillbirth is included, the ICER is reduced to ¥1.78 million/QALY. Median threshold vaccine price was ¥6,900 per dose (95 % uncertainty interval ¥5,100 to ¥9,200 per dose). If maternal GBS vaccination also prevented half of GBS-associated preterm, the ICER would be reduced to ¥1.88 million/QALY.

Conclusions

An effective maternal GBS vaccine is likely to be considered cost-effective in Japan at a price of ¥5,000/dose. Effectiveness against other adverse perinatal outcomes would increase health benefits and cost-effectiveness.

Early-onset group B streptococcal disease in African countries and maternal vaccination strategies

Invasive group B streptococcal (GBS) disease is the commonest perinatally-acquired bacterial infection in newborns; the burden is higher in African countries where intrapartum antibiotic prophylaxis strategies are not feasible. In sub-Saharan Africa, almost one in four newborns with GBS early-onset disease will demise, and one in ten survivors have moderate or severe neurodevelopmental impairment. A maternal GBS vaccine to prevent invasive GBS disease in infancy is a pragmatic and cost-effective preventative strategy for Africa. Hexavalent polysaccharide protein conjugate and Alpha family surface protein vaccines are undergoing phase II clinical trials. Vaccine licensure may be facilitated by demonstrating safety and immunological correlates/thresholds suggestive of protection against invasive GBS disease. This will then be followed by phase IV effectiveness studies to assess the burden of GBS vaccine preventable disease, including the effect on all-cause neonatal infections, neonatal deaths and stillbirths.

Maternity care provider acceptance of a future Group B Streptococcus vaccine - A qualitative study in three countries

INTRODUCTION

There are vaccines in clinical trials that target the bacterium Group B Streptococcus (GBS). When approved, GBS vaccines will be intended for administration to pregnant women to prevent infection in their infants. The success of any vaccine will depend on its' uptake in the population. Experience with prior maternal vaccines, e.g. influenza, Tdap and COVID-19 vaccines, teaches us that acceptance of vaccines, especially if novel, is challenging for pregnant women, and that provider recommendation is a key driver of vaccine uptake.

METHODS

This study investigated attitudes of maternity care providers towards the introduction of a GBS vaccine in three countries (the United States (US), Ireland, and the Dominican Republic (DR)) with different GBS prevalence and prevention practices. Semi-structured interviews with maternity care providers were transcribed and coded for themes. The constant comparative method, and inductive theory building were used to develop conclusions.

RESULTS

Thirty-eight obstetricians, 18 general practitioners and 14 midwives participated. There was variability in provider attitudes towards a hypothetical GBS vaccine. Responses ranged from enthusiasm to doubts over the need for a vaccine. Attitudes were influenced by perceived additional benefits of a vaccine over current strategy and confidence in the safety of vaccines during pregnancy. Knowledge, experience and approaches to GBS prevention differed geographically and according to provider type, and influenced how participants assessed the risks and benefits of a GBS vaccine.

CONCLUSION

Maternity care providers are engaged in the topic of GBS management and there is opportunity to leverage attitudes and beliefs that will support a strong recommendation for a GBS vaccine. However, knowledge of GBS, and of the limitations of current prevention strategies vary among providers in different regions, and between different provider types. Targeted educational efforts with antenatal providers should focus on highlighting safety data the potential benefits of vaccination over current strategies.

Maternal immunisation against Group B Streptococcus: A global analysis of health impact and cost-effectiveness

BACKGROUND

Group B Streptococcus (GBS) can cause invasive disease (iGBS) in young infants, typically presenting as sepsis or meningitis, and is also associated with stillbirth and preterm birth. GBS vaccines are under development, but their potential health impact and cost-effectiveness have not been assessed globally.

METHODS AND FINDINGS

We assessed the health impact and value (using net monetary benefit (NMB), which measures both health and economic effects of vaccination into monetary units) of GBS maternal vaccination in an annual cohort of 140 million pregnant women across 183 countries in 2020. Our analysis uses a decision tree model, incorporating risks of GBS-related health outcomes from an existing Bayesian disease burden model. We extrapolated country-specific GBS-related healthcare costs using data from a previous systematic review and calculated quality-adjusted life years (QALYs) lost due to infant mortality and long-term disability. We assumed 80% vaccine efficacy against iGBS and stillbirth, following the WHO Preferred Product Characteristics, and coverage based on the proportion of pregnant women receiving at least 4 antenatal visits. One dose was assumed to cost $50 in high-income countries, $15 in upper-middle income countries, and $3.50 in low-/lower-middle-income countries. We estimated NMB using alternative normative assumptions that may be adopted by policymakers. Vaccinating pregnant women could avert 127,000 (95% uncertainty range 63,300 to 248,000) early-onset and 87,300 (38,100 to 209,000) late-onset infant iGBS cases, 31,100 deaths (14,400 to 66,400), 17,900 (6,380 to 49,900) cases of moderate and severe neurodevelopmental impairment, and 23,000 (10,000 to 56,400) stillbirths. A vaccine effective against GBS-associated prematurity might also avert 185,000 (13,500 to 407,000) preterm births. Globally, a 1-dose vaccine programme could cost $1.7 billion but save $385 million in healthcare costs. Estimated global NMB ranged from $1.1 billion ($-0.2 to 3.8 billion) under the least favourable normative assumptions to $17 billion ($9.1 to 31 billion) under the most favourable normative assumptions. The main limitation of our analysis was the scarcity of data to inform some of the model parameters such as those governing health-related quality of life and long-term costs from disability, and how these parameters may vary across country contexts.

