Uncovering the Drivers of Childhood Immunization Inequality with Caregivers, Community Members and Health System Stakeholders: Results from a Human-Centered Design Study in DRC, Mozambique and Nigeria

BACKGROUND

The importance of immunization for child survival underscores the need to eliminate immunization inequalities. Few existing studies of inequalities use approaches that view the challenges and potential solutions from the perspective of caregivers. This study aimed to identify barriers and context-appropriate solutions by engaging deeply with caregivers, community members, health workers, and other health system actors through participatory action research, intersectionality, and human-centered design lenses.

METHODS

This study was conducted in the Demographic Republic of Congo, Mozambique and Nigeria. Rapid qualitative research was followed by co-creation workshops with study participants to identify solutions. We analyzed the data using the UNICEF Journey to Health and Immunization Framework.

RESULTS

Caregivers of zero-dose and under-immunized children faced multiple intersecting and interacting barriers related to gender, poverty, geographic access, and service experience. Immunization programs were not aligned with needs of the most vulnerable due to the sub-optimal implementation of pro-equity strategies, such as outreach vaccination. Caregivers and communities identified feasible solutions through co-creation workshops and this approach should be used whenever possible to inform local planning.

CONCLUSIONS

Policymakers and managers can integrate HCD and intersectionality mindsets into existing planning and assessment processes, and focus on overcoming root causes of sub-optimal implementation.

Emergence of a multidrug-resistant and virulent Streptococcus pneumoniae lineage mediates serotype replacement after PCV13: an international whole-genome sequencing study

BACKGROUND

Serotype 24F is one of the emerging pneumococcal serotypes after the introduction of pneumococcal conjugate vaccine (PCV). We aimed to identify lineages driving the increase of serotype 24F in France and place these findings into a global context.

METHODS

Whole-genome sequencing was performed on a collection of serotype 24F pneumococci from asymptomatic colonisation (n=229) and invasive disease (n=190) isolates among individuals younger than 18 years in France, from 2003 to 2018. To provide a global context, we included an additional collection of 24F isolates in the Global Pneumococcal Sequencing (GPS) project database for analysis. A Global Pneumococcal Sequence Cluster (GPSC) and a clonal complex (CC) were assigned to each genome. Phylogenetic, evolutionary, and spatiotemporal analysis were conducted using the same 24F collection and supplemented with a global collection of genomes belonging to the lineage of interest from the GPS project database (n=25 590).

FINDINGS

Serotype 24F was identified in numerous countries mainly due to the clonal spread of three lineages: GPSC10 (CC230), GPSC16 (CC156), and GPSC206 (CC7701). GPSC10 was the only multidrug-resistant lineage. GPSC10 drove the increase in 24F in France and had high invasive disease potential. The international dataset of GPSC10 (n=888) revealed that this lineage expressed 16 other serotypes, with only six included in 13-valent PCV (PCV13). All serotype 24F isolates were clustered in a single clade within the GPSC10 phylogeny and long-range transmissions were detected from Europe to other continents. Spatiotemporal analysis showed GPSC10-24F took 3-5 years to spread across France and a rapid change of serotype composition from PCV13 serotype 19A to 24F during the introduction of PCV13 was observed in neighbouring country Spain.

INTERPRETATION

Our work reveals that GPSC10 alone is a challenge for serotype-based vaccine strategy. More systematic investigation to identify lineages like GPSC10 will better inform and improve next-generation preventive strategies against pneumococcal diseases.

FUNDING

Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control and Prevention.

A Streptococcus pneumoniae lineage usually associated with pneumococcal conjugate vaccine (PCV) serotypes is the most common cause of serotype 35B invasive disease in South Africa, following routine use of PCV

Pneumococcal serotype 35B is an important non-conjugate vaccine (non-PCV) serotype. Its continued emergence, post-PCV7 in the USA, was associated with expansion of a pre-existing 35B clone (clonal complex [CC] 558) along with post-PCV13 emergence of a non-35B clone previously associated with PCV serotypes (CC156). This study describes lineages circulating among 35B isolates in South Africa before and after PCV introduction. We also compared 35B isolates belonging to a predominant 35B lineage in South Africa (GPSC5), with isolates belonging to the same lineage in other parts of the world. Serotype 35B isolates that caused invasive pneumococcal disease in South Africa in 2005–2014 were characterized by whole-genome sequencing (WGS). Multi-locus sequence types and global pneumococcal sequence clusters (GPSCs) were derived from WGS data of 63 35B isolates obtained in 2005–2014. A total of 262 isolates that belong to GPSC5 (115 isolates from South Africa and 147 from other countries) that were sequenced as part of the global pneumococcal sequencing (GPS) project were included for comparison. Serotype 35B isolates from South Africa were differentiated into seven GPSCs and GPSC5 was most common (49 %, 31/63). While 35B was the most common serotype among GPSC5/CC172 isolates in South Africa during the PCV13 period (66 %, 29/44), 23F was the most common serotype during both the pre-PCV (80 %, 37/46) and PCV7 period (32 %, 8/25). Serotype 35B represented 15 % (40/262) of GPSC5 isolates within the global GPS database and 75 % (31/40) were from South Africa. The predominance of the GPSC5 lineage within non-vaccine serotype 35B, is possibly unique to South Africa and warrants further molecular surveillance of pneumococci.

Community-based antibiotic access and use in six low-income and middle-income countries: a mixed-method approach

BACKGROUND

Antimicrobial misuse is common in low-income and middle-income countries (LMICs), and this practice is a driver of antibiotic resistance. We compared community-based antibiotic access and use practices across communities in LMICs to identify contextually specific targets for interventions to improve antibiotic use practices.

METHODS

We did quantitative and qualitative assessments of antibiotic access and use in six LMICs across Africa (Mozambique, Ghana, and South Africa) and Asia (Bangladesh, Vietnam, and Thailand) over a 2·5-year study period (July 1, 2016-Dec 31, 2018). We did quantitative assessments of community antibiotic access and use through supplier mapping, customer exit interviews, and household surveys. These quantitative assessments were triangulated with qualitative drug supplier and consumer interviews and discussions.

