Malaria Prevention with IPTp during Pregnancy Reduces Neonatal Mortality

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.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.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].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.ClinicalTrials.gov NCT00209781

Clinical malaria in African pregnant women

<p>Abstract</p> <p>Background</p> <p>There is a widespread notion, based on limited information, that in areas of stable malaria transmission most pregnant women with <it>Plasmodium falciparum </it>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.</p> <p>Methods</p> <p>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.</p> <p>Results</p> <p>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].</p> <p>Conclusion</p> <p>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.</p

Prevalence and Risk Factors of Sexually Transmitted Infections and Cervical Neoplasia in Women from a Rural Area of Southern Mozambique

There is limited information on the prevalence of sexually transmitted infections and the prevalence of cervical neoplasia in rural sub-Saharan Africa. This study describes the prevalence and the etiology of STIs and the prevalence of cervical neoplasia among women in southern Mozambique. An age-stratified cross-sectional study was performed where 262 women aged 14 to 61 years were recruited at the antenatal clinic (59%), the family-planning clinic (7%), and from the community (34%). At least one active STI was diagnosed in 79% of women. Trichomonas vaginalis was present in 31% of all study participants. The prevalence of Neisseria gonorrhea and Chlamydia trachomatis were 14% and 8%, respectively, and Syphilis was diagnosed in 12% of women. HPV DNA was detected in 40% of women and cervical neoplasia was diagnosed in 12% of all women. Risk factors associated with the presence of some of the STIs were being divorced or widowed, having more than one sexual partner and having the partner living in another area. A higher prevalence was observed in the reproductive age group and some of the STIs were more frequently diagnosed in pregnant women. STI control programs are a priority to reduce the STIs burden, including HIV and cervical neoplasia

Impact of Maternal Human Immunodeficiency Virus Infection on Birth Outcomes and Infant Survival in Rural Mozambique

Sub-Saharan Africa harbors more than two-thirds of the world’s 33.2 million persons infected with human immunodeficiency virus (HIV) and 80% of the world’s HIV-infected women. In parts of southern Africa, more than 30% of pregnant women attending antenatal clinics are infected with HIV, thus making HIV infection one of the most common complications of pregnancy in sub-Saharan Africa. With successful interventions, mother-to-child transmission (MTCT) of HIV has been reduced to less than 2% in developed countries. However, in untreated populations, MTCT of HIV during pregnancy, delivery, and breastfeeding still occurs at an approximate overall rate of 25–40%, and accounts for almost 420,000 new HIV infections in children and 270,000–320,000 pediatric deaths annually. Until 2004, single-dose intrapartum and neonatal nevirapine (sd-NVP) was the recommended regimen by the World Health Organization to prevent MTCT of HIV among women without access to antiretroviral therapy. Preventive MTCT programs with an sd-NVP have been shown to decrease perinatal HIV transmission to 8% in controlled clinical trial settings. However, there is great concern about the rapid development of resistance. In addition, in predominantly breastfeeding populations of sub- Saharan Africa, most MTCT of HIV still occurs during the postnatal period. Currently, MTCT prevention programs in sub-Saharan African countries include zidovudine and lamivudine during the final weeks of pregnancy and sd-NVP at delivery. In addition, the newborn receives sd-NVP at birth and zidovudine for seven days. Nevertheless, effectiveness of these strategies relies on the great challenge of availability of the drugs and compliance with them, given that these preventive regimens are prolonged and unsupervised. Several studies from the Africa have reported that HIVinfected pregnant women are at increased risk of adverse pregnancy outcomes such as spontaneous abortion, stillbirths, and preterm labor. However, this analysis is complicated by many factors associated with HIV infection and poor pregnancy outcomes such as malnutrition, anemia, and other frequent infections such as syphilis or malaria. These factors may contribute to the observation that the association between HIV infection and adverse pregnancy outcomes is stronger in women from developing countries. Maternal HIV infection has also been associated with an increased risk of infant death. It is well documented that up to 35% of HIV-infected infants may die before the first year of age, but HIV-negative children born to HIV-infected mothers are also at high risk of mortality. There have been few studies characterizing the impact of HIV infection during pregnancy on the mother and her infant and even fewer from rural African settings. The main aim of this study was to assess the impact of HIV infection on birth outcomes and infant survival in a rural area of southern Mozambique. Furthermore, the study also evaluated the effect of unsupervised sd-NVP administration for prevention of MTCT of HIV on HIV RNA viral load at delivery and the prevalence of NVP resistance mutations