CONCLUSIONS

In this study, we found that maternal GBS vaccination could have a large impact on infant morbidity and mortality. Globally, a GBS maternal vaccine at reasonable prices is likely to be a cost-effective intervention.

Advances towards licensure of a maternal vaccine for the prevention of invasive group B streptococcus disease in infants: a discussion of different approaches

Group B streptococcus (Streptococcus agalactiae, GBS) is an important cause of life-threatening disease in newborns. Pregnant women colonized with GBS can transmit the bacteria to the developing fetus, as well as to their neonates during or after delivery where infection can lead to sepsis, meningitis, pneumonia, or/and death. While intrapartum antibiotic prophylaxis (IAP) is the standard of care for prevention of invasive GBS disease in some countries, even in such settings a substantial residual burden of disease remains. A GBS vaccine administered during pregnancy could potentially address this important unmet medical need and provide an adjunct or alternative to IAP for the prevention of invasive GBS disease in neonates. A hurdle for vaccine development has been relatively low disease rates making efficacy studies difficult. Given the well-accepted inverse relationship between anti-GBS capsular polysaccharide antibody titers at birth and risk of disease, licensure using serological criteria as a surrogate biomarker represents a promising approach to accelerate the availability of a GBS vaccine.

Molecular Epidemiology of Group B Streptococcus Colonization in Egyptian Women

(1) Background: Streptococcus agalactiae or Group B Streptococcus (GBS) causes severe neonatal infections with a high burden of disease, especially in Africa. Maternal vaginal colonization and perinatal transmissions represent the common mode of acquiring the infection. Development of an effective maternal vaccine against GBS relies on molecular surveillance of the maternal GBS population to better understand the global distribution of GBS clones and serotypes. (2) Methods: Here, we present genomic data from a collection of colonizing GBS strains from Ismailia, Egypt that were sequenced and characterized within the global JUNO project. (3) Results: A large proportion of serotype VI, ST14 strains was discovered, a serotype which is rarely found in strain collections from the US and Europe and typically not included in the current vaccine formulations. (4) Conclusions: The molecular epidemiology of these strains clearly points to the African origin with the detection of several sequence types (STs) that have only been observed in Africa. Our data underline the importance of continuous molecular surveillance of the GBS population for future vaccine implementations.

Group B Streptococcal Colonization in African Countries: Prevalence, Capsular Serotypes, and Molecular Sequence Types

Streptococcus agalactiae or group B streptococcus (GBS) is a commensal of the gastrointestinal and genitourinary tracts of healthy women and an important cause of neonatal invasive infections worldwide. Transmission of bacteria to the newborn occurs at birth and can be prevented by intrapartum antibiotic prophylaxis. However, this not available in resource limited settings in Africa, which carries a particular high burden of disease. Serotype based vaccines are in development and present a suitable alternative to prevent neonatal infections. To be able to assess vaccine efficacy, knowledge and surveillance of GBS epidemiological data are required. This review summarizes investigations about the serotype distribution and the multi-locus sequence types (MLST) found in different African countries. While most serotypes and MLST data are comparable to findings from other continents, some specific differences exist. Serotype V is predominant among colonizing maternal strains in many different African countries. Serotypes that are rarely detected in western industrialized nations, such as serotypes VI, VII and IX, are prevalent in studies from Ghana and Egypt. Moreover, some specific MLST sequence types that seem to be more or less unique to Africa have been detected. However, overall, the data confirm that a hexavalent vaccine can provide broad coverage for the African continent and that a protein vaccine could represent a promising alternative.

Comparison of static and dynamic models of maternal immunization to prevent infant pertussis in Brazil

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Dynamic transmission models of infectious disease capture the herd immunity effects of vaccination.

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We compared dynamic and static models of maternal acellular pertussis (aP) immunization built with Brazilian data.

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At infant vaccine coverage < 90–95%, both models estimate that maternal immunization is cost-effective.

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Only the dynamic model shows that maternal immunization is not cost-effective at infant coverage > 90–95%.

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The background effect of routine infant vaccination is critical to the cost-effectiveness of maternal aP immunization.

Background

This paper compares cost-effectiveness results from two models of maternal immunization to prevent pertussis in infants in Brazil, one static, one dynamic, to explore when static models are adequate for public health decisions and when the extra effort required by dynamic models is worthwhile.

Methods

We defined two scenarios to explore key differences between static and dynamic models, herd immunity and time horizon. Scenario 1 evaluates the incremental cost/DALY of maternal acellular pertussis (aP) immunization as routine infant vaccination coverage ranges from low/moderate up to, and above, the threshold at which herd immunity begins to eliminate pertussis. Scenario 2 compares cost-effectiveness estimates over the models’ different time horizons. Maternal vaccine prices of $9.55/dose (base case) and $1/dose were evaluated.

