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1.
Antimicrob Resist Infect Control ; 10(1): 37, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597029

RESUMO

BACKGROUND: According to WHO ( CISMAC. Centre for Intervention Science in Maternal and Child health), the antimicrobial resistant bacteria considered to be clinically most important for human health and earmarked for surveillance include extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, carbapenem-resistant bacteria, methicillin-resistant (MRSA) and, macrolide-lincosamide-streptogramin B -resistant vancomycin-resistant (VRSA) Staphylococcus aureus and vancomycin-resistant Enterococcus (VRE). If these bacteria are carried in the female genital tract, they may be transmitted to the neonate causing local or systemic neonatal infections that can be difficult to treat with conventionally available antimicrobials. In order to develop effective treatment strategies, there is need for updated information about the prevalence of colonization with important antimicrobial-resistant pathogens. OBJECTIVE: We sought to estimate the prevalence of vaginal colonization with potentially pathogenic and clinically important AMR bacteria among women in labour in Uganda and to identify factors associated with colonization. METHODS: We conducted a cross-sectional study among HIV-1 and HIV-2 negative women in labour at three primary health care facilities in Uganda. Drug susceptibility testing was done using the disk diffusion method on bacterial isolates cultured from vaginal swabs. We calculated the prevalence of colonization with potentially pathogenic and clinically important AMR bacteria, in addition to multidrug-resistant (MDR) bacteria, defined as bacteria resistant to antibiotics from ≥ 3 antibiotic classes. RESULTS: We found that 57 of the 1472 enrolled women (3.9% prevalence; 95% Confidence interval [CI] 3.0%, 5.1%) were colonized with ESBL-producing Enterobacteriaceace, 27 (1.8%; 95% CI 1.2%, 2.6%) were colonized with carbapenem-resistant Enterobacteriaceae, and 85 (5.8%; 95% CI 4.6%, 7.1%) were colonized with MRSA. The prevalence of colonization with MDR bacteria was high (750/1472; 50.9%; 95% CI 48.4%, 53.5%). Women who were ≥ 30 years of age had higher odds of being colonized with MDR bacteria compared to women aged 20-24 years (OR 1.6; 95% CI 1.1, 2.2). CONCLUSION: Most of the women included in our study were vaginally colonized with potentially pathogenic MDR and other clinically important AMR bacteria. The high prevalence of colonization with these bacteria is likely to further increase the incidence of difficult-to-treat neonatal sepsis.

2.
Ann Glob Health ; 86(1): 132, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33102152

RESUMO

There remain a number of uncertainties globally about the risks posed to women who are infected with SARS-CoV-2 during pregnancy. Furthermore, our understanding of the spread of COVID-19 in Sub-Saharan Africa is limited, owing to low testing rates in many parts of the continent. PeriCOVID Africa, in conjunction with the WHO/HRP Alliance, plans to address these knowledge gaps by harnessing research infrastructures in place in five sub-Saharan African countries in order to screen more than 50,000 pregnant women and their infants for SARS-CoV-2, while monitoring pregnancy and neonatal outcomes. We anticipate that the results of this study will provide much needed information about the risks that SARS-CoV-2 poses to pregnant women and their babies, as well as establishing potential routes of mother-to-child transmission.


Assuntos
Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Pandemias , Pneumonia Viral , Complicações Infecciosas na Gravidez , Medição de Risco/métodos , África ao Sul do Saara/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Feminino , Humanos , Saúde do Lactente , Recém-Nascido , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Projetos de Pesquisa , Fatores de Risco , Saúde da Mulher
3.
Clin Infect Dis ; 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32857836

RESUMO

WHO convened an Advisory Group (AG) to consider the feasibility, potential value and limitations of establishing a closely-monitored challenge model of experimental SARS-CoV-2 infection and COVID-19 in healthy adult volunteers. The AG included experts in design, establishment and performance of challenges. This report summarizes issues that render a COVID-19 model daunting to establish (SARS-CoV-2's potential to cause severe/fatal illness, its high transmissibility, and lack of a "rescue treatment" to prevent progression from mild/moderate to severe clinical illness) and it proffers prudent strategies for stepwise model development, challenge virus selection, guidelines for manufacturing challenge doses, and ways to contain SARS-CoV-2 and prevent transmission to household/community contacts. A COVID-19 model could demonstrate protection against virus shedding and/or illness induced by prior SARS-CoV-2 challenge or vaccination. A limitation of the model is that vaccine efficacy in experimentally challenged healthy young adults cannot per se be extrapolated to predict efficacy in elderly/high-risk adults.