FINDINGS

Vietnam and Bangladesh had the largest proportions of non-licensed antibiotic dispensing points. For mild illness, drug stores were the most common point of contact when seeking antibiotics in most countries, except South Africa and Mozambique, where public facilities were most common. Self-medication with antibiotics was found to be widespread in Vietnam (55·2% of antibiotics dispensed without prescription), Bangladesh (45·7%), and Ghana (36·1%), but less so in Mozambique (8·0%), South Africa (1·2%), and Thailand (3·9%). Self-medication was considered to be less time consuming, cheaper, and overall, more convenient than accessing them through health-care facilities. Factors determining where treatment was sought often involved relevant policies, trust in the supplier and the drug, disease severity, and whether the antibiotic was intended for a child. Confusion regarding how to identify oral antibiotics was revealed in both Africa and Asia.

INTERPRETATION

Contextual complexities and differences between countries with different incomes, policy frameworks, and cultural norms were revealed. These contextual differences render a single strategy inadequate and instead necessitate context-tailored, integrated intervention packages to improve antibiotic use in LMICs as part of global efforts to combat antibiotic resistance.

FUNDING

Wellcome Trust and Volkswagen Foundation.

Visualizing variation within Global Pneumococcal Sequence Clusters (GPSCs) and country population snapshots to contextualize pneumococcal isolates

Knowledge of pneumococcal lineages, their geographic distribution and antibiotic resistance patterns, can give insights into global pneumococcal disease. We provide interactive bioinformatic outputs to explore such topics, aiming to increase dissemination of genomic insights to the wider community, without the need for specialist training. We prepared 12 country-specific phylogenetic snapshots, and international phylogenetic snapshots of 73 common Global Pneumococcal Sequence Clusters (GPSCs) previously defined using PopPUNK, and present them in Microreact. Gene presence and absence defined using Roary, and recombination profiles derived from Gubbins are presented in Phandango for each GPSC. Temporal phylogenetic signal was assessed for each GPSC using BactDating. We provide examples of how such resources can be used. In our example use of a country-specific phylogenetic snapshot we determined that serotype 14 was observed in nine unrelated genetic backgrounds in South Africa. The international phylogenetic snapshot of GPSC9, in which most serotype 14 isolates from South Africa were observed, highlights that there were three independent sub-clusters represented by South African serotype 14 isolates. We estimated from the GPSC9-dated tree that the sub-clusters were each established in South Africa during the 1980s. We show how recombination plots allowed the identification of a 20 kb recombination spanning the capsular polysaccharide locus within GPSC97. This was consistent with a switch from serotype 6A to 19A estimated to have occured in the 1990s from the GPSC97-dated tree. Plots of gene presence/absence of resistance genes (tet, erm, cat) across the GPSC23 phylogeny were consistent with acquisition of a composite transposon. We estimated from the GPSC23-dated tree that the acquisition occurred between 1953 and 1975. Finally, we demonstrate the assignment of GPSC31 to 17 externally generated pneumococcal serotype 1 assemblies from Utah via Pathogenwatch. Most of the Utah isolates clustered within GPSC31 in a USA-specific clade with the most recent common ancestor estimated between 1958 and 1981. The resources we have provided can be used to explore to data, test hypothesis and generate new hypotheses. The accessible assignment of GPSCs allows others to contextualize their own collections beyond the data presented here.

Rethinking integrated nutrition-health strategies to address micronutrient deficiencies in children under five in Mozambique

In Mozambique, about two thirds of children 6–59 months of age are affected by vitamin A deficiency and anaemia. The objective of this case study is to provide programme considerations for planning, implementing, monitoring, and evaluating vitamin A and iron deficiency interventions within the context of lessons learned to date for vitamin A supplementation, micronutrient powders (MNPs), and food‐based strategies. For 15 years, the Mozambique Ministry of Health implemented twice‐yearly vitamin A supplementation through both campaigns and routine health services. Yet coverage in 2017 (55%) was not much higher than in 2003 (44%). Reaching every district/reaching every child, a strategy adapted from the field of immunization, was used to achieve equitable coverage of vitamin A and for microplanning of outreach services in health facilities, with support from the Maternal and Child Survival Program. In Mozambique, a free or subsidized distribution model for MNPs has been rolled out, yet integration of MNPs into infant and young child feeding programming (i.e., cooking demonstrations) is needed to reinforce “the who, what, and why” of MNPs through culturally sensitive behaviour change communication. Food‐based strategies to promote dietary diversity, such as through complementary feeding recipes, are also critical. To harmonize efforts, the Mozambique government should consider the development of a national strategy for the prevention and control of micronutrient malnutrition, with clear monitoring and evaluation targets. Ongoing monitoring of the prevalence of micronutrient deficiencies and coverage of implemented micronutrient interventions is needed to make evidence‐based decisions to drive nutrition–health programming.

Pneumococcal carriage and serotype distribution among children with and without pneumonia in Mozambique, 2014-2016

Background

Pneumococcal colonization is a precursor to pneumonia, and pneumococcal conjugate vaccines (PCV) can decrease vaccine-type (VT) colonization. Pneumococcal colonization studies are traditionally done among healthy children in the community; however, VT colonization prevalence may differ between these children and those with pneumonia. We assessed overall and VT pneumococcal colonization and factors associated with colonization among children with and without pneumonia after Mozambique introduced 10-valent PCV (PCV10) in 2013.

Methods

We used data from ongoing pneumonia surveillance in children aged <5 years and from cross-sectional nasopharyngeal colonization surveys conducted in October 2014 –April 2015 and October 2015 –May 2016. Pneumonia was defined using WHO standard criteria for radiologically confirmed pneumonia. Children with pneumonia enrolled from January 2014 –April 2016 were compared to children without pneumonia enrolled from the cross-sectional surveys. Clinical data and nasopharyngeal (NP) swabs were collected from each child. NP specimens were cultured for pneumococci, and culture-negative specimens from children with pneumonia underwent polymerase chain reaction (PCR).