Results

The dynamic model shows that maternal immunization could be cost-saving as well as life-saving at low levels of infant vaccination coverage. When infant coverage reaches the threshold range (90–95%), it is expensive: the dynamic model estimates that maternal immunization costs $2 million/DALY at infant coverage > 95% and maternal vaccine price of $9.55/dose; at $1/dose, cost/DALY is $200,000. By contrast, the static model estimates costs/DALY only modestly higher at high than at low infant coverage. When the models’ estimates over their different time horizons are compared at infant coverage < 90–95%, their projections fall in the same range.

Conclusions

Static models may serve to explore an intervention’s cost-effectiveness against infectious disease: the direction and principal drivers of change were the same in both models. When, however, an intervention too small to have significant herd immunity effects itself, such as maternal aP immunization, takes place against a background of vaccination in the rest of the population, a dynamic model is crucial to accurate estimates of cost-effectiveness. This finding is particularly important in the context of widely varying routine infant vaccination rates globally.

Clinical Trial registry

Clinical Trial registry name and registration number: Not applicable.

Cost-effectiveness of maternal immunization against neonatal invasive Group B Streptococcus in the Netherlands

BACKGROUND

Neonatal invasive Group B Streptococcus (GBS) infection causes considerable disease burden in the Netherlands. Intrapartum antibiotic prophylaxis (IAP) prevents early-onset disease (EOD), but has no effect on late-onset disease (LOD). A potential maternal GBS vaccine could prevent both EOD and LOD by conferring immunity in neonates.

OBJECTIVE

Explore under which circumstances maternal vaccination against GBS would be cost-effective as an addition to, or replacement for the current risk factor-based IAP prevention strategy in the Netherlands.

METHODS

We assessed the maximum cost-effective price per dose of a trivalent (serotypes Ia, Ib, and III) and hexavalent (additional serotypes II, IV, and V) GBS vaccine in addition to, or as a replacement for IAP. To project the prevented costs and disease burden, a decision tree model was developed to reflect neonatal GBS disease and long-term health outcomes among a cohort based on 169,836 live births in the Netherlands in 2017.

RESULTS

Under base-case conditions, maternal immunization with a trivalent vaccine would gain 186 QALYs and prevent more than €3.1 million in health care costs when implemented in addition to IAP. Immunization implemented as a replacement for IAP would gain 88 QALYs compared to the current prevention strategy, prevent €1.5 million in health care costs, and avoid potentially ~ 30,000 IAP administrations. The base-case results correspond to a maximum price of €58 per dose (vaccine + administration costs; using a threshold of €20,000/QALY). Expanding the serotype coverage to a hexavalent vaccine would only have a limited additional impact on the cost-effectiveness in the Netherlands.

CONCLUSIONS

A maternal GBS vaccine could be cost-effective when implemented in addition to the current risk factor-based IAP prevention strategy in the Netherlands. Discontinuation of IAP would save costs and prevent antibiotic use, however, is projected to lead to a lower health gain compared to vaccination in addition to IAP.

The Association Between Breast Milk Group B Streptococcal Capsular Antibody Levels and Late-onset Disease in Young Infants

BACKGROUND

Animal-model studies have demonstrated less group B streptococcal (GBS) invasive disease and gastrointestinal colonization after enteral administration of serotype-specific capsular antibodies. There is, however, a paucity of information on the association of breast milk GBS serotype-specific capsular antibodies and risks for invasive disease in infants. The aim of this study was to explore the association between natural secretory immunoglobulin A (sIgA) capsular antibodies in breast milk and the occurrence of late-onset disease (LOD) in young infants.

METHODS

A matched case-control study was undertaken in infants <3 months of age in Johannesburg, South Africa. Breast milk samples were collected on cases and controls matched for gestational age, maternal age, and human immunodeficiency virus status at time of enrollment. Capsular serotype Ia, Ib, III, and V sIgA antibody concentrations were measured using the fluorescence-based micro-bead immunosorbent assay.

RESULTS

Breast milk samples were available for 31 LOD cases (8 serotype Ia and 23 serotype III), 21 recto-vaginally colonized matched controls (10 serotype Ia and 11 serotype III), and 84 serotype Ia and 105 serotype III noncolonized matched controls. Using a Bayesian model to estimate the probability of disease, there were 90% reductions in the risks of developing serotypes Ia and III LOD with sIgA concentrations ≥0.14 µg/mL and ≥2.52 µg/mL, respectively.

CONCLUSIONS

Breast milk sIgA capsular antibodies were associated with lower risks for LOD in young infants. The ability of GBS polysaccharide-protein conjugate vaccines currently under development to induce sIgA responses warrant investigation as potential mediators of protection against LOD.

Seroepidemiology of maternally-derived antibody against Group B Streptococcus (GBS) in Mulago/Kawempe Hospitals Uganda - PROGRESS GBS

Background: Group B Streptococcus (GBS) is a major contributor to the high burden of neonatal and young infant infectious disease in resource- limited settings. As disease protection during the first six months of life is provided via placental transfer of maternal antibodies, a maternal GBS vaccine may provide an effective strategy to reduce infectious death and disability. An efficacy study may be difficult because of the large sample size required and alternative approaches such as serocorrelates of protection based on natural antibody concentration are being considered. Such studies would need to be undertaken in high burden settings such as Uganda. We therefore aim to evaluate the feasibility and acceptability of a GBS sero-epidemiology study in Kampala, Uganda.