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 dissemi-nation 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.Fil: Gladstone, Rebecca A.. Wellcome Sanger Institute; Reino UnidoFil: Lo, Stephanie W.. Wellcome Sanger Institute; Reino UnidoFil: Goater, Richard. Wellcome Sanger Institute; Reino Unido. University of Oxford; Reino UnidoFil: Yeats, Corin. Wellcome Sanger Institute; Reino Unido. University of Oxford; Reino UnidoFil: Taylor, Ben. Wellcome Sanger Institute; Reino Unido. University of Oxford; Reino UnidoFil: Hadfield, James. Fred Hutchinson Cancer Research Center; Estados UnidosFil: Lees, John A.. Imperial College London; Reino UnidoFil: Croucher, Nicholas J.. Imperial College London; Reino UnidoFil: van Tonder, Andries. Wellcome Sanger Institute; Reino Unido. University of Cambridge; Estados UnidosFil: Bentley, Leon J.. Wellcome Sanger Institute; Reino UnidoFil: Quah, Fu Xiang. Wellcome Sanger Institute; Reino UnidoFil: Blaschke, Anne J.. University of Utah; Estados UnidosFil: Pershing, Nicole L.. University of Utah; Estados UnidosFil: Byington, Carrie L.. University of California; Estados UnidosFil: Balaji, Veeraraghavan. Christian Medical College; IndiaFil: Hryniewicz, Waleria. National Medicines Institute; PoloniaFil: Sigauque, Betuel. Instituto Nacional de Saude Maputo; MozambiqueFil: Ravikumar, K. L.. Kempegowda Institute Of Medical Sciences; IndiaFil: Grassi Almeida, Samanta Cristine. Adolfo Lutz Institute; BrasilFil: Ochoa, Theresa J.. Universidad Peruana Cayetano Heredia; PerúFil: Ho, Pak Leung. The University Of Hong Kong; Hong KongFil: du Plessis, Mignon. National Institute for Communicable Diseases; SudáfricaFil: Ndlangisa, Kedibone M.. National Institute for Communicable Diseases; SudáfricaFil: Cornick, Jennifer. Malawi liverpool wellcome Trust Clinical Research Programme; MalauiFil: Kwambana Adams, Brenda. Colegio Universitario de Londres; Reino Unido. Medical Research Council Unit The Gambia at The London School of Hygiene & Tropical Medicine; GambiaFil: Benisty, Rachel. Ben Gurion University of the Negev; IsraelFil: Nzenze, Susan A.. University of the Witwatersrand; SudáfricaFil: Madhi, Shabir A.. University of the Witwatersrand; SudáfricaFil: Hawkins, Paulina A.. Emory University; Estados UnidosFil: Faccone, Diego Francisco. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Área de Antimicrobianos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

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 theircombined 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 thesafety 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 atdelivery (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 clinicalmalaria during pregnancy, and reductions in the prevalence of peripheral parasitaemia (7.10% vs 15.15%) (p,0.001), and ofactively infected placentas (7.04% vs 13.60%) (p = 0.002). There was a reduction in severe anaemia at delivery of borderlinestatistical significance (p = 0.055). These effects were not modified by gravidity or HIV status. Reported ITN's use was morethan 90% in both groups.Conclusions:Two-dose SP was associated with a reduction in some indicators, but these were not translated to significantimprovement in other maternal or birth outcomes. The use of ITNs during pregnancy may reduce the need to administerIPTp. ITNs should be part of the ANC package in sub-Saharan Afric

Pneumococcal lineages associated with serotype replacement and antibiotic resistance in childhood invasive pneumococcal disease in the post-PCV13 era: an international whole-genome sequencing study