4.
PLoS One ; 15(8): e0237085, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776958

RESUMO

BACKGROUND: Sepsis is the third most common cause of death among neonates, with about 225,000 newborns dying every year globally. Data concerning the microbial etiology of neonatal sepsis and antimicrobial resistance profiles of its causative agents are necessary to inform targeted and effective treatment and prevention strategies. OBJECTIVE: To determine the proportion of newborns with symptoms and signs of sepsis who had a positive blood culture, its bacterial etiology, the antimicrobial resistance patterns as well as the factors associated with culture-positivity and case fatality at Mulago national referral hospital in Uganda. METHODS: We conducted a cross-sectional study among 359 neonates with symptoms and signs of sepsis who presented to the pediatric emergency care unit of Mulago national referral hospital from mid-January to end of December 2018. We performed blood culture and antimicrobial susceptibility testing, and conducted polymerase chain reaction to identify methicillin-resistant Staphylococcus aureus (MRSA) isolates. We used multivariable logistic regression to estimate the association between potential risk factors and culture-positive neonatal sepsis. FINDINGS: Of the 359 neonates recruited, 46 (12.8%; 95% CI 9.5%, 16.7%) had a positive blood culture. The predominant isolated bacteria were Staphylococcus aureus in 29 (63.0%), Escherichia coli in seven (15.2%), and Klebsiella pneumoniae in five (10.9%). Of the 46 pathogens, 73.9% were resistant to ampicillin, 23.9% to gentamicin and 8.7% to ceftriaxone. We isolated MRSA from the blood specimens of 19 (5.3%) of the 359 neonates, while 3 (0.8%) grew extended spectrum beta lactamase producers. The case fatality risk among neonates with neonatal sepsis was 9.5% (95% CI: 6.6%, 13.0%). Cesarean section delivery was strongly associated with culture-positive sepsis (adjusted odds ratio 3.45, 95% CI: 1.2, 10.1). CONCLUSION: One in eight neonates with clinical signs of sepsis grew a likely causative bacterial pathogen. S. aureus was the main pathogen isolated and a third of these isolates were MRSA. A significant proportion of the isolated bacterial pathogens were resistant to the first and second line antibiotics used for the treatment of neonatal sepsis. There is need to revisit the current treatment guidelines for neonatal sepsis.


Assuntos
Sepse Neonatal/epidemiologia , Infecções Estafilocócicas/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hospitais Pediátricos/estatística & dados numéricos , Humanos , Recém-Nascido , Masculino , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Sepse Neonatal/etiologia , Sepse Neonatal/microbiologia , Infecções Estafilocócicas/etiologia , Infecções Estafilocócicas/microbiologia , Uganda
5.
Epidemiology ; 31(5): 668-676, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32618713

RESUMO

BACKGROUND: Use of uterotonics like oxytocin to induce or augment labor has been shown to reduce placental perfusion and oxygen supply to the fetus, and studies indicate that it may increase the risk of stillbirth and neonatal asphyxia. Antenatal use of uterotonics, even without the required fetal monitoring and prompt access to cesarean section, is widespread, yet no study has adequately estimated the risk of intrapartum stillbirth and early neonatal deaths ascribed to such use. We conducted a case-control study to estimate this risk. METHODS: We conducted a population-based case-control study nested in a cluster-randomized trial. From 2008 to 2010, we followed pregnant women in rural Haryana, India, monthly until delivery. We visited all live-born infants on day 29 to ascertain whether they were alive. We conducted verbal autopsies for stillbirths and neonatal deaths. Cases (n = 2,076) were the intrapartum stillbirths and day-1 deaths (early deaths), and controls (n = 532) were live-born babies who died between day 8 and 28 (late deaths). RESULTS: Antenatal administration of uterotonics preceded 74% of early and 62% of late deaths, translating to an adjusted odds ratio (95% confidence interval [CI]) for early deaths of 1.7 (95% CI = 1.4, 2.1), and a population attributable risk of 31% (95% CI = 22%, 38%). CONCLUSIONS: Antenatal administration of uterotonics was associated with a substantially increased risk of intrapartum stillbirth and day-1 death. See video abstract: http://links.lww.com/EDE/B707.