Methods: This is a prospective cohort and nested case-control study, conducted across two-centres with two entry points. A) consecutive women and their infants at birth, with collection of maternal swab, cord and maternal blood, and follow up by telephone until the infant is 3 months old; B) any infant under 3 months of age, presenting with signs of sepsis to any of the paediatric units, with collection of blood culture, cerebrospinal fluid and nasopharyngeal swabs. Any infants identified as having GBS disease (defined as GBS isolated from a normally sterile site) will be recruited and followed up for two years to assess their neurodevelopment. A nested qualitative study will investigate stakeholder (pregnant women and their families, healthcare workers and community leaders) opinions of sampling for such a study and understanding and potential uptake of vaccines in pregnancy.

Discussion: The primary aim is to determine anti-GBS antibody concentration in infants with GBS disease compared to healthy controls. Secondary outcomes include stillbirth and all-cause infection and acceptance of sample methods and vaccination. The findings will inform scalability and sustainability of the programme in Uganda.

Differences in maternal group B Streptococcus screening rates in Latin American countries

OBJECTIVE

To determine rates and results of maternal Group B streptococcus (GBS) screening during pregnancy and identify sociodemographic characteristics associated with GBS screening in Latin American countries.

BACKGROUND

GBS is a primary cause of morbidity and mortality in neonates and is prevented by screening pregnant women for GBS before delivery and intrapartum antibiotic treatment. Yet, data regarding national GBS screening practices and the epidemiology of maternal GBS colonization in Latin America are limited.

METHODS

We conducted a retrospective observational study using de-identified records of pregnant women in six Latin American countries from a regional database. 460,328 collected from January 1, 2009 through December 31, 2012 met study criteria and were included. Maternal screening rates for GBS were determined, association of demographic variables (ethnicity, age, education level, and civil status) with maternal GBS screening was determined using logistic regression, odds ratios were calculated comparing incidence of adverse neonatal outcomes (sepsis, pneumonia, and meningitis) between countries with high and low rates of GBS screening, maternal GBS colonization prevalence was determined by year and association of demographic variables with maternal GBS colonization was determined using logistic regression.

RESULTS

Maternal GBS screening was less than 15% in each country, except Uruguay which screened greater than 65% of women. The final regression model examining maternal screening rates and demographic variables included the covariates ethnicity, maternal age group, education level and civil status. Countries with lower rates of maternal GBS screening had increased odds of neonatal sepsis [OR 23.3; 95% CI (15.2-35.9)] and pneumonia [OR 19.9; 95% CI (12.1-32.6)]. In Uruguay, GBS prevalence over the study period was 18.5%. Black women, older women and women without a primary education had higher rates of GBS colonization (21.3%, 20.4% and 21.9% respectively).

CONCLUSIONS

Our study highlights the need for national policy and investments to increase maternal GBS screening and better understand the prevalence of maternal GBS colonization in Latin America. Further research on the burden of neonatal GBS disease within Latin America is needed to inform the introduction of a maternal GBS vaccine, when available.

Seroepidemiology of maternally-derived antibody against Group B Streptococcus (GBS) in Mulago/Kawempe Hospitals Uganda - PROGRESS GBS

Background: Group B Streptococcus (GBS) is a major contributor to the high burden of neonatal and young infant infectious disease in resource- limited settings. As disease protection during the first six months of life is provided via placental transfer of maternal antibodies, a maternal GBS vaccine may provide an effective strategy to reduce infectious death and disability. An efficacy study may be difficult because of the large sample size required and alternative approaches such as serocorrelates of protection based on natural antibody concentration are being considered. Such studies would need to be undertaken in high burden settings such as Uganda. We therefore aim to evaluate the feasibility and acceptability of a GBS sero-epidemiology study in Kampala, Uganda. Methods: This is a prospective cohort and nested case-control study, conducted across two-centres with two entry points. A) consecutive women and their infants at birth, with collection of maternal swab, cord and maternal blood, and follow up by telephone until the infant is 3 months old; B) any infant under 3 months of age, presenting with signs of sepsis to any of the paediatric units, with collection of blood culture, cerebrospinal fluid and nasopharyngeal swabs. Any infants identified as having GBS disease (defined as GBS isolated from a normally sterile site) will be recruited and followed up for two years to assess their neurodevelopment. A nested qualitative study will investigate stakeholder (pregnant women and their families, healthcare workers and community leaders) opinions of sampling for such a study and understanding and potential uptake of vaccines in pregnancy. Discussion: The primary aim is to determine anti-GBS antibody concentration in infants with GBS disease compared to healthy controls. Secondary outcomes include stillbirth and all-cause infection and acceptance of sample methods and vaccination. The findings will inform scalability and sustainability of the programme in Uganda.