Background: Invasive pneumococcal disease remains an important health priority owing to increasing disease incidence caused by pneumococci expressing non-vaccine serotypes. We previously defined 621 Global Pneumococcal Sequence Clusters (GPSCs) by analysing 20 027 pneumococcal isolates collected worldwide and from previously published genomic data. In this study, we aimed to investigate the pneumococcal lineages behind the predominant serotypes, the mechanism of serotype replacement in disease, as well as the major pneumococcal lineages contributing to invasive pneumococcal disease in the post-vaccine era and their antibiotic resistant traits. Methods: We whole-genome sequenced 3233 invasive pneumococcal disease isolates from laboratory-based surveillance programmes in Hong Kong (n=78), Israel (n=701), Malawi (n=226), South Africa (n=1351), The Gambia (n=203), and the USA (n=674). The genomes represented pneumococci from before and after pneumococcal conjugate vaccine (PCV) introductions and were from children younger than 3 years. We identified predominant serotypes by prevalence and their major contributing lineages in each country, and assessed any serotype replacement by comparing the incidence rate between the pre-PCV and PCV periods for Israel, South Africa, and the USA. We defined the status of a lineage as vaccine-type GPSC (≥50% 13-valent PCV [PCV13] serotypes) or non-vaccine-type GPSC (>50% non-PCV13 serotypes) on the basis of its initial serotype composition detected in the earliest vaccine period to measure their individual contribution toward serotype replacement in each country. Major pneumococcal lineages in the PCV period were identified by pooled incidence rate using a random effects model. Findings: The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. The five most prevalent serotypes in the PCV13 period varied between countries, with only serotypes 5, 12F, 15B/C, 19A, 33F, and 35B/D common to two or more countries. These serotypes were associated with more than one lineage, except for serotype 5 (GPSC8). Serotype replacement was mainly mediated by expansion of non-vaccine serotypes within vaccine-type GPSCs and, to a lesser extent, by increases in non-vaccine-type GPSCs. A globally spreading lineage, GPSC3, expressing invasive serotypes 8 in South Africa and 33F in the USA and Israel, was the most common lineage causing non-vaccine serotype invasive pneumococcal disease in the PCV13 period. We observed that same prevalent non-vaccine serotypes could be associated with distinctive lineages in different countries, which exhibited dissimilar antibiotic resistance profiles. In non-vaccine serotype isolates, we detected significant increases in the prevalence of resistance to penicillin (52 [21%] of 249 vs 169 [29%] of 575, p=0·0016) and erythromycin (three [1%] of 249 vs 65 [11%] of 575, p=0·0031) in the PCV13 period compared with the pre-PCV period. Interpretation: Globally spreading lineages expressing invasive serotypes have an important role in serotype replacement, and emerging non-vaccine serotypes associated with different pneumococcal lineages in different countries might be explained by local antibiotic-selective pressures. Continued genomic surveillance of the dynamics of the pneumococcal population with increased geographical representation in the post-vaccine period will generate further knowledge for optimising future vaccine design. Funding: Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control.Fil: Lo, Stephanie W.. Wellcome Sanger Institute; Reino UnidoFil: Gladstone, Rebecca A.. Wellcome Sanger Institute; Reino UnidoFil: van Tonder, Andries J.. Wellcome Sanger Institute; Reino UnidoFil: Lees, John A.. University Of New York. School Of Medicine; Estados UnidosFil: du Plessis, Mignon. National Institute For Communicable Diseases; SudáfricaFil: Benisty, Rachel. Ben Gurion University of the Negev; IsraelFil: Givon Lavi, Noga. Ben Gurion University of the Negev; IsraelFil: Hawkins, Paulina A.. University of Emory. Rollins School of Public Health; Estados UnidosFil: Cornick, Jennifer E.. Malawi liverpool wellcome trust; MalauiFil: Kwambana Adams, Brenda. University College London; Estados UnidosFil: Law, Pierra Y.. University of Hong Kong; ChinaFil: Ho, Pak Leung. University of Hong Kong; ChinaFil: Antonio, Martin. Medical Research Council Unit The Gambia; GambiaFil: Everett, Dean B.. University of Edinburgh; Reino UnidoFil: Dagan, Ron. Ben Gurion University of the Negev; IsraelFil: Von Gottberg, Anne. National Institute For Communicable Diseases; SudáfricaFil: Klugman, Keith P.. University of Emory. Rollins School of Public Health; Estados UnidosFil: McGee, Lesley. Centers for Disease Control and Prevention; Estados UnidosFil: Breiman, Robert F.. University of Emory. Rollins School of Public Health; Estados UnidosFil: Bentley, Stephen D.. Wellcome Sanger Institute; Reino UnidoFil: Brooks, Abdullah W.. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Corso, Alejandra. The Global Pneumococcal Sequencing Consortium; Reino Unido. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Área de Antimicrobianos; ArgentinaFil: Davydov, Alexander. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Maguire, Alison. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Pollard, Andrew. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Kiran, Anmol. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Skoczynska, Anna. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Moiane, Benild. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Beall, Bernard. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Sigauque, Betuel. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Aanensen, David. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Lehmann, Deborah. The Global Pneumococcal Sequencing Consortium; Reino UnidoFil: Faccone, Diego Francisco. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Área de Antimicrobianos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

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$(CI 95$ (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

Epidemiology, Molecular Characterization and Antibiotic Resistance of Neisseria meningitidis from Patients ≤15 Years in Manhiça, Rural Mozambique

BACKGROUND: The epidemiology of meningococcal disease in Mozambique and other African countries located outside the "meningitis belt" remains widely unknown. With the event of upcoming vaccines microbiological and epidemiological information is urgently needed. METHODS: Prospective surveillance for invasive bacterial infections was conducted at the Manhiça District hospital (rural Mozambique) among hospitalized children below 15 years of age. Available Neisseria meningitidis isolates were serogrouped and characterized by Multilocus Sequence Typing (MLST). Antibiotic resistance was also determined. RESULTS: Between 1998 and 2008, sixty-three cases of confirmed meningococcal disease (36 meningitis, 26 sepsis and 1 conjunctivitis) were identified among hospitalized children. The average incidence rate of meningococcal disease was 11.6/100,000 (8/100,000 for meningitis and 3.7/100,000 for meningococcemia, respectively). There was a significant rise on the number of meningococcal disease cases in 2005-2006 that was sustained till the end of the surveillance period. Serogroup was determined for 43 of the 63 meningococcal disease cases: 38 serogroup W-135, 3 serogroup A and 2 serogroup Y. ST-11 was the most predominant sequence type and strongly associated with serogroup W-135. Two of the three serogroup A isolates were ST-1, and both serogroup Y isolates were ST-175. N. meningitidis remained highly susceptible to all antibiotics used for treatment in the country, although the presence of isolates presenting intermediate resistance to penicillin advocates for continued surveillance. CONCLUSIONS: Our data show a high rate of meningococcal disease in Manhiça, Mozambique, mainly caused by serogroup W-135 ST-11 strains, and advocates for the implementation of a vaccination strategy covering serogroup W-135 meningococci in the country

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.Peer reviewe