6.
BMC Pediatr ; 20(1): 150, 2020 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-32247311

RESUMO

BACKGROUND: In a randomized controlled trial (RCT) with 8402 stable low birthweight (LBW) infants, majority being late preterm or term small for gestational age, community-initiated KMC (ciKMC) showed a significant improvement in survival. However, the effect of ciKMC on neurodevelopment is unclear. This is important to elucidate as children born with low birth weight are at high risk of neurodevelopmental deficits. In the first 552 stable LBW infants enrolled in the above trial, we evaluated the effect of ciKMC on neurodevelopmental outcomes during infancy. METHOD: This RCT was conducted among 552 stable LBW infants, majorly late preterm or term small for gestational age infants without any problems at birth and weighing 1500-2250 g at birth. The intervention comprised of promotion of skin-to-skin contact and exclusive breastfeeding by trained intervention delivery team through home visits. The intervention group mother-infant-dyads were supported to practice ciKMC till day 28 after birth or until the baby wriggled-out. All infants in the intervention and control groups received Home Based Post Natal Care (HBPNC) visits by government health workers. Cognitive, language, motor and socio-emotional outcomes were assessed at infant-ages 6- and 12-months using Bayley Scale of Infant Development (BSID-III). Other outcomes measured were infant temperament, maternal depression, maternal sense of competence, mother-infant bonding and home-environment. We performed post-hoc equivalence testing using two one-sided tests of equivalence (TOST) to provide evidence that ciKMC does not do harm in terms of neurodevelopment. RESULTS: In the intervention arm, the median (IQR) time to initiate ciKMC was 48 (48 to 72) hours after birth. The mean (SD) duration of skin-to-skin-contact was 27.9 (3.9) days with a mean (SD) of 8.7 (3.5) hours per day. We did not find significant effect of ciKMC on any of the child developmental outcomes during infancy. The TOST analysis demonstrated that composite scores for cognitive, language and motor domains at 12 months among the study arms were statistically equivalent. CONCLUSION: Our study was unable to capture any effect of ciKMC on neurodevelopment during infancy in this sample of stable late preterm or term small for gestational age infants. Long term follow-up may provide meaningful insights. TRIAL REGISTRATION: The trial is registered at clinicaltrials.gov NCT02631343 dated February 17, 2016; Retrospectively registered.

7.
BMC Infect Dis ; 20(1): 98, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005177

RESUMO

BACKGROUND: Potentially pathogenic bacteria that colonise the lower genital tract of women in labour can be passed to the baby during birth. While many babies become colonised with these bacteria after delivery, a few develop neonatal infections. The lower genital tract is a reservoir for potential pathogens and a source of infection for neonates. We determined the prevalence of vaginal colonisation of potentially pathogenic bacteria among women in labour in Central Uganda and identified potential risk factors associated with this colonisation. METHODS: We conducted a cross sectional study at three primary health care facilities and collected vaginal swabs from HIV-1 negative women in labour. Specimens were cultured on different selective microbiological media, and biochemical tests were used to classify bacterial isolates on the species level. Multivariable logistic regression analyses were used to estimate the association between relevant exposures and colonisation with potentially pathogenic bacteria. RESULTS: We recruited 1472 women in labour whose mean age was 24.6 years (standard deviation [SD] 4.9). Of these, 955 (64.9%; 95% Confidence Interval [CI] 62.4, 67%) were vaginally colonised with at least one potentially pathogenic bacterial species. The most commonly isolated species were Escherichia coli (n = 508; 34.5%), Klebsiella pneumoniae (n = 144; 9.8%) and Staphylococcus aureus (n = 121; 8.2%). Results from exploratory multivariable regression analyses indicated that having had ≥5 previous pregnancies (adjusted odds ratio [aOR] 0.59; 95% CI 0.35, 0.97) or being ≥30 years old (aOR 1.52; 95% CI 1.03, 2.23) could be associated with vaginal colonisation with any potentially pathogenic bacteria, as well as with vaginal colonisation with S. aureus (aOR 0.33; 95% CI 0.12, 0.88, and aOR 2.17; 95% CI 1.17, 4.00, respectively). Possession of domestic animals in a household (aOR 0.57; 95% CI 0.35, 0.92) could be associated with vaginal colonisation with E. coli. CONCLUSIONS: Two-thirds of HIV-1 negative women in labour were vaginally colonised by potentially pathogenic bacteria, mainly E. coli, K. pneumoniae, and S. aureus.