Results

Of 778 and 927 children with and without pneumonia, 97.4% and 27.0% were exposed to antibiotics before swab collection, respectively. Based on culture, pneumococcal colonization was 45.1% for children with and 84.5% for children without pneumonia (P<0.001); VT pneumococcal colonization was 18.6% for children with and 23.4% for children without pneumonia (P = 0.02). The addition of PCR in children with pneumonia increased overall and VT-pneumococcal colonization to 79.2% and 31.1%, respectively. In multivariable analysis including PCR results, pneumonia was associated with VT pneumococcal colonization (adjusted OR: 1.4, 95%CI: 1.10–1.78).

Conclusion

Vaccine-type pneumococcal colonization remains common among children with and without pneumonia post-PCV10 introduction in Mozambique. In a population of children with high antibiotic exposure, the use of PCR for culture-negative NP swabs can improve assessment of pneumococcal colonization and circulating serotypes.

BCG vaccination in southern rural Mozambique: an overview of coverage and its determinants based on data from the demographic and health surveillance system in the district of Manhiça

Background

Over the past four decades, the World Health Organization established the Expanded Programme on Immunization (EPI) to foster universal access to all relevant vaccines for all children at risk. The success of this program has been undeniable, but requires periodic monitoring to ensure that coverage rates remain high. The aim of this study was to measure the BCG vaccination coverage in Manhiça district, a high TB burden rural area of Southern Mozambique and to investigate factors that may be associated with BCG vaccination.

Methods

We used data from the Health and Demographic Surveillance System (HDSS) run by the Manhiça Health Research Centre (CISM) in the district of Manhiça. A questionnaire was added in the annual HDSS round visits to retrospectively collect the vaccination history of children under the age of 3 years. Vaccinations are registered in the National Health Cards which are universally distributed at birth. This information was collected for children born from 2011 to 2014. Data on whether a child was vaccinated for BCG were collected from these National Health Cards and/or BCG scar assessment.

Results

A total of 10,875 number of children were eligible for the study and 7903 presented the health card. BCG coverage was 97.4% for children holding a health card. A BCG-compatible scar was observed in 99.0% of all children and in 99.6% of children with recorded BCG in the card. A total of 93.4% of children had been vaccinated with BCG within their first 28 days of life. None of the factors analysed were found to be associated with lack of BCG vaccination except for living in the municipality of Maluana compared to living in the municipality of Manhiça; (OR = 1.89, 95% CI: 1.18-3.00). Coverage for other EPI vaccines during the first year of life was similarly high, but decreased for subsequent doses.

Conclusions

BCG coverage is high and timely administered. Almost all vaccinated infants develop scar, which is a useful proxy for monitoring BCG vaccine implementation.

Electronic supplementary material

The online version of this article (10.1186/s12887-018-1003-4) contains supplementary material, which is available to authorized users.

Community-level antibiotic access and use (ABACUS) in low- and middle-income countries: Finding targets for social interventions to improve appropriate antimicrobial use - an observational multi-centre study

In many low- and middle-income countries (LMICs), a poor link between antibiotic policies and practices exists. Numerous contextual factors may influence the degree of antibiotic access, appropriateness of antibiotic provision, and actual use in communities. Therefore, improving appropriateness of antibiotic use in different communities in LMICs probably requires interventions tailored to the setting of interest, accounting for cultural context. Here we present the ABACUS study (AntiBiotic ACcess and USe), which employs a unique approach and infrastructure, enabling quantitative validation, contextualization of determinants, and cross-continent comparisons of antibiotic access and use. The community infrastructure for this study is the INDEPTH-Network (International Network for the Demographic Evaluation of Populations and Their Health in Developing Countries), which facilitates health and population research through an established health and demographic surveillance system. After an initial round of formative qualitative research with community members and antibiotic suppliers in three African and three Asian countries, household surveys will assess the appropriateness of antibiotic access, provision and use. Results from this sample will be validated against a systematically conducted inventory of suppliers. All potential antibiotic suppliers will be mapped and characterized. Subsequently, their supply of antibiotics to the community will be measured through customer exit interviews, which tend to be more reliable than bulk purchase or sales data. Discrepancies identified between reported and observed antibiotic practices will be investigated in further qualitative interviews. Amartya Sen’s Capability Approach will be employed to identify the conversion factors that determine whether or not, and the extent to which appropriate provision of antibiotics may lead to appropriate access and use of antibiotics. Currently, the study is ongoing and expected to conclude by 2019. ABACUS will provide important new insights into antibiotic practices in LMICs to inform social interventions aimed at promoting optimal antibiotic use, thereby preserving antibiotic effectiveness.

Infant mortality and morbidity associated with preterm and small-for-gestational-age births in Southern Mozambique: A retrospective cohort study

Background

Preterm and small for gestational age (SGA) births have been associated with adverse outcomes during the first stages of life. We evaluated the morbidity and mortality associated with preterm and SGA births during the first year of life in a rural area of Southern Mozambique.

Methods

This is a retrospective cohort study using previously collected data from children born at the Manhiça District Hospital in two different periods (2003–2005 and 2010–2012). Newborns were classified as being preterm and/or SGA or as babies not fulfilling any of the previous conditions (term non-SGA). All children were followed up for a year for morbidity and mortality outcomes.

Results

A total of 5574 live babies were included in the analysis. The prevalence of preterm delivery was 6.2% (345/5574); the prevalence of SGA was 14.0% (776/5542) and 2.2% (114/5542) of the children presented both conditions. During the neonatal period, preterm delivery and SGA were associated with 13 (HR: 13.0, 95% CI 4.0–42.2) and 5 times (HR: 4.5, 95% CI: 1.6–12.6) higher mortality compared to term non SGA babies. Risk of hospitalization was only increased when both conditions were present (IRR: 3.5, 95%CI: 1.5–8.1). Mortality is also increased during the entire first year, although at a lower rate.

