Diversity of Glossinidae (Diptera) species in The Gambia in relation to vegetation.

Glossina species are known to transmit African Trypanosomiasis, one of the most important infectious diseases for both livestock and humans in sub-Saharan Africa. Therefore, the aim of this study was to characterize trapped Glossina spp. from The Gambia using morphological and molecular techniques in relation to the vegetation cover types. A line transect survey was carried out in all the administrative regions of The Gambia. Tsetse fly trapping was carried out for 14 days during each season using line transect. A total of 220 Glossina spp. specimens (117 F and 103 M) were captured, and DNA was extracted from the legs of 100 randomly selected Glossina spp. Further, DNA samples were tested by a conventional PCR assay. A total of 135/220 (61%; 95% CI: 54.6-67.8%) and 85/220 (39%; 95% CI: 32.2-45.4%) flies were identified as Glossina morsitans submorsitans and Glossina palpalis gambiensis, respectively, with most caught during wet season (53.6%) and more females (53.2%) than males. Results of the morphological identification agreed with those of molecular identification. The type of vegetation cover significantly influenced the caught of tsetse flies. Animals and humans at the various trapping sites are at risk of being bitten by tsetse flies.

Comparison of Two Approaches for the Metataxonomic Analysis of the Human Milk Microbiome.

Recent work has demonstrated the existence of large inter-individual and inter-population variability in the microbiota of human milk from healthy women living across variable geographical and socio-cultural settings. However, no studies have evaluated the impact that variable sequencing approaches targeting different 16S rRNA variable regions may have on the human milk microbiota profiling results. This hampers our ability to make meaningful comparisons across studies. In this context, the main purpose of the present study was to re-process and re-sequence the microbiome in a large set of human milk samples (n = 412) collected from healthy women living at diverse international sites (Spain, Sweden, Peru, United States, Ethiopia, Gambia, Ghana and Kenya), by targeting a different 16S rRNA variable region and reaching a larger sequencing depth. Despite some differences between the results obtained from both sequencing approaches were notable (especially regarding alpha and beta diversities and Proteobacteria representation), results indicate that both sequencing approaches revealed a relatively consistent microbiota configurations in the studied cohorts. Our data expand upon the milk microbiota results we previously reported from the INSPIRE cohort and provide, for the first time across globally diverse populations, evidence of the impact that different DNA processing and sequencing approaches have on the microbiota profiles obtained for human milk samples. Overall, our results corroborate some similarities regarding the microbial communities previously reported for the INSPIRE cohort, but some differences were also detected. Understanding the impact of different sequencing approaches on human milk microbiota profiles is essential to enable meaningful comparisons across studies. Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT02670278.

Multipathogen Analysis of IgA and IgG Antigen Specificity for Selected Pathogens in Milk Produced by Women From Diverse Geographical Regions: The INSPIRE Study.

Breastfeeding provides defense against infectious disease during early life. The mechanisms underlying this protection are complex but likely include the vast array of immune cells and components, such as immunoglobulins, in milk. Simply characterizing the concentrations of these bioactives, however, provides only limited information regarding their potential relationships with disease risk in the recipient infant. Rather, understanding pathogen and antigen specificity profiles of milk-borne immunoglobulins might lead to a more complete understanding of how maternal immunity impacts infant health and wellbeing. Milk produced by women living in 11 geographically dispersed populations was applied to a protein microarray containing antigens from 16 pathogens, including diarrheagenic E. coli, Shigella spp., Salmonella enterica serovar Typhi, Staphylococcus aureus, Streptococcus pneumoniae, Mycobacterium tuberculosis and other pathogens of global health concern, and specific IgA and IgG binding was measured. Our analysis identified novel disease-specific antigen responses and suggests that some IgA and IgG responses vary substantially within and among populations. Patterns of antibody reactivity analyzed by principal component analysis and differential reactivity analysis were associated with either lower-to-middle-income countries (LMICs) or high-income countries (HICs). Antibody levels were generally higher in LMICs than HICs, particularly for Shigella and diarrheagenic E. coli antigens, although sets of S. aureus, S. pneumoniae, and some M. tuberculosis antigens were more reactive in HICs. Differential responses were typically specific to canonical immunodominant antigens, but a set of nondifferential but highly reactive antibodies were specific to antigens possibly universally recognized by antibodies in human milk. This approach provides a promising means to understand how breastfeeding and human milk protect (or do not protect) infants from environmentally relevant pathogens. Furthermore, this approach might lead to interventions to boost population-specific immunity in at-risk breastfeeding mothers and their infants.