Assuntos
Infecções por Escherichia coli/epidemiologia , Infecções por Klebsiella/epidemiologia , Complicações Infecciosas na Gravidez/microbiologia , Infecções Estafilocócicas/epidemiologia , Vagina/microbiologia , Adulto , Estudos Transversais , Feminino , Soropositividade para HIV/epidemiologia , Humanos , Trabalho de Parto , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Prevalência , Atenção Primária à Saúde , Fatores de Risco , Uganda/epidemiologia , Adulto Jovem
8.
Lancet Glob Health ; 8(2): e204-e214, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31864916

RESUMO

BACKGROUND: The Global Enteric Multicenter Study (GEMS) was a 3-year case-control study that measured the burden, aetiology, and consequences of moderate-to-severe diarrhoea (MSD) in children aged 0-59 months. GEMS-1A, a 12-month follow-on study, comprised two parallel case-control studies, one assessing MSD and the other less-severe diarrhoea (LSD). In this report, we analyse the risk of death with each diarrhoea type and the specific pathogens associated with fatal outcomes. METHODS: GEMS was a prospective, age-stratified, matched case-control study done at seven sites in Africa and Asia. Children aged 0-59 months with MSD seeking care at sentinel health centres were recruited along with one to three randomly selected matched community control children without diarrhoea. In the 12-month GEMS-1A follow-on study, children with LSD and matched controls, in addition to children with MSD and matched controls, were recruited at six of the seven sites; only cases of MSD and controls were enrolled at the seventh site. We compared risk of death during the period between enrolment and one follow-up household visit done about 60 days later (range 50-90 days) in children with MSD and LSD and in their respective controls. Approximately 50 pathogens were detected using, as appropriate, classic bacteriology, immunoassays, gel-based PCR and reverse transcriptase PCR, and quantitative real-time PCR (qPCR). Specimens from a subset of GEMS cases and controls were also tested by a TaqMan Array Card that compartmentalised probe-based qPCR for 32 enteropathogens. FINDINGS: 223 (2·0%) of 11 108 children with MSD and 43 (0·3%) of 16 369 matched controls died between study enrolment and the follow-up visit at about 60 days (hazard ratio [HR] 8·16, 95% CI 5·69-11·68, p<0·0001). 12 (0·4%) of 2962 children with LSD and seven (0·2%) of 4074 matched controls died during the follow-up period (HR 2·78, 95% CI 0·95-8·11, p=0·061). Risk of death was lower in children with dysenteric MSD than in children with non-dysenteric MSD (HR 0·20, 95% CI 0·05-0·87, p=0·032), and lower in children with LSD than in those with non-dysenteric MSD (HR 0·29, 0·14-0·59, p=0·0006). In children younger than 24 months with MSD, infection with typical enteropathogenic Escherichia coli, enterotoxigenic E coli encoding heat-stable toxin, enteroaggregative E coli, Shigella spp (non-dysentery cases), Aeromonas spp, Cryptosporidium spp, and Entamoeba histolytica increased risk of death. Of 61 deaths in children aged 12-59 months with non-dysenteric MSD, 31 occurred among 942 children qPCR-positive for Shigella spp and 30 deaths occurred in 1384 qPCR-negative children (HR 2·2, 95% CI 1·2-3·9, p=0·0090), showing that Shigella was strongly associated with increased risk of death. INTERPRETATION: Risk of death is increased following MSD and, to a lesser extent, LSD. Considering there are approximately three times more cases of LSD than MSD in the population, more deaths are expected among children with LSD than in those with MSD. Because the major attributable LSD-associated and MSD-associated pathogens are the same, implementing vaccines and rapid diagnosis and treatment interventions against these major pathogens are rational investments. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Diarreia/epidemiologia , Diarreia/mortalidade , Carga Global da Doença/estatística & dados numéricos , Pobreza/estatística & dados numéricos , Estudos de Casos e Controles , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Mortalidade , Estudos Prospectivos
10.
Lancet ; 394(10210): 1724-1736, 2019 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-31590989