Conclusions

Neonatal and infant mortality rates are remarkably high among preterm and SGA babies in southern Mozambique. These increased rates are concentrated within the neonatal period. Prompt identification of these conditions is needed to implement interventions aimed at increasing survival of these high-risk newborns.

Understanding pneumococcal serotype 1 biology through population genomic analysis

BACKGROUND

Pneumococcus kills over one million children annually and over 90 % of these deaths occur in low-income countries especially in Sub-Saharan Africa (SSA) where HIV exacerbates the disease burden. In SSA, serotype 1 pneumococci particularly the endemic ST217 clone, causes majority of the pneumococcal disease burden. To understand the evolution of the virulent ST217 clone, we analysed ST217 whole genomes from isolates sampled from African and Asian countries.

METHODS

We analysed 226 whole genome sequences from the ST217 lineage sampled from 9 African and 4 Asian countries. We constructed a whole genome alignment and used it for phylogenetic and coalescent analyses. We also screened the genomes to determine presence of antibiotic resistance conferring genes.

RESULTS

Population structure analysis grouped the ST217 isolates into five sequence clusters (SCs), which were highly associated with different geographical regions and showed limited intracontinental and intercontinental spread. The SCs showed lower than expected genomic sequence, which suggested strong purifying selection and small population sizes caused by bottlenecks. Recombination rates varied between the SCs but were lower than in other successful clones such as PMEN1. African isolates showed higher prevalence of antibiotic resistance genes than Asian isolates. Interestingly, certain West African isolates harbored a defective chloramphenicol and tetracycline resistance-conferring element (Tn5253) with a deletion in the loci encoding the chloramphenicol resistance gene (cat pC194), which caused lower chloramphenicol than tetracycline resistance. Furthermore, certain genes that promote colonisation were absent in the isolates, which may contribute to serotype 1's rarity in carriage and consequently its lower recombination rates.

CONCLUSIONS

The high phylogeographic diversity of the ST217 clone shows that this clone has been in circulation globally for a long time, which allowed its diversification and adaptation in different geographical regions. Such geographic adaptation reflects local variations in selection pressures in different locales. Further studies will be required to fully understand the biological mechanisms which makes the ST217 clone highly invasive but unable to successfully colonise the human nasopharynx for long durations which results in lower recombination rates.

The global threat of antimicrobial resistance: science for intervention

In the last decade we have witnessed a dramatic increase in the proportion and absolute number of bacterial pathogens resistant to multiple antibacterial agents. Multidrug-resistant bacteria are currently considered as an emergent global disease and a major public health problem. The B-Debate meeting brought together renowned experts representing the main stakeholders (i.e. policy makers, public health authorities, regulatory agencies, pharmaceutical companies and the scientific community at large) to review the global threat of antibiotic resistance and come up with a coordinated set of strategies to fight antimicrobial resistance in a multifaceted approach. We summarize the views of the B-Debate participants regarding the current situation of antimicrobial resistance in animals and the food chain, within the community and the healthcare setting as well as the role of the environment and the development of novel diagnostic and therapeutic strategies, providing expert recommendations to tackle the global threat of antimicrobial resistance.

A phase 3 trial of RTS,S/AS01 malaria vaccine in African infants

BACKGROUND

The candidate malaria vaccine RTS,S/AS01 reduced episodes of both clinical and severe malaria in children 5 to 17 months of age by approximately 50% in an ongoing phase 3 trial. We studied infants 6 to 12 weeks of age recruited for the same trial.

METHODS

We administered RTS,S/AS01 or a comparator vaccine to 6537 infants who were 6 to 12 weeks of age at the time of the first vaccination in conjunction with Expanded Program on Immunization (EPI) vaccines in a three-dose monthly schedule. Vaccine efficacy against the first or only episode of clinical malaria during the 12 months after vaccination, a coprimary end point, was analyzed with the use of Cox regression. Vaccine efficacy against all malaria episodes, vaccine efficacy against severe malaria, safety, and immunogenicity were also assessed.

RESULTS

The incidence of the first or only episode of clinical malaria in the intention-to-treat population during the 14 months after the first dose of vaccine was 0.31 per person-year in the RTS,S/AS01 group and 0.40 per person-year in the control group, for a vaccine efficacy of 30.1% (95% confidence interval [CI], 23.6 to 36.1). Vaccine efficacy in the per-protocol population was 31.3% (97.5% CI, 23.6 to 38.3). Vaccine efficacy against severe malaria was 26.0% (95% CI, -7.4 to 48.6) in the intention-to-treat population and 36.6% (95% CI, 4.6 to 57.7) in the per-protocol population. Serious adverse events occurred with a similar frequency in the two study groups. One month after administration of the third dose of RTS,S/AS01, 99.7% of children were positive for anti-circumsporozoite antibodies, with a geometric mean titer of 209 EU per milliliter (95% CI, 197 to 222).

CONCLUSIONS

The RTS,S/AS01 vaccine coadministered with EPI vaccines provided modest protection against both clinical and severe malaria in young infants. (Funded by GlaxoSmithKline Biologicals and the PATH Malaria Vaccine Initiative; RTS,S ClinicalTrials.gov number, NCT00866619.).

Reduction of antimalarial antibodies by HIV infection is associated with increased risk of Plasmodium falciparum cord blood infection

BACKGROUND

Plasmodium falciparum infection in pregnancy can lead to congenital malaria, which has detrimental health consequences for infants. Human immunodeficiency virus (HIV) might increase cord blood P. falciparum infection by decreasing maternal antimalarial-specific antibodies.

METHODS

HIV-negative (n=133) and HIV-positive (n=55) Mozambican pregnant women were assessed at delivery for maternal and cord P. falciparum infection by quantitative polymerase chain reaction (qPCR) and P. falciparum-specific antibodies by enzyme-linked immunosorbent assay and flow cytometry.