Estimating access to drinking water and sanitation: The need to account for uncertainty in trend analysis.

Nationally representative household surveys are the main source of data for tracking drinking water, sanitation and hygiene (WASH) coverage. However, all survey point estimates have a certain degree of error that must be considered when interpreting survey results for policy and decision making. In this article, we develop an approach to characterize and quantify uncertainty around WASH estimates. We apply it to four countries - Bolivia, Gambia, Morocco and India - representing different regions, number of data points available and types of trajectories, in order to illustrate the importance of communicating uncertainty for temporal estimates, as well as taking into account both the compositional nature and non-linearity of JMP data. The approach is found to be versatile and particularly useful in the WASH sector, where the dissemination and analysis of standard errors lag behind. While it only considers the uncertainty arising from sampling, the proposed approach can help improve the interpretation of WASH data when evaluating trends in coverage and informing decision making.

Evidence for supercoughers in an analysis of six tuberculosis cohorts from China, Peru, The Gambia and Uganda.

BACKGROUND: It is very difficult to observe tuberculosis (TB) transmission chains and thus, identify superspreaders. We investigate cough duration as a proxy measure of transmission to assess the presence of potential TB superspreaders.DESIGN: We analyzed six studies from China, Peru, The Gambia and Uganda, and determined the distribution of cough duration and compared it with several theoretical distributions. To determine factors associated with cough duration, we used linear regression and boosted regression trees to examine the predictive power of patient, clinical and environmental characteristics.RESULTS: We found within-study heterogeneity in cough duration and strong similarities across studies. Approximately 20% of patients contributed 50% of total cough days, and around 50% of patients contributed 80% of total cough days. The cough duration distribution suggested an initially increasing, and subsequently, decreasing hazard of diagnosis. While some of the exposure variables showed statistically significant associations with cough duration, none of them had a strong effect. Multivariate analyses of different model types did not produce a model that had good predictive power.CONCLUSION: We found consistent evidence for the presence of supercoughers, but no characteristics predictive of such individuals.

Primer reporte de necrólisis epidérmica tóxica por antibiótico oral en Gambia / First report of toxic epidermal necrolysis due to oral antibiotic in Gambia

Las reacciones adversas medicamentosas más frecuentes son las cutáneas, ocurriendo en un 2% de los tratamientos. La mayoría de las veces se alcanza el diagnóstico por exclusión. La más temida es la necrólisis epidérmica tóxica, de la que se presentan anualmente hasta 4 casos por millón de habitantes, con una mortalidad que alcanza en ocasiones hasta el 70 %. El objetivo fue presentar un paciente con necrólisis epidérmica tóxica por lo infrecuente de esta enfermedad, su alta mortalidad y su evolución clínica característica. Paciente gambiano, de 29 años de edad, con antecedentes de salud, que después de comenzar tratamiento ambulatorio con antibiótico oral para una piodermitis facial, presentó lesiones ampollares que se extendieron por todo el cuerpo. El paciente llevó tratamiento de sostén, esteroideo oral, antibiótico de amplio espectro oral, parenteral y tópico; después de una evolución desfavorable de 30 días, fallece. Resultó llamativa la ausencia de lesiones mucosas a pesar de la extensión total de las lesiones cutáneas. Fue difícil el manejo de este paciente en un hospital de periferia sin el arsenal terapéutico adecuado, ni la unidad idónea para su cuidado (AU).

The most frequent drug adverse reactions are the skin ones, occurring in 2 % of the treatments; most of the times the diagnosis is reached by exclusion. The most feared one is the toxic epidermal necrolysis, presenting yearly up to 4 cases per million of inhabitants with a mortality occasionally reaching 70 %. The objective was presenting the case of a patient with toxic epidermal necrolysis because of the rarity of this disease, its high mortality and characteristic clinical evolution. The patient was a Gambian aged 29 years, with health antecedents, who after beginning an outpatient treatment with oral antibiotic for a facial pyodermitis, presented bullous lesions extended throughout all the body. The patient received support treatment, oral steroidal treatment and oral, parenteral and topic treatment with a wide spectrum antibiotic; after a 30-days unfavorable evolution, he died. It was thought-provoking the absence of mucous lesions in spite of the total extension of the skin lesions. It was difficult the management of this patient in a peripheral hospital without the adequate therapeutic arsenal nor the suitable unit for his care (AU).