RESUMO

BACKGROUND: Coverage of kangaroo mother care remains very low despite WHO recommendations for its use for babies with low birthweight in health facilities for over a decade. Initiating kangaroo mother care at the community level is a promising strategy to increase coverage. However, knowledge of the efficacy of community-initiated kangaroo mother care is still lacking. We aimed to assess the effect of community-initiated kangaroo mother care provided to babies weighing 1500-2250 g on neonatal and infant survival. METHODS: In this randomised controlled, superiority trial, undertaken in Haryana, India, we enrolled babies weighing 1500-2250 g at home within 72 h of birth, if not already initiated in kangaroo mother care, irrespective of place of birth (ie, home or health facility) and who were stable and feeding. The first eligible infants in households were randomly assigned (1:1) to the intervention (community-initiated kangaroo mother care) or control group by block randomisation using permuted blocks of variable size. Twins were allocated to the same group. For second eligible infants in the same household as an enrolled infant, if the first infant was assigned to the intervention group the second infant was also assigned to this group, whereas if the first infant was assigned to the control group the second infant was randomly assigned (1:1) to the intervention or control group. Mothers and infants in the intervention group were visited at home (days 1-3, 5, 7, 10, 14, 21, and 28) to support kangaroo mother care (ie, skin-to-skin contact and exclusive breastfeeding). The control group received routine care. The two primary outcomes were mortality between enrolment and 28 days and between enrolment and 180 days. Analysis was by intention to treat and adjusted for clustering within households. The effect of the intervention on mortality was assessed with person-time in the denominator using Cox proportional hazards model. This study is registered with ClinicalTrials.gov, NCT02653534 and NCT02631343, and is now closed to new participants. FINDINGS: Between July 30, 2015, and Oct 31, 2018, 8402 babies were enrolled, of whom 4480 were assigned to the intervention group and 3922 to the control group. Most births (6837 [81·4%]) occurred at a health facility, 36·2% (n=3045) had initiated breastfeeding within 1 h of birth, and infants were enrolled at an average of about 30 h (SD 17) of age. Vital status was known for 4470 infants in the intervention group and 3914 in the control group at age 28 days, and for 3653 in the intervention group and 3331 in the control group at age 180 days. Between enrolment and 28 days, 73 infants died in 4423 periods of 28 days in the intervention group and 90 deaths in 3859 periods of 28 days in the control group (hazard ratio [HR] 0·70, 95% CI 0·51-0·96; p=0·027). Between enrolment and 180 days, 158 infants died in 3965 periods of 180 days in the intervention group and 184 infants died in 3514 periods of 180 days in the control group (HR 0·75, 0·60-0·93; p=0·010). The risk ratios for death were almost the same as the HRs (28-day mortality 0·71, 95% CI 0·52- 0·97; p=0·032; 180-day mortality 0·76, 0·60-0·95; p=0·017). INTERPRETATION: Community-initiated kangaroo mother care substantially improves newborn baby and infant survival. In low-income and middle-income countries, incorporation of kangaroo mother care for all infants with low birthweight, irrespective of place of birth, could substantially reduce neonatal and infant mortality. FUNDING: Research Council of Norway and University of Bergen.


Assuntos
Mortalidade Infantil , Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Método Canguru/métodos , Mortalidade Perinatal , Desenvolvimento Infantil , Serviços de Saúde Comunitária , Feminino , Humanos , Índia , Lactente , Recém-Nascido , Método Canguru/estatística & dados numéricos , Masculino , Projetos de Pesquisa , Fatores Socioeconômicos , Resultado do Tratamento
11.
Trop Med Int Health ; 24(9): 1088-1097, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31325406