RESULTS

Prevalence of qPCR-detected cord blood infection was 8.0%. Risk of cord infection was increased in presence of HIV (adjusted odds ratio [AOR], 3.80; P=.04) and placental malaria (AOR, 22.08; P=.002) after adjusting for clinical variables. The odds of having a high immunoglobulin G response to chondrotin sulphate A-binding infected erythrocytes, parasite lysate, and erythrocyte-binding antigen-175 were reduced among HIV-positive women (P < .001, .048, and .056, respectively) and among women with cord P. falciparum infection (P = .009, .04, and .046, respectively). In multivariate analysis including maternal HIV status, placental malaria, and antibody responses, HIV was no longer associated with cord blood infection (P = .11).

CONCLUSIONS

HIV-associated impairment of antibody responses in pregnant women may contribute to a higher transmission of P. falciparum to their infants.

Costs associated with low birth weight in a rural area of Southern Mozambique

BACKGROUND

Low Birth Weight (LBW) is prevalent in low-income countries. Even though the economic evaluation of interventions to reduce this burden is essential to guide health policies, data on costs associated with LBW are scarce. This study aims to estimate the costs to the health system and to the household and the Disability Adjusted Life Years (DALYs) arising from infant deaths associated with LBW in Southern Mozambique.

METHODS AND FINDINGS

Costs incurred by the households were collected through exit surveys. Health system costs were gathered from data obtained onsite and from published information. DALYs due to death of LBW babies were based on local estimates of prevalence of LBW (12%), very low birth weight (VLBW) (1%) and of case fatality rates compared to non-LBW weight babies [for LBW (12%) and VLBW (80%)]. Costs associated with LBW excess morbidity were calculated on the incremental number of hospital admissions in LBW babies compared to non-LBW weight babies. Direct and indirect household costs for routine health care were 24.12 US$ (CI 95% 21.51; 26.26). An increase in birth weight of 100 grams would lead to a 53% decrease in these costs. Direct and indirect household costs for hospital admissions were 8.50 US$ (CI 95% 6.33; 10.72). Of the 3,322 live births that occurred in one year in the study area, health system costs associated to LBW (routine health care and excess morbidity) and DALYs were 169,957.61 US$ (CI 95% 144,900.00; 195,500.00) and 2,746.06, respectively.

CONCLUSIONS

This first cost evaluation of LBW in a low-income country shows that reducing the prevalence of LBW would translate into important cost savings to the health system and the household. These results are of relevance for similar settings and should serve to promote interventions aimed at improving maternal care.

Assessment of the epidemiology and burden of measles in Southern Mozambique

Measles has been a major killer among vaccine-preventable diseases in children < 5 years of age in developing countries. Despite progress in global efforts to reduce mortality, measles remains a public health problem. Hospital-based measles surveillance was conducted in Manhica, Mozambique (July 2001-September 2004). Suspected cases and community-based controls were enrolled, and blood was collected for immunoglobulin M (IgM) confirmation. Two hundred fifty-three suspected cases and 477 controls were enrolled, with 85% (216 of 253) cases reported during a measles outbreak. Measles-IgM confirmation was 30% among suspected cases and 5% in controls. Fifty-eight percent (14 of 24) of laboratory-confirmed cases had records indicating previous measles vaccination. Mortality was 3% (8 of 246) among cases and 1% among controls (6 of 426). Forty-five percent (33 of 74) of cases were < 24 months of age and 22% occurred in infants < 9 months of age and were associated with a high case-fatality rate (25%). Our data suggest that improved diagnostics, new tools to protect infants < 9 months of age, and a supplemental dose of measles vaccine could assist measles control.

Impact of malaria at the end of pregnancy on infant mortality and morbidity

BACKGROUND

There is some consensus that malaria in pregnancy may negatively affect infant's mortality and malaria morbidity, but there is less evidence concerning the factors involved.

METHODS

A total of 1030 Mozambican pregnant women were enrolled in a randomized, placebo-controlled trial of intermittent preventive treatment with sulfadoxine-pyrimethamine, and their infants were followed up throughout infancy. Overall mortality and malaria morbidity rates were recorded. The association of maternal and fetal risk factors with infant mortality and malaria morbidity was assessed.

RESULTS

There were 58 infant deaths among 997 live-born infants. The risk of dying during infancy was increased among infants born to women with acute placental infection (odds ratio [OR], 5.08 [95% confidence interval (CI), 1.77-14.53)], parasitemia in cord blood (OR, 19.31 [95% CI, 4.44-84.02]), low birth weight (OR, 2.82 [95% CI, 1.27-6.28]) or prematurity (OR, 3.19 [95% CI, 1.14-8.95]). Infants born to women who had clinical malaria during pregnancy (OR, 1.96 [95% CI, 1.13-3.41]) or acute placental infection (OR, 4.63 [95% CI, 2.10-10.24]) had an increased risk of clinical malaria during infancy.

CONCLUSIONS

Malaria infection at the end of pregnancy and maternal clinical malaria negatively impact survival and malaria morbidity in infancy. Effective clinical management and prevention of malaria in pregnancy may improve infant's health and survival.

Malaria prevention with IPTp during pregnancy reduces neonatal mortality

BACKGROUND

In the global context of a reduction of under-five mortality, neonatal mortality is an increasingly relevant component of this mortality. Malaria in pregnancy may affect neonatal survival, though no strong evidence exists to support this association.

METHODS

In the context of a randomised, placebo-controlled trial of intermittent preventive treatment (IPTp) with sulphadoxine-pyrimethamine (SP) in 1030 Mozambican pregnant women, 997 newborns were followed up until 12 months of age. There were 500 live borns to women who received placebo and 497 to those who received SP.