Assessing the capacity of Ghana to introduce health technology assessment: a systematic review of economic evaluations conducted in Ghana

OBJECTIVES

Ghana is in the process of formally introducing health technology assessment (HTA) for health decision making. Similar to other low- and middle-income countries, evidence suggests that the lack of data and human capacity is a major barrier to the conduct and use of HTA. This study assessed the current human and data capacity available in Ghana to undertake HTA.

METHODS

As economic evaluation (EE) forms an integral part of HTA, a systematic review of EE studies undertaken in Ghana was conducted to identify the quality and number of studies available, methods and source of data used, and local persons involved. The literature search was undertaken in EMBASE (including MEDLINE), PUBMED, and Google Scholar. The quality of studies was evaluated using the Consolidated Health Economics Evaluation Reporting Standards. The number of local Ghanaians who contributed to authorship were used as a proxy for assessing human capacity for HTA.

RESULTS

Thirty-one studies were included in the final review. Overall, studies were of good quality. Studies derived their effectiveness, resource utilization and cost data mainly from Ghana. The most common source of cost data was from the National Health Insurance Scheme pricing list for medicines and tariffs. Effectiveness data were mostly derived from either single study or intervention programs. Sixty out of 199 authors were Ghanaians (30 percent); these authors were mostly involved in data collection and study conceptualization.

CONCLUSIONS

Human capacity for HTA in Ghana is limited. To introduce HTA successfully in Ghana, policy makers would need to develop more local capacity to undertake Ghanaian-specific HTA.

To screen or not to screen women for Group B Streptococcus (Streptococcus agalactiae) to prevent early onset sepsis in newborns: recent advances in the unresolved debate

Streptococcus agalactiae, also known as Group B streptococcus (GBS) is the commonest cause of early onset sepsis in newborns in developed high-income countries. Intrapartum antimicrobial (antibiotic) prophylaxis (IAP) is recognized to be highly effective in preventing early onset Group B sepsis (EOGBS) in newborns. The key controversy is about the strategy that should be used to identify mothers who should receive IAP. There are two strategies that are followed in developed countries: screening-based or risk-factor-based identification of women requiring IAP. The debate regarding which of the two approaches is better has intensified in the recent years with concerns about antimicrobial resistance, effect on newborn’s microbiome and other adverse effects. In this review, we have discussed some of the key research papers published in the period 2015–2019 that have addressed the relative merits and disadvantages of screening versus risk-factor-based identification of women requiring IAP. Although screening-based IAP appears to be more efficacious than risk-based IAP, IAP-based prevention has several limitations including ineffectiveness in prevention of late-onset GBS infection in babies, premature and still births, impact of IAP on neonatal microbiota, emergence of antimicrobial resistance and difficulties in implementing IAP-based strategies in middle and low income countries. Alternative strategies, principally maternal immunization against GBS would circumvent use of IAP. However, no licensed vaccines are currently available for use.

Preparing to introduce new maternal immunizations in low- and lower-middle-income countries: A report from the Bill & Melinda Gates Foundation convening "Allies in Maternal and Newborn Care"; May 3-4, 2018

New strategies will be critical to reduce infant mortality and severe morbidity - there are still 5.2 million newborn deaths and stillbirths each year. The decline in newborn mortality has not kept pace with the reduction in under-five deaths and is slowest in low- and lower-middle-income countries (LMICs). Maternal immunization is a promising intervention to protect infants when they are most vulnerable - in utero and their first few months of life, before they can receive their own vaccines. Successfully introducing new vaccines for pregnant women in LMICs will require collaboration between two fields - (1) immunization and (2) maternal, newborn and child health - that use different service delivery approaches, operate under different policy and funding paradigms, and are not always integrated. In May 2018, stakeholders from these distinct communities convened to identify challenges and opportunities associated with delivering new maternal immunizations. Participants agreed that antenatal care is a logical platform. However, in many resource-constrained settings, antenatal care providers are already overburdened, and most women do not receive the recommended number of antenatal visits. Implementing maternal immunization could help increase antenatal care attendance by offering an additional safe and effective intervention that women value. Substantial effort is needed to demonstrate the benefits of maternal immunization to decision-makers and providers, and to ensure that countries and health systems are ready for introduction. To that end, participants identified the following priorities: assure coherence of policies for introducing new vaccines for pregnant women and strengthen maternal health interventions; generate demand for existing, recommended, and new maternal vaccines; conduct socio-behavioral, health systems and implementation research to shape optimal vaccine delivery strategies; and strengthen antenatal and perinatal care quality. To achieve these aims, collaboration across fields will be essential. Given that new maternal vaccines are advancing in clinical development, time is of the essence.

A Vaccine Against Group B Streptococcus: Recent Advances

Group B streptococcus (GBS) causes a high burden of neonatal and infant disease globally. Implementing a vaccine for pregnant women is a promising strategy to prevent neonatal and infant GBS disease and has been identified as a priority by the World Health Organisation (WHO). GBS serotype-specific polysaccharide – protein conjugate vaccines are at advanced stages of development, but a large number of participants would be required to undertake Phase III clinical efficacy trials. Efforts are therefore currently focused on establishing serocorrelates of protection in natural immunity studies as an alternative pathway for licensure of a GBS vaccine, followed by Phase IV studies to evaluate safety and effectiveness. Protein vaccines are in earlier stages of development but are highly promising as they might confer protection irrespective of serotype. Further epidemiological, immunological and health economic studies are required to enable the vaccine to reach its target population as soon as possible.