RESUMO

OBJECTIVES: To assess the prevalence of prolonged and persistent diarrhoea, to estimate their co-occurrence with acute malnutrition and association with demographic and clinical factors. METHODS: Case-control study where cases were children under 5 years of age with diarrhoea and controls were children without diarrhoea, frequency-matched weekly by age and district of residency. Controls for cases 0-11 months were recruited from vaccination rooms, and controls for cases 12-59 months were recruited by house visits using random locations in the catchment area of the study sites. Data were analysed by mixed model logistic regression. RESULTS: We enrolled 1134 cases and 946 controls. Among the cases, 967 (85%) had acute diarrhoea (AD), 129 (11%) had ProD and 36 (3.2%) had PD. More cases had acute malnutrition at enrolment (17% vs. 4%, P < 0.0001) and more were born prematurely (5.7% vs. 1.8%, P < 0.0001) than controls. About 75% of ProPD cases did not have acute malnutrition. Cases with AD and ProPD had different symptomatology, even beyond illness duration. CONCLUSIONS: ProPD is common among children presenting with diarrhoea and is not confined to children with acute malnutrition. There is an urgent need for studies assessing causes of ProPD with and without acute malnutrition to develop treatment guidelines for these conditions.


Assuntos
Diarreia/epidemiologia , Desnutrição/epidemiologia , Doença Aguda , Fatores Etários , Estudos de Casos e Controles , Transtornos da Nutrição Infantil/epidemiologia , Pré-Escolar , Doença Crônica , Diarreia/fisiopatologia , Diarreia/terapia , Etiópia , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Desnutrição/fisiopatologia , Desnutrição/terapia , Prevalência , Fatores de Risco , Fatores Sexuais , Fatores Socioeconômicos
12.
Pathogens ; 8(2)2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31234485

RESUMO

Infection with enterotoxigenic Escherichia coli (ETEC) producing the heat-stable enterotoxin (ST) is one of the most important causes of childhood diarrhoea in low- and middle-income countries. Here, we undertook a controlled human infection model (CHIM) study to investigate whether ST-producing ETEC strain TW11681 would be suitable for testing the protective efficacy of new ST-based vaccine candidates in vaccine challenge models. In groups of three, nine volunteers ingested 1 × 106, 1 × 107, or 1 × 108 colony-forming units (CFU) of TW11681. Flow cytometry-based assays were used to measure CD4+ T cell responses and antibody levels targeting virulence factors expressed by the strain. We found that infection with TW11681 elicited few and mild symptoms, including mild diarrhoea in two volunteers, both of whom ingested 1 × 106 CFU. Averaged across all volunteers, the CD4+ T cell responses specific for E. coli YghJ mucinase peaked 10 days after infection (3.2-fold (p = 0.016)), while the CD4+ T cell responses specific for Colonization Factor Antigen I (CFA/I) major fimbrial subunit (CfaB) peaked after 28 days (3.6-fold (p = 0.063)). The serum CfaB-specific anti-IgA and anti-IgG/IgM levels were significantly increased and peaked 3 months after infection. Both remained elevated for the duration of the 12-month follow-up. The corresponding anti-YghJ serological response was strongest after 10 days, although a significant increase was seen only for IgA levels (3.2-fold (p = 0.008)). In conclusion, due to its low diarrhoea attack risk, TW11681 is probably not suitable for testing the efficacy of new vaccines in human challenge studies at doses 1 × 106 to 1 × 108. However, the strain may still be useful in CHIMs for studying ETEC host-pathogen interactions.

13.
Infect Immun ; 87(7)2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31061144

RESUMO

Infection with enterotoxigenic Escherichia coli (ETEC) is a common cause of childhood diarrhea in low- and middle-income countries, as well as of diarrhea among travelers to these countries. In children, ETEC strains secreting the heat-stable toxin (ST) are the most pathogenic, and there are ongoing efforts to develop vaccines that target ST. One important challenge for ST vaccine development is to construct immunogens that do not elicit antibodies that cross-react with guanylin and uroguanylin, which are endogenous peptides involved in regulating the activity of the guanylate cyclase-C (GC-C) receptor. We immunized mice with both human ST (STh) and porcine ST (STp) chemically coupled to bovine serum albumin, and the resulting sera neutralized the toxic activities of both STh and STp. This suggests that a vaccine based on either ST variant can confer cross-protection. However, several anti-STh and anti-STp sera cross-reacted with the endogenous peptides, suggesting that the ST sequence must be altered to reduce the risk of unwanted cross-reactivity. Epitope mapping of four monoclonal anti-STh and six anti-STp antibodies, all of which neutralized both STh and STp, revealed that most epitopes appear to have at least one amino acid residue shared with guanylin or uroguanylin. Despite this, only one monoclonal antibody displayed demonstrable cross-reactivity to the endogenous peptides, suggesting that targeted mutations of a limited number of ST residues may be sufficient to obtain a safe ST-based vaccine.