FINDINGS

There were 58 infant deaths; 60.4% occurred in children born to women who received placebo and 39.6% to women who received IPTp (p = 0.136). There were 25 neonatal deaths; 72% occurred in the placebo group and 28% in the IPTp group (p = 0.041). Of the 20 deaths that occurred in the first week of life, 75% were babies born to women in the placebo group and 25% to those in the IPTp group (p = 0.039). IPTp reduced neonatal mortality by 61.3% (95% CI 7.4%, 83.8%); p = 0.024].

CONCLUSIONS

Malaria prevention with SP in pregnancy can reduce neonatal mortality. Mechanisms associated with increased malaria infection at the end of pregnancy may explain the excess mortality in the malaria less protected group. Alternatively, SP may have reduced the risk of neonatal infections. These findings are of relevance to promote the implementation of IPTp with SP, and provide insights into the understanding of the pathophysiological mechanisms through which maternal malaria affects fetal and neonatal health.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00209781.

The effect of intermittent preventive treatment during pregnancy on malarial antibodies depends on HIV status and is not associated with poor delivery outcomes

BACKGROUND

Intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended for malaria prevention in sub-Saharan Africa. However, studies reporting the effect of IPTp on malaria-specific immunity are scarce and are based on findings in human immunodeficiency virus (HIV)-negative primigravidae.

METHODS

Plasma samples obtained from 302 pregnant women (177 who were HIV negative, 88 who were HIV positive, and 37 who were of unknown HIV status) participating in a placebo-controlled trial of IPTp with SP (IPTp-SP) were analyzed for the presence of antibodies against merozoite antigens, whole asexual parasites, and variant surface antigens from chondroitin sulfate A-binding and nonbinding lines. Antibody levels were compared between intervention groups, and their association with morbidity outcomes was assessed.

RESULTS

HIV-positive mothers receiving SP had lower levels of peripheral antibodies against apical membrane antigen-1 and variant surface antigens, as well as lower levels of cord antibodies against erythrocyte-binding antigen-175 and parasite lysate, than did HIV-positive placebo recipients. No difference between intervention groups was observed among HIV-negative mothers. High antibody levels were associated with maternal infection and an increased risk of a first malaria episode in infants. Antibody responses were not consistently associated with reduced maternal anemia, prematurity, or low birth weight.

CONCLUSIONS

The IPTp-associated reduction in antibodies in HIV-infected women, but not in HIV-uninfected women, may reflect a higher efficacy of the intervention in preventing malaria among HIV-positive mothers. This reduction did not translate into an enhanced risk of malaria-associated morbidity in mothers and infants. Trial registration. Clinicaltrials.gov identifier NCT00209781.

A variant in the gene FUT9 is associated with susceptibility to placental malaria infection

Malaria in pregnancy forms a substantial part of the worldwide burden of malaria, with an estimated annual death toll of up to 200 000 infants, as well as increased maternal morbidity and mortality. Studies of genetic susceptibility to malaria have so far focused on infant malaria, with only a few studies investigating the genetic basis of placental malaria, focusing only on a limited number of candidate genes. The aim of this study therefore was to identify novel host genetic factors involved in placental malaria infection. To this end we carried out a nested case-control study on 180 Mozambican pregnant women with placental malaria infection, and 180 controls within an intervention trial of malaria prevention. We genotyped 880 SNPs in a set of 64 functionally related genes involved in glycosylation and innate immunity. A single nucleotide polymorphism (SNP) located in the gene FUT9, rs3811070, was significantly associated with placental malaria infection (odds ratio = 2.31, permutation P-value=0.028). Haplotypic analysis revealed a similarly strong association of a common haplotype of four SNPs including rs3811070. FUT9 codes for a fucosyl-transferase that is catalyzing the last step in the biosynthesis of the Lewis-x antigen, which forms part of the Lewis blood group-related antigens. These results therefore suggest an involvement of this antigen in the pathogenesis of placental malaria infection.

Impact of maternal human immunodeficiency virus infection on birth outcomes and infant survival in rural Mozambique

We assessed the effect of maternal human immunodeficiency virus (HIV) infection on birth outcomes and infant survival in rural Mozambique. Pregnant women attending the antenatal clinic were recruited. These women and their infants were followed-up for one year. Birth outcomes were assessed at delivery and infant HIV status was determined at 1 and 12 months of age. Women positive for HIV were more likely to have anemia at delivery than women negative for HIV (51.3% versus 35.4%; P < 0.001). Infants born to HIV-positive mothers had a significantly higher post-neonatal mortality rate than infants born to HIV-negative mothers (7.8% versus 1.9%; P < 0.001). The rate of transmission of HIV by breastfeeding during the first year of life was 15.1% (95% confidence interval = CI 7.6-22.4). Assessment of the impact of HIV infection on birth outcomes in rural Africa is essential for tailoring public health measures to reduce mother-to-child transmission of HIV and excess infant mortality.

Cost-effectiveness of malaria intermittent preventive treatment in infants (IPTi) in Mozambique and the United Republic of Tanzania

OBJECTIVE

To estimate the cost-effectiveness of malaria intermittent preventive treatment in infants (IPTi) using sulfadoxine-pyrimethamine (SP).

METHODS

In two previous IPTi trials in Ifakara (United Republic of Tanzania) and Manhiça (Mozambique), SP was administered three times to infants before 9 months of age through the Expanded Programme on Immunization. Based on the efficacy results of the intervention and on malaria incidence in the target population, an estimate was made of the number of clinical malaria episodes prevented. This number and an assumed case-fatality rate of 1.57% were used, in turn, to estimate the number of disability-adjusted life years (DALY) averted and the number of deaths averted. The cost of the intervention, including start-up and recurrent costs, was then assessed on the basis of these figures.

FINDINGS

The cost per clinical episode of malaria averted was US$ 1.57 (range: US$ 0.8-4.0) in Ifakara and US$ 4.73 (range: US$ 1.7-30.3) in Manhiça; the cost per DALY averted was US$ 3.7 (range: US$ 1.6-12.2) in Ifakara and US$ 11.2 (range: US$ 3.6-92.0) in Manhiça; and the cost per death averted was US$ 100.2 (range: US$ 43.0-330.9) in Ifakara and US$ 301.1 (range: US$ 95.6-2498.4) in Manhiça.