Potential cost-effectiveness of a maternal Group B streptococcal vaccine in The Gambia

OBJECTIVE

To estimate neonatal health benefits and healthcare provider costs of a theoretical Group B streptococcal (GBS) hexavalent maternal vaccination programme in The Gambia, a low-income setting in West Africa.

METHODS

A static decision analytic cost-effectiveness model was developed from the healthcare provider perspective. Demographic data and acute care costs were available from studies in The Gambia undertaken in 2012-2015. Further model parameters were taken from United Nations and World Health Organisation sources, supplemented by data from a global systematic review of GBS and literature searches. As vaccine efficacy is not known, we simulated vaccine efficacy estimates of 50-90%. Costs are reported in US dollars. Cost-effectiveness thresholds of one (US$473, very cost effective) and three (US$1420, cost effective) times Gambian GDP were used.

RESULTS

Vaccination with a hexavalent vaccine would avert 24 GBS disease cases (55%) and 768 disability adjusted life years compared to current standard of care (no interventions to prevent GBS disease). At vaccine efficacy of 70%, the programme is cost-effective at a maximum vaccine price per dose of 12 US$ (2016 US$), and very cost-effective at a maximum of $3/dose. The total costs of vaccination at $12 is $1,056,962 for one annual cohort of Gambian pregnant women. One-way sensitivity analysis showed that GBS incidence was the most influential parameter on the cost effectiveness ratio.

CONCLUSION

The introduction of a hexavalent vaccine would considerably reduce the current burden of GBS disease in The Gambia but to be cost-effective, the vaccine price per dose would need to be $12/dose or less.

Rectovaginal group B streptococcus colonization among pregnant women in Nicaragua: a systematic review and meta-analysis

BACKGROUND

Maternal colonization with group B Streptococcus (GBS) is a predictor of neonatal sepsis. In Nicaragua, neonatal sepsis is a major cause of hospitalization, but it can be prevented with intrapartum antibiotic prophylaxis. We undertook this study to estimate the pooled prevalence of rectovaginal GBS colonization among pregnant women 35-40-week gestation in Nicaragua, and sensitivity of GBS isolates to various antibiotics.

METHODS

We systematically searched electronic databases of peer-reviewed and unpublished literature using prespecified search terms. We included English- and Spanish-language studies of rectovaginal GBS colonization and/or antibiotic sensitivity of GBS isolates that followed internationally-recognized diagnostic standards, from various sites and years. Two reviewers independently abstracted data and assessed risk of study bias. We then meta-analyzed the pooled prevalence of rectovaginal GBS colonization and antibiotic sensitivity of GBS isolates. We performed subgroup analyses by geographic location, urbanicity, and study risk of bias.

MAIN RESULTS

Prevalence of rectovaginal GBS colonization from 13 samples in 11 studies was 0.14 (95% CI: 0.09, 0.21). Effect size heterogeneity was identified between coastal (0.12 [95% CI: 0.07, 0.19]) and central study sites (0.23 [95% CI: 0.18, 0.28]), and between predominantly rural (0.06 [95% CI: 0.02, 0.10]) and urban (0.28 [95% CI: 0.19, 0.37]) samples of pregnant women. GBS sensitivity to penicillin, the first-line antibiotic for intrapartum prophylaxis, was 0.89 (95% CI: 0.71, 1.00) based on seven studies.

CONCLUSIONS

Maternal GBS colonization was substantial in some study sites. Most GBS isolates are sensitive to recommended antibiotics, and intrapartum antibiotic prophylaxis may effectively prevent neonatal sepsis in Nicaragua.

Maternal Immunization and Antenatal Care Situation Analysis (MIACSA) study protocol: a multiregional, cross-sectional analysis of maternal immunization delivery strategies to reduce maternal and neonatal morbidity and mortality

INTRODUCTION

Maternal immunization (MI) with tetanus toxoid containing vaccine, is a safe and cost-effective way of preventing neonatal tetanus. Given the prospect of introducing new maternal vaccines in the near future, it is essential to identify and understand current policies, practices and unmet needs for introducing and/or scaling up MI in low-income and middle-income countries (LMICs).

METHODS AND ANALYSIS

The Maternal Immunization and Antenatal Care Situation Analysis (MIACSA) is a mixed methods, cross-sectional study that will collect data in four phases: (1) a review of global databases for selected health indicators in 136 LMICs; (2) a structured online survey directed at Maternal, Newborn and Child Health and Expanded Programme on Immunization focal points in all 136 LMICs; (3) semistructured telephone interviews of 30 selected LMICs and (4) 10 week-long country visits, including key informant interviews, health facility visits and focus group discussions. The principal analyses will assess correlations between the various aspects of MI delivery strategies and proxy measures of health systems performance related to vaccine-preventable disease control. The primary outcome will be a typology of existing MI delivery models, and secondary outcomes will include country profiles of child and maternal health indicators, and a MI gaps and needs analysis.