Linking national wood consumption with global biodiversity and ecosystem service losses.

Identifying the global hotspots of forestry driven species, ecosystem services losses and informing the consuming nations of their environmental footprint domestically and abroad is essential to design demand side interventions and induce sustainable production methods. Here we first use countryside species area relationship model to project species extinctions of four vertebrate taxa (mammals, birds, amphibians and reptiles) due to forest land use in 174 countries. We combine the projected extinctions with a global database on the monetary value of ecosystem services provided by different biomes and with bilateral trade data of wood products to calculate species extinctions and ecosystem services losses inflicted by national wood consumption and international wood trade. Results show that globally a total of 485 species are projected to go extinct due to current forest land use. About 32% of this projected loss can be attributed to land use devoted for export production. However, under the counterfactual scenario with the same consumption levels but no international trade of wood products, an additional 334 species are projected to go extinct. Globally, we find that losses of ecosystem services worth $1.5trillion/year are embodied in the timber trade. Compared to high-income nations, tropical countries such as Philippines, Nicaragua, Sri Lanka, Gambia and Bolivia presented the highest net ecosystem services losses (>3000US$/ha/year) that could not be compensated through current land rents, indicating underpriced exports. Small tropical countries also gained much lower rents per species extinction suffered. These results can help internalize these costs into the global trade through financial compensation mechanisms such as REDD+ or through price premiums on wood sourced from these countries. Overall the results can provide valuable insights for devising national strategies to meet several of the global Aichi 2020 biodiversity targets and can also be useful for life cycle assessment and product labelling schemes.

Incidence of Haemophilus influenzae type b disease in The Gambia 14 years after introduction of routine Haemophilus influenzae type b conjugate vaccine immunization.

OBJECTIVE: Haemophilus influenzae type b (Hib) conjugate vaccine was first introduced in Africa in The Gambia in 1997 as a primary 3-dose course in infancy with no booster, and was followed by the disappearance of invasive Hib disease by 2002. A cluster of cases detected non-systematically in post-infant children in 2005-2006 raised the question of the need for a booster dose. The objective of this study was to determine the incidence of invasive Hib disease in Gambian children 14 years after the introduction of Hib conjugate vaccine. STUDY DESIGN: This hospital-based clinical and microbiological Hib disease surveillance in 3 hospitals in the western region of The Gambia was undertaken between October 2007 and December 2010 applying the same methods used in a previous Hib vaccine effectiveness study in 1997-2002. RESULTS: The annual incidences of Hib meningitis and all invasive Hib disease in children aged <5 years remained below 5 cases per 100,000 children during 2008-2010. The median age of patients with any invasive Hib disease was 5 months. CONCLUSION: Hib conjugate vaccination as a primary 3-dose course in The Gambia remains highly effective in controlling invasive Hib disease, and current data do not support the introduction of a booster dose.

Critical windows for nutritional interventions against stunting.

An analysis of early growth patterns in children from 54 resource-poor countries in Africa and Southeast Asia shows a rapid falloff in the height-for-age z score during the first 2 y of life and no recovery until ≥5 y of age. This finding has focused attention on the period -9 to 24 mo as a window of opportunity for interventions against stunting and has garnered considerable political backing for investment targeted at the first 1000 d. These important initiatives should not be undermined, but the objective of this study was to counteract the growing impression that interventions outside of this period cannot be effective. We illustrate our arguments using longitudinal data from the Consortium of Health Oriented Research in Transitioning collaboration (Brazil, Guatemala, India, Philippines, and South Africa) and our own cross-sectional and longitudinal growth data from rural Gambia. We show that substantial height catch-up occurs between 24 mo and midchildhood and again between midchildhood and adulthood, even in the absence of any interventions. Longitudinal growth data from rural Gambia also illustrate that an extended pubertal growth phase allows very considerable height recovery, especially in girls during adolescence. In light of the critical importance of maternal stature to her children's health, our arguments are a reminder of the importance of the more comprehensive UNICEF/Sub-Committee on Nutrition Through the Life-Cycle approach. In particular, we argue that adolescence represents an additional window of opportunity during which substantial life cycle and intergenerational effects can be accrued. The regulation of such growth is complex and may be affected by nutritional interventions imposed many years previously.