CONCLUSION

From the health system and societal perspectives, IPTi with SP is expected to produce health improvements in a cost-effective way. From an economic perspective, it offers good value for money for public health programmes.

Sub-microscopic infections and long-term recrudescence of Plasmodium falciparum in Mozambican pregnant women

Background

Control of malaria in pregnancy remains a public health challenge. Improvements in its correct diagnosis and the adequacy of protocols to evaluate anti-malarial drug efficacy in pregnancy, are essential to achieve this goal.

Methods

The presence of Plasmodium falciparum was assessed by real-time (RT) PCR in 284 blood samples from pregnant women with clinical complaints suggestive of malaria, attending the maternity clinic of a Mozambican rural hospital. Parasite recrudescences in 33 consecutive paired episodes during the same pregnancy were identified by msp1 and msp2 genotyping.

Results

Prevalence of parasitaemia by microscopy was 5.3% (15/284) and 23.2% (66/284) by RT-PCR. Sensitivity of microscopy, compared to RT-PCR detection, was 22.7%. Risk of maternal anaemia was higher in PCR-positive women than in PCR-negative women (odds ratio [OR] = 1.92, 95% confidence interval [CI] 1.09–3.36). Genotyping confirmed that recrudescence after malaria treatment occurred in 7 (21%) out of 33 pregnant women with consecutive episodes during the same pregnancy (time range between recrudescent episodes: 14 to 187 days).

Conclusion

More accurate and sensitive diagnostic indicators of malaria infection in pregnancy are needed to improve malaria control. Longer follow-up periods than the standard in vivo drug efficacy protocol should be used to assess anti-malarial drug efficacy in pregnancy.

A randomized placebo-controlled trial of intermittent preventive treatment in pregnant women in the context of insecticide treated nets delivered through the antenatal clinic

BACKGROUND

Current recommendations to prevent malaria in African pregnant women rely on insecticide treated nets (ITNs) and intermittent preventive treatment (IPTp). However, there is no information on the safety and efficacy of their combined use.

METHODS

1030 pregnant Mozambican women of all gravidities received a long-lasting ITN during antenatal clinic (ANC) visits and, irrespective of HIV status, were enrolled in a randomised, double blind, placebo-controlled trial, to assess the safety and efficacy of 2-dose sulphadoxine-pyrimethamine (SP). The main outcome was the reduction in low birth weight.

FINDINGS

Two-dose SP was safe and well tolerated, but was not associated with reductions in anaemia prevalence at delivery (RR, 0.92 [95% CI, 0.79-1.08]), low birth weight (RR, 0.99 [95% CI, 0.70-1.39]), or overall placental infection (p = 0.964). However, the SP group showed a 40% reduction (95% CI, 7.40-61.20]; p = 0.020) in the incidence of clinical malaria during pregnancy, and reductions in the prevalence of peripheral parasitaemia (7.10% vs 15.15%) (p<0.001), and of actively infected placentas (7.04% vs 13.60%) (p = 0.002). There was a reduction in severe anaemia at delivery of borderline statistical significance (p = 0.055). These effects were not modified by gravidity or HIV status. Reported ITN's use was more than 90% in both groups.

CONCLUSIONS

Two-dose SP was associated with a reduction in some indicators, but these were not translated to significant improvement in other maternal or birth outcomes. The use of ITNs during pregnancy may reduce the need to administer IPTp. ITNs should be part of the ANC package in sub-Saharan Africa.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00209781.

Clinical malaria in African pregnant women

BACKGROUND

There is a widespread notion, based on limited information, that in areas of stable malaria transmission most pregnant women with Plasmodium falciparum infection are asymptomatic. This study aim to characterize the clinical presentation of malaria in African pregnant women and to evaluate the adequacy of case management based on clinical complaints.

METHODS

A hospital-based descriptive study between August 2003 and November 2005 was conducted at the maternity clinic of a rural hospital in Mozambique. All women attending the maternity clinic were invited to participate. A total of 2,330 women made 3,437 eligible visits, 3129 were analysed, the remainder were excluded because diagnostic results were unavailable or they were repeat visits. Women gave a standardized clinical history and had a medical exam. Malaria parasitaemia and haematocrit in capillary blood was determined for all women with signs or symptoms compatible with malaria including: presence and history of fever, arthromyalgias, headache, history of convulsions and pallor. Outcome measure was association of malaria symptoms or signs with positive blood slide for malaria parasitaemia.

RESULTS

In 77.4% of visits pregnant women had symptoms suggestive of malaria; 23% (708/3129) were in the first trimester. Malaria parasitaemia was confirmed in 26.9% (842/3129) of visits. Headache, arthromyalgias and history of fever were the most common symptoms (86.5%, 74.8% and 65.4%) presented, but their positive predictive values for malaria parasitaemia were low [28% (27-30), 29% (28-31), and 33% (31-35), respectively].

CONCLUSION

Symptoms suggestive of malaria were very frequent among pregnant women attending a rural maternity clinic in an area of stable malaria transmission. However, less than a third of them were parasitaemic. In the absence of microscopy or rapid diagnostic tests, a large proportion of women, including those in the first trimester of gestation, would be unnecessarily receiving antimalarial drugs, often those with unknown safety profiles for pregnancy. Accessibility to malaria diagnostic tools needs to be improved for pregnant women and drugs with a safety profile in all gestational ages are urgently needed.

Safety of the RTS,S/AS02D candidate malaria vaccine in infants living in a highly endemic area of Mozambique: a double blind randomised controlled phase I/IIb trial

BACKGROUND

Malaria remains a leading global health problem that requires the improved use of existing interventions and the accelerated development of new control methods. We aimed to assess the safety, immunogenicity, and initial efficacy of the malaria vaccine RTS,S/AS02D in infants in Africa.