Assuntos
Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/imunologia , Toxinas Bacterianas/imunologia , Escherichia coli Enterotoxigênica/imunologia , Enterotoxinas/imunologia , Infecções por Escherichia coli/imunologia , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/imunologia , Hormônios Gastrointestinais/imunologia , Peptídeos Natriuréticos/imunologia , Animais , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Reações Cruzadas , Escherichia coli Enterotoxigênica/genética , Enterotoxinas/administração & dosagem , Enterotoxinas/química , Enterotoxinas/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Proteínas de Escherichia coli/administração & dosagem , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/genética , Humanos , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Suínos
14.
Lancet Glob Health ; 7(5): e568-e584, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31000128

RESUMO

BACKGROUND: Diarrheal diseases remain a leading cause of illness and death among children younger than 5 years in low-income and middle-income countries. The Global Enteric Multicenter Study (GEMS) has described the incidence, aetiology, and sequelae of medically attended moderate-to-severe diarrhoea (MSD) among children aged 0-59 months residing in censused populations in sub-Saharan Africa and south Asia, where most child deaths occur. To further characterise this disease burden and guide interventions, we extended this study to include children with episodes of less-severe diarrhoea (LSD) seeking care at health centres serving six GEMS sites. METHODS: We report a 1-year, multisite, age-stratified, matched case-control study following on to the GEMS study. Six sites (Bamako, Mali; Manhiça, Mozambique; Basse, The Gambia; Mirzapur, Bangladesh; Kolkata, India; and Bin Qasim Town, Karachi, Pakistan) participated in this study. Children aged 0-59 months at each site who sought care at a sentinel hospital or health centre during a 12-month period were screened for diarrhoea. New (onset after ≥7 diarrhoea-free days) and acute (onset within the previous 7 days) episodes of diarrhoea in children who had sunken eyes, whose skin lost turgor, who received intravenous hydration, who had dysentery, or who were hospitalised were eligible for inclusion as MSD. The remaining new and acute diarrhoea episodes among children who sought care at the same health centres were considered LSD. We aimed to enrol the first eight or nine eligible children with MSD and LSD at each site during each fortnight in three age strata: infants (aged 0-11 months), toddlers (aged 12-23 months), and young children (aged 24-59 months). For each included case of MSD or LSD, we enrolled one to three community control children without diarrhoea during the previous 7 days. From patients and controls we collected clinical and epidemiological data, anthropometric measurements, and faecal samples to identify enteropathogens at enrolment, and we performed a follow-up home visit about 60 days later to ascertain vital status, clinical outcome, and interval growth. Primary outcomes were to characterise, for MSD and LSD, the pathogen-specific attributable risk and population-based incidence values, and to assess the frequency of adverse clinical consequences associated with these two diarrhoeal syndromes. FINDINGS: From Oct 31, 2011, to Nov 14, 2012, we recruited 2368 children with MSD, 3174 with LSD, and one to three randomly selected community control children without diarrhoea matched to cases with MSD (n=3597) or LSD (n=4236). Weighted adjusted population attributable fractions showed that most attributable cases of MSD and LSD were due to rotavirus, Cryptosporidium spp, enterotoxigenic Escherichia coli encoding heat-stable toxin (with or without genes encoding heat-labile enterotoxin), and Shigella spp. The attributable incidence per 100 child-years for LSD versus MSD, by age stratum, for rotavirus was 22·3 versus 5·5 (0-11 months), 9·8 versus 2·9 (12-23 months), and 0·5 versus 0·2 (24-59 months); for Cryptosporidium spp was 3·6 versus 2·3 (0-11 months), 4·3 versus 0·6 (12-23 months), and 0·3 versus 0·1 (24-59 months); for enterotoxigenic E coli encoding heat-stable toxin was 4·2 versus 0·1 (0-11 months), 5·2 versus 0·0 (12-23 months), and 1·1 versus 0·2 (24-59 months); and for Shigella spp was 1·0 versus 1·3 (0-11 months), 3·1 versus 2·4 (12-23 months), and 0·8 versus 0·7 (24-59 months). Participants with both MSD and LSD had significantly more linear growth faltering than controls at follow-up. INTERPRETATION: Inclusion of participants with LSD markedly expands the population of children who experience adverse clinical and nutritional outcomes from acute diarrhoeal diseases. Since MSD and LSD have similar aetiologies, interventions targeting rotavirus, Shigella spp, enterotoxigenic E coli producing heat-stable toxin, and Cryptosporidium spp might substantially reduce the diarrhoeal disease burden and its associated nutritional faltering. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Diarreia Infantil/epidemiologia , Diarreia/epidemiologia , Fatores Etários , Estudos de Casos e Controles , Pré-Escolar , Diarreia/complicações , Diarreia/etiologia , Diarreia Infantil/complicações , Diarreia Infantil/etiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino
15.
PLoS One ; 14(2): e0211411, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30730915