Modelo de atención a la malnutrición crónica infantil en la región de Upper River, Gambia, según el marco Innovative Care for Chronic Conditions / Attention Model to chronic child malnutrition in the region of Upper River, Gambia, according to the Innovative framework Care for Chronic Conditions / Modelo de atenção à malnutrição crônica infantil na região de Upper River, Gâmbia, segundo o quadro Innovative Care for Chronic Conditions

La malnutrición es uno de los principales problemas de salud pública en la República de Gambia,con un 18 % de la población menor de cinco años afectada. El objetivo de este trabajo esofrecer una descripción y un análisis del conjunto de actores e instituciones y de sus políticase intervenciones involucradas en el abordaje de la malnutrición crónica infantil en la región deUpper River, Gambia. El mapa de atención a la malnutrición infantil se ha realizado a partirde una evaluación del modelo de atención vigente, siguiendo la herramienta Innovative Carefor Chronic Conditions Framework Situation Assessment de la Organización Mundial de laSalud, guiando el análisis por la experiencia profesional en este contexto del autor, y con elapoyo de la bibliografía consultada. Basado en los resultados, a modo de discusión se ofreceuna serie de intervenciones y estrategias de mejora del modelo en sus tres niveles de atencióna la malnutrición infantil...

Malnutrition is a major public health problem in the Republic of Gambia, with 18% of the populationunder five affected. The purpose of this paper is to provide a description and analysis of theset of actors and institutions, their policies and interventions involved in tackling child chronicmalnutrition in the region of Upper River, Gambia. The map of attention to child malnutritionhas been made from an assessment of the current care model, following the tool InnovativeCare for Chronic Conditions Framework Situation Assessment of the World Health Organization,guiding the analysis by professional experience in this context of the author, and with thesupport of the consulted bibliography. Based on the results, a series of interventions and strategiesfor improvement of the model in its three levels of care to child malnutrition is discussed...

A malnutrição é um dos principais problemas de saúde pública na República de Gâmbia, com um18 % da população menor de cinco anos afetada. O objetivo deste trabalho é oferecer descriçãoe análise do conjunto de atores e instituições e das suas políticas e intervenções envolvidasna abordagem da malnutrição crônica infantil na região de Upper River, Gâmbia. O mapa deatenção à malnutrição infantil realizou-se a partir de uma avaliação do modelo de atençãovigente, seguindo a ferramenta Innovative Care for Chronic Conditions Framework SituationAssessment da Organização Mundial da Saúde, guiando a análise pela experiência profissionalneste contexto do autor, e com apoio da bibliografia consultada. Baseado nos resultados, a modode discussão oferece-se uma série de intervenções e estratégias de melhoramento do modeloem seus três níveis de atenção à malnutrição infantil...

MCP1 SNPs and pulmonary tuberculosis in cohorts from West Africa, the USA and Argentina: lack of association or epistasis with IL12B polymorphisms.

The monocyte chemotactic protein-1 (MCP-1) is a chemokine that plays an important role in the recruitment of monocytes to M. tuberculosis infection sites, and previous studies have reported that genetic variants in MCP1 are associated with differential susceptibility to pulmonary tuberculosis (PTB). We examined eight MCP1 single nucleotide polymorphisms (SNPs) in a multi-ethnic, case-control design that included: 321 cases and 346 controls from Guinea-Bissau, 258 cases and 271 controls from The Gambia, 295 cases and 179 controls from the U.S. (African-Americans), and an additional set of 237 cases and 144 controls of European ancestry from the U.S. and Argentina. Two locus interactions were also examined for polymorphisms in MCP1 and interleukin 12B (IL12B), another gene implicated in PTB risk. Examination of previously associated MCP1 SNPs rs1024611 (-2581A/G), rs2857656 (-362G/C) and rs4586 (+900C/T) did not show evidence for association. One interaction between rs2857656 and IL12B SNP rs2288831 was observed among Africans but the effect was in the opposite direction in Guineans (OR = 1.90, p = 0.001) and Gambians (OR = 0.64, p = 0.024). Our data indicate that the effect of genetic variation within MCP1 is not clear cut and additional studies will be needed to elucidate its role in TB susceptibility.

Organization and startup of The Gambia's new community-based medical programme.

The shortage of health professionals in developing countries and especially in their poorest regions imperils the vision of health for all. New training policies and strategies are needed urgently to address these shortages. The Gambia's new Community-Based Medical Programme is one such strategy. KEYWORDS Medical education, access to health care, healthcare disparities, health manpower, rural health, developing countries, The Gambia.