ETHICS AND DISSEMINATION

The protocol was approved by the WHO Ethics Review Committee (ERC.0002908). The results will be made available in a project report and submitted for publication in peer-reviewed journals that will be shared broadly among global health decision-makers, researchers, product developers and country-level stakeholders.

Group B Streptococcus: Trials and Tribulations

Group B Streptococcus (GBS) is estimated to have caused 319,000 cases of neonatal disease resulting in 90,000 infant deaths globally in 2015. It is also associated with maternal sepsis, preterm births, stillbirths and neonatal encephalopathy. There is a significant burden of neurologic impairment among survivors of infant GBS disease. Intrapartum antibiotic prophylaxis strategies have reduced the incidence of newborn early-onset GBS (occurring days 0-6) in some settings, but they are not feasible in many low and middle-income countries. A maternal vaccine given to pregnant women to stimulate passive transplacental transfer of protective antibodies has the potential to reduce maternal disease, adverse pregnancy outcomes and newborn disease. Phase I and II vaccine studies are occurring, but conducting phase III efficacy studies of a GBS vaccine candidate would require very large numbers due to the relatively low incidence of invasive GBS disease. It has therefore been proposed that alternative pathways to vaccine licensure should be explored, for example, through use of a regulatory approved correlate of protection and safety evaluation in mothers, fetuses and infants. These studies would then be followed-up with post-licensure phase IV studies in which vaccine effectiveness is evaluated.

Cost of antiretroviral treatment for HIV patients in two centres of North India

There is paucity of evidence on cost of antiretroviral therapy (ART) delivered through the public sector in India. Moreover, the Government of India is considering changing the criteria for introduction of ART to HIV patients, which is likely to have significant economic implications. In this paper, we assess the health system cost of ART services at two levels of health care delivery. Bottom-up costing was used to collect data on capital and recurrent resources consumed over a period of one year (April 2014–March 2015). Capital costs were annualized and shared costs apportioned to calculate annual and unit costs of providing ART care. Sensitivity analysis was undertaken to measure the extent of uncertainty in input prices. The annual per capita cost of ART therapy was INR 48,975 (USD738) in the Centre of Excellence (COE) and INR 24,954 (USD376) in the ART centre. Drugs contributed around 70% and 65% of total annual cost, followed by human resource (19% each) and capital cost (7%; 12%) in COE and ART centres, respectively. These provide a comprehensive assessment of the cost of ART care in India. The study estimates could be used for planning of services, as well as undertaking further cost-effectiveness studies.

Maternal immunisation: What have been the gains? Where are the gaps? What does the future hold?

The vaccination of pregnant women has enormous potential to protect not only mothers from vaccine-preventable diseases but also their infants through the passive acquisition of protective antibodies before they are able to themselves acquire protection through active childhood immunisations. Maternal tetanus programmes have been in place since 1989, and as of March 2018, only 14 countries in the world were still to reach maternal neonatal tetanus elimination status. This has saved hundreds of thousands of lives. Building on this success, influenza- and pertussis-containing vaccines have been recommended for pregnant women and introduced into immunisation programmes, albeit predominantly in resource-rich settings. These have highlighted some important challenges when additional immunisations are introduced into the antenatal context. With new vaccine candidates, such as respiratory syncytial virus (RSV) and group B streptococcus (GBS), on the horizon, it is important that we learn from these experiences, identify the information gaps, and close these to ensure safe and successful implementation of maternal vaccines in the future, particularly in low- and middle-income countries with a high burden of disease.

Aetiology of neonatal sepsis in Nigeria, and relevance of Group b streptococcus: A systematic review

BACKGROUND

Group B Streptococcus (GBS) causes invasive infections in neonates and has been implicated as a cause of prelabour rupture of membranes, preterm delivery and stillbirths. The success of phase II trials of polyvalent polysaccharide GBS vaccines indicates that these infections are potentially preventable. Nigeria is the most populous country in Africa with one of the highest birth rates, one of the highest neonatal sepsis incidence rates and one of the highest mortality rates in the world. Therefore, before the possible introduction of preventive strategies such as intrapartum antibiotic prophylaxis or GBS vaccine into Nigeria, it is vital that there is accurate data on the aetiology of neonatal sepsis and on the incidence of GBS neonatal sepsis in particular. The objective of this study was to determine the incidence and aetiology of neonatal sepsis in Nigeria with a focus on GBS sepsis and also to assess the potential impact of a GBS vaccine.

METHODS

A literature search was conducted on the databases of African journals online, PubMed and Google Scholar for works conducted between 1987 to 2017. Case reports, reviews, and studies not stating specific culture methods or specific bacteria isolated were excluded. Data extracted included; incidence of neonatal sepsis, method of blood culture, blood volume, sample size, bacterial agents isolated and history of antibiotic use. PRISMA guidelines were followed and modified Down's and Black criteria used to evaluate the quality of studies.

RESULTS

A total of 5,114 studies were reviewed for neonatal sepsis out of which 24 consisting of a total of 2,280 cases were selected for final review. Nine studies met criteria for assessment of hospital based incidence of neonatal sepsis representing 31,305 hospital births. The incidence of neonatal sepsis was 18.2/1000 livebirths with range from 7-55/1000 livebirths while the GBS incidence was 0.06/1000 livebirths with range from 0-2/1000 live births. We discovered various limitations such as identification techniques that could result in underestimation of the true incidence of GBS sepsis. Pathogens such as Klebsiella pneumoniae and Staphylococcus aureus were more commonly isolated than GBS.

IMPLICATIONS OF KEY FINDINGS

The hospital based incidence of neonatal sepsis was high at 18.2/1000 live births while that due to GBS was 0.06/1000 live births. The burden of neonatal sepsis, including that attributable to GBS is substantial and could be reduced by preventive strategies such as intrapartum antibiotic prophylaxis or GBS vaccine. There is however very sparse meaningful data currently. Well planned prospective studies with larger sample sizes, more advanced isolation and identification techniques and those following up invasive disease cases for possible short and long term sequelae are needed-not only prior to possible introduction of the vaccine to determine the baseline epidemiology, but also thereafter to monitor its impact on the population. Strategies need to be developed to also reduce the morbidity and mortality attributable to other bacteria that have an incidence even greater than that of GBS.

Cost effectiveness of mHealth intervention by community health workers for reducing maternal and newborn mortality in rural Uttar Pradesh, India

BACKGROUND

A variety of mobile-based health technologies (mHealth) have been developed for use by community health workers to augment their performance. One such mHealth intervention-ReMiND program, was implemented in a poor performing district of India. Despite some research on the extent of its effectiveness, there is significant dearth of evidence on cost-effectiveness of such mHealth interventions. In this paper we evaluated the incremental cost per disability adjusted life year (DALY) averted as a result of ReMiND intervention as compared to routine maternal and child health programs without ReMiND.

METHODS

A decision tree was parameterized on MS-Excel spreadsheet to estimate the change in DALYs and cost as a result of implementing ReMiND intervention compared with routine care, from both health system and societal perspective. A time horizon of 10 years starting from base year of 2011 was considered appropriate to cover all costs and effects comprehensively. All costs, including those during start-up and implementation phase, besides other costs on the health system or households were estimated. Consequences were measured as part of an impact assessment study which used a quasi-experimental design. Proximal outputs in terms of changes in service coverage were modelled to estimate maternal and infant illnesses and deaths averted, and DALYs averted in Uttar Pradesh state of India. Probabilistic sensitivity analysis was undertaken to account for parameter uncertainties.

RESULTS

Cumulatively, from year 2011 to 2020, implementation of ReMiND intervention in UP would result in a reduction of 312 maternal and 149,468 neonatal deaths. This implies that ReMiND program led to a reduction of 0.2% maternal and 5.3% neonatal deaths. Overall, ReMiND is a cost saving intervention from societal perspective. From health system perspective, ReMiND incurs an incremental cost of INR 12,993 (USD 205) per DALY averted and INR 371,577 (USD 5865) per death averted.

CONCLUSIONS

Overall, findings of our study suggest strongly that the mHealth intervention as part of ReMiND program is cost saving from a societal perspective and should be considered for replication elsewhere in other states.

A multi-country study of dengue vaccination strategies with Dengvaxia and a future vaccine candidate in three dengue-endemic countries: Vietnam, Thailand, and Colombia

BACKGROUND

The dengue vaccination era began when Dengvaxia (CYD-TDV) became available in 2016. In addition, several second-generation vaccine candidates are currently in phase 3 trials, suggesting that a broader availability of dengue vaccines may be possible in the near future. Advancing on the recent WHO-SAGE recommendations for the safe and effective use of CYD-TDV at the regional level on average, this study investigates the vaccination impacts and cost-effectiveness of CYD-TDV and of a hypothetical new vaccine candidate (NVC) in a country-specific manner for three endemic countries: Vietnam, Thailand, and Colombia.

METHODS

The vaccination impacts of CYD-TDV and NVC were derived by fitting the empirical seroprevalence rates of 9 year olds into an individual-based meta-population transmission model, previously used for the WHO-SAGE working group. The disability-adjusted life years were estimated by applying country-specific parametric values. The cost-effectiveness analyses of four intervention strategies in combination with routine and catch-up campaigns were compared for both vaccines to inform decision makers regarding the most suitable immunization program in each of the three countries.

RESULTS AND CONCLUSION

Both CYD-TDV and NVC could be cost-effective at the DALY threshold cost of $2000 depending upon vaccination costs. With CYD-TDV, targeting 9 year olds in routine vaccination programs and 10-29 year olds as a one-off catch-up campaign was the most cost-effective strategy in all three countries. With NVC, while the most cost-effective strategy was to vaccinate 9-29 and 9-18 year olds in Vietnam and Thailand respectively, vaccinating younger age cohorts between 1 and 5 years old in Colombia was more cost-effective than other strategies. Given that three countries will soon face decisions regarding whether and how to incorporate CYD-TDV or future dengue vaccines into their budget-constrained national immunization programs, the current study outcomes can be used to help decision makers understand the expected impacts and cost-effectiveness of such vaccines.