RESUMO

BACKGROUND: Despite the fact that Uganda has been a signatory to the global strategy for Infant and Young Children Feeding practices (IYCF) for nearly a decade, the prevalence of stunting among children under five years of age remains tragically high at 17% in Eastern Uganda and twofold higher countrywide. Only 6% of all children aged 6-23 months feed adequately. This study aimed to establish the covariates of complementary feeding (CF) and its effect on attained height among primary school-aged children in Mbale district (Eastern Uganda). METHODS: This was a community-based prospective cohort study using data from the PROMISE EBF trial. The main exposure variable was adequate complementary feeding (CF) measured in a parent questionnaire at 18-24 months of age. We defined adequate CF as having received animal food, cereals and fruit, juice and/or vegetables during the 24 hours preceding the interview. An adapted minimum acceptable diet was defined as having been given milk or milk products at least twice a day, an adapted meal frequency of two and solid or semi-solid food from at least four food groups on a 24-hour dietary recall based on modified IYCF criteria. The main outcome variable was attained height [(height-for-age Z score (HAZ)] measured between five and eight years of age using the WHO growth standards. Effects of CF on HAZ were estimated using linear regression analyses with cluster-robust standard errors. RESULTS: A total of 506 children were studied. The majority (85%) were from rural areas and the average age at the end of the study was 6.9 (standard deviation: 0.63) years. Of these, 23.9% were adequately fed and 2.3% received the adapted minimum acceptable diet. Adequate CF was not associated with HAZ (adjusted ß = -0.111; 95% CI: -0.363, 0.141; p = 0.374). Factors significantly associated with attained height were baseline HAZ (0.262; 0.152, 0.374; p<0.001) and WHZ (-0.147; -0.243, -0.051; p = 0.004), child's age (0.454; -0.592, -0.315; p<0.001) and maternal education (0.030; 95% CI: 0.003, 0.057; p = 0.034). CONCLUSION: Adequate CF at age 18-24 months was worryingly insufficient and not associated with attained HAZ at age 5-8 years. Further strategies need to be considered to improve child nutrition and linear growth in resource-constrained settings.


Assuntos
Estatura/fisiologia , Fenômenos Fisiológicos da Nutrição do Lactente , Instituições Acadêmicas/estatística & dados numéricos , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Lactente , Masculino , Estado Nutricional , Estudos Prospectivos , Uganda
16.
PLoS Negl Trop Dis ; 13(1): e0007037, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30608930

RESUMO

BACKGROUND: Enterotoxigenic Escherichia coli (ETEC) encoding heat-stable enterotoxin (ST) alone or with heat-labile enterotoxin (LT) cause moderate-to-severe diarrhea (MSD) in developing country children. The Global Enteric Multicenter Study (GEMS) identified ETEC encoding ST among the top four enteropathogens. Since the GEMS objective was to provide evidence to guide development and implementation of enteric vaccines and other interventions to diminish diarrheal disease morbidity and mortality, we examined colonization factor (CF) prevalence among ETEC isolates from children age <5 years with MSD and from matched controls in four African and three Asian sites. We also assessed strength of association of specific CFs with MSD. METHODOLOGY/PRINCIPAL FINDINGS: MSD cases enrolled at healthcare facilities over three years and matched controls were tested in a standardized manner for many enteropathogens. To identify ETEC, three