Interleukin 12B (IL12B) genetic variation and pulmonary tuberculosis: a study of cohorts from The Gambia, Guinea-Bissau, United States and Argentina.

We examined whether polymorphisms in interleukin-12B (IL12B) associate with susceptibility to pulmonary tuberculosis (PTB) in two West African populations (from The Gambia and Guinea-Bissau) and in two independent populations from North and South America. Nine polymorphisms (seven SNPs, one insertion/deletion, one microsatellite) were analyzed in 321 PTB cases and 346 controls from Guinea-Bissau and 280 PTB cases and 286 controls from The Gambia. For replication we studied 281 case and 179 control African-American samples and 221 cases and 144 controls of European ancestry from the US and Argentina. First-stage single locus analyses revealed signals of association at IL12B 3' UTR SNP rs3212227 (unadjusted allelic p = 0.04; additive genotypic p = 0.05, OR = 0.78, 95% CI [0.61-0.99]) in Guinea-Bissau and rs11574790 (unadjusted allelic p = 0.05; additive genotypic p = 0.05, OR = 0.76, 95% CI [0.58-1.00]) in The Gambia. Association of rs3212227 was then replicated in African-Americans (rs3212227 allelic p = 0.002; additive genotypic p = 0.05, OR = 0.78, 95% CI [0.61-1.00]); most importantly, in the African-American cohort, multiple significant signals of association (seven of the nine polymorphisms tested) were detected throughout the gene. These data suggest that genetic variation in IL12B, a highly relevant candidate gene, is a risk factor for PTB in populations of African ancestry, although further studies will be required to confirm this association and identify the precise mechanism underlying it.

Conference on "Multidisciplinary approaches to nutritional problems". Postgraduate Symposium. Exploiting dietary supplementation trials to assess the impact of the prenatal environment on CVD risk.

Animal studies have demonstrated that altering the maternal diet during pregnancy affects offspring disease risk. Data from human subjects on the early-life determinants of disease have been derived primarily from birth-weight associations; studies of the impact of the maternal diet are scarce and inconsistent. Investigating CVD risk factors in the offspring of women who have participated in maternal supplementation trials provides a useful resource in this research field, by virtue of employing an experimental design (as compared with observational studies). To date, follow-up studies have been published only for a small number of trials; these trials include the impact of maternal protein-energy, multiple-micronutrient and Ca supplementation on offspring disease risk. In Nepal maternal micronutrient supplementation has been shown to be associated with lower offspring systolic blood pressure at 2 years of age. Data from Guatemala on a pre- and postnatal protein-energy community intervention have suggested long-term improvements in fasting glucose and body composition but not in blood pressure. In The Gambia no association has been found between prenatal protein-energy supplementation and markers of CVD risk including body composition, blood pressure and fasting glucose and insulin in childhood and adolescence. Little evidence of an effect of maternal Ca supplementation on offspring blood pressure has been demonstrated in four trials, although the risk of high systolic blood pressure was found to be reduced in one trial. The present paper reviews the current evidence relating maternal nutritional supplementation during pregnancy to offspring CVD risk and explores the potential explanations for the lack of association.

Classical sickle beta-globin haplotypes exhibit a high degree of long-range haplotype similarity in African and Afro-Caribbean populations.

BACKGROUND: The sickle (betas) mutation in the beta-globin gene (HBB) occurs on five "classical" betas haplotype backgrounds in ethnic groups of African ancestry. Strong selection in favour of the betas allele - a consequence of protection from severe malarial infection afforded by heterozygotes - has been associated with a high degree of extended haplotype similarity. The relationship between classical betas haplotypes and long-range haplotype similarity may have both anthropological and clinical implications, but to date has not been explored. Here we evaluate the haplotype similarity of classical betas haplotypes over 400 kb in population samples from Jamaica, The Gambia, and among the Yoruba of Nigeria (Hapmap YRI). RESULTS: The most common betas sub-haplotype among Jamaicans and the Yoruba was the Benin haplotype, while in The Gambia the Senegal haplotype was observed most commonly. Both subtypes exhibited a high degree of long-range haplotype similarity extending across approximately 400 kb in all three populations. This long-range similarity was significantly greater than that seen for other haplotypes sampled in these populations (P < 0.001), and was independent of marker choice and marker density. Among the Yoruba, Benin haplotypes were highly conserved, with very strong linkage disequilibrium (LD) extending a megabase across the betas mutation. CONCLUSION: Two different classical betas haplotypes, sampled from different populations, exhibit comparable and extensive long-range haplotype similarity and strong LD. This LD extends across the adjacent recombination hotspot, and is discernable at distances in excess of 400 kb. Although the multi-centric geographic distribution of betas haplotypes indicates strong subdivision among early Holocene sub-Saharan populations, we find no evidence that selective pressures imposed by falciparum malaria varied in intensity or timing between these subpopulations. Our observations also suggest that cis-acting loci, which may influence outcomes in sickle cell disease, could lie considerable distances away from beta-globin.