METHODS

We did a phase I/IIb double-blind randomised trial of 214 infants in Mozambique. Infants were randomly assigned to receive three doses either of RTS,S/AS02D or the hepatitis B vaccine Engerix-B at ages 10 weeks, 14 weeks, and 18 weeks of age, as well as routine immunisation vaccines given at 8, 12, and 16 weeks of age. The primary endpoint was safety of the RTS,S/AS02D during the first 6 months of the study, and analysis was by intention to treat. Secondary endpoints included immunogenicity and analysis of new Plasmodium falciparum infections during a 3-month follow up after the third dose. Time to new infections in the per-protocol cohort were compared between groups using Cox regression models. This study is registered with ClinicalTrials.gov, number NCT00197028.

FINDINGS

There were 17 children (15.9%; 95% CI 9.5-24.2) with serious adverse events in each group. In the follow-up which ended on March 6, 2007, there were 31 serious adverse events in the RTS,S/AS02D group and 30 serious adverse events in the Engerix-B group, none of which were reported as related to vaccination. There were four deaths during this same follow-up period; all of them after the active detection of infection period had finished at study month 6 (two in RTSS/AS02D group and two in the Engerix-B group). RTS,S/AS02D induced high titres of anti-circumsporozoite antibodies. 68 first or only P falciparum infections were documented: 22 in the RTS,S/AS02D group and 46 in the control group. The adjusted vaccine efficacy was 65.9% (95% CI 42.6-79.8%, p<0.0001).

INTERPRETATION

The RTS,S/AS02D malaria vaccine was safe, well tolerated, and immunogenic in young infants. These findings set the stage for expanded phase III efficacy studies to confirm vaccine efficacy against clinical malaria disease.

Sequential multiplex PCR for identifying pneumococcal capsular serotypes from South-Saharan African clinical isolates

A serial multiplex PCR approach was reformulated for pneumococcal serotyping to test 153 clinical isolates from children in Mozambique. This approach identified serotypes in 139 (90.8%) of 153 isolates; 126 (82.4%) were identified within two reactions. This approach in developing countries would require minimal training and could provide useful serotype information without requiring transport of specimens.

Intermittent preventive treatment for malaria control administered at the time of routine vaccinations in Mozambican infants: a randomized, placebo-controlled trial

BACKGROUND

There is an urgent need to deploy and develop new control tools that will reduce the intolerable burden of malaria. Intermittent preventive treatment in infants (IPTi) has the potential to become an effective tool for malaria control.

METHODS

We performed a randomized, double-blind, placebo-controlled trial of sulfadoxine-pyrimethamine (SP) treatment in 1503 Mozambican children. Doses of SP or placebo were given at 3, 4, and 9 months of age. The intervention was administered alongside routine vaccinations delivered through the Expanded Program on Immunization (EPI). Hematological and biochemical tests were done when infants were 5 months old. Morbidity monitoring through a hospital-based passive case-detection system was complemented by cross-sectional surveys when infants were 12 and 24 months old.

RESULTS

IPTi was well tolerated, and no adverse events associated with SP were documented. During the first year of life, intermittent SP treatment reduced the incidence of clinical malaria by 22.2% (95% confidence interval [CI], 3.7%-37.0%; P=.020) and the rate of hospital admissions by 19% (95% CI, 4.0%-31.0%; P=.014). Although the incidence of severe anemia (packed cell volume of <25%) did not differ significantly between the 2 groups (protective effect, 12.7% [95% CI, -17.3% to 35.1%]; P=.36), there was a significant reduction in hospital admissions for anemia during the month after dosing for both the first and second dose. The serological responses to EPI vaccines were not modified by the intervention.

CONCLUSIONS

IPTi with SP has been shown to moderately reduce the incidence of clinical malaria in Mozambican infants without evidence of rebound after stopping the intervention or of interactions with EPI vaccines. Its recommendation as a malaria control strategy in Mozambique needs to be balanced against the scarcity of affordable control tools and the burden of malaria in children.

Duration of protection with RTS,S/AS02A malaria vaccine in prevention of Plasmodium falciparum disease in Mozambican children: single-blind extended follow-up of a randomised controlled trial

BACKGROUND

RTS,S/AS02A is a pre-erythrocytic stage malaria vaccine that provides partial protection against infection in malaria-naive adult volunteers and hyperimmune adults. A previous report showed that this vaccine reduced risk of clinical malaria, delayed time to new infection, and reduced episodes of severe malaria over 6 months in African children. An important remaining issue is the durability of protection against clinical disease in these children.

METHODS

We did a randomised, controlled, phase IIb trial of RTS,S/AS02A given at 0, 1, and 2 months in 2022 Mozambican children aged 1-4 years. We previously determined vaccine efficacy (VE) against clinical malaria in a double-blind phase that included study months 2.5-8.5 (VE(2.5-8.5)). We now report VE in a single-blind phase up to month 21 (VE(8.5-21)). The primary endpoint was time to first or only clinical episode of Plasmodium falciparum malaria (axillary temperature 37.5 degrees C and P falciparum asexual parasitaemia >2500 per microL) detected through a passive case detection system. We also determined VE for other case definitions and for episodes of severe malaria. This study is registered with the ClinicalTrials.gov identifier NCT00197041.

FINDINGS

During the single-blind phase, VE(8.5-21) was 28.9% (95% CI 8.4-44.8; p=0.008). At month 21, prevalence of P falciparum infection was 29% lower in the RTS,S/AS02A group than in the control (p=0.017). Considering the entire study period, VE(2.5-21) was 35.3% (95% CI 21.6-46.6; p<0.0001) and VE(2.5-21) for severe malaria was 48.6% (95% CI 12.3-71.0; p=0.02).

INTERPRETATION

These results show that RTS,S/AS02A confers partial protection in African children aged 1-4 years living in rural endemic areas against a range of clinical disease caused by P falciparum for at least 18 months, and confirm the potential of malaria vaccines to become credible control tools for public-health use.