Evolution of bird eggs in the absence of cuckoo parasitism.

Historical introductions of species into new habitats can create rare opportunities to test evolutionary hypotheses, such as the role of natural selection in maintaining traits. This study examines two independent introductions of the African village weaverbird (Ploceus cucullatus) to islands where selection on egg appearance traits is expected to differ markedly from that of the source populations. The color and spotting of village weaver eggs in Africa are highly consistent within clutches, but highly variable between individuals. These two features may be an evolutionary response to brood parasitism. In Africa, weavers are parasitized by each other and by the diederik cuckoo (Chrysococcyx caprius), an egg mimic. African village weavers were introduced one century ago to Mauritius, and over two centuries ago to Hispaniola. Both islands are devoid of egg-mimicking brood parasites. In these two populations, between-individual variation and within-clutch consistency in egg appearance have both decreased, as has the incidence of spotting, relative to the source populations in Africa. These reductions are more pronounced on Hispaniola, the earlier introduction. Such changes support the hypothesis that egg appearance in the African village weaver has been maintained by natural selection as a counteradaptation to cuckoo brood parasitism. These results illustrate that the removal of an agent of selection can sometimes bring about rapid evolutionary consequences.

Respiratory illness after severe respiratory syncytial virus disease in infancy in The Gambia.

OBJECTIVE: To determine the frequency of later respiratory tract morbidity after respiratory syncytial virus (RSV) disease in infancy. DESIGN: Cohort study with passive, clinic-based surveillance. SETTING: Outpatient department in The Gambia. SUBJECTS: One hundred five children admitted to the hospital with severe RSV disease (case cohort), 105 control children matched for age not admitted to the hospital during the previous RSV season (control cohort 1), and 102 control children born after the RSV season (control cohort 2). MAIN OUTCOME MEASURES: Frequencies of pneumonia, wheezing, and hospital admission with acute lower respiratory tract infection. RESULTS: Pneumonia was more common in case children than in both control groups (adjusted incidence rate ratio [IRR, 95% CI]: 3.80 [2.73, 6. 10]), as was wheezing (IRR 7.33 [3.10,17.54]), pneumonia or wheezing (IRR 3.96 [2.60, 6.04]), and admission with pneumonia or wheezing (IRR 3.40 [1.87, 6.15]). The incidence rate per 100 child-years for pneumonia in the dry season for 12-month-old children was 27 for case patients, 8.1 for control cohort 1, and 6.51 for control cohort 2. By 3 years of age, the rates had fallen to low levels in all groups. CONCLUSIONS: Pneumonia and wheezing are significantly more common in children after RSV-associated lower respiratory tract disease than in control subjects, but the incidence declines rapidly with increasing age.

Evaluation of vaccines for the prevention of pneumonia in children in developing countries.

PIP: This paper evaluates vaccines designed to prevent pneumonia among children in developing countries. Additionally, the article discusses the measurement of vaccine efficacy, as well as the potential of vaccine trials to provide information on the etiology of pneumonia and the need for an antibiotic treatment for various categories of acute respiratory infections (ARI). The three approaches to pneumococcal vaccine development include: 1) polysaccharide vaccines; 2) protein-polysaccharide conjugate vaccines; and 3) vaccines based on common protein antigens. The trial design was performed by individual randomization and randomization in clusters. Vaccines were evaluated in terms of the protection they provide against diseases with an unknown pathogen. The clinical and radiologic evaluation of pneumococcal vaccine trials served three related functions: 1) defining the ability of the vaccines to prevent severe pneumonia; 2) measuring the impact of the vaccine on the total burden of pneumonia that is defined by the World Health Organization; and 3) subdividing documented ARI episodes along clinical and radiological lines. Pneumococcal vaccine trials are essential in understanding the nature of pneumococcal disease among children in developing countries, as well as the public health utility of vaccines for its prevention.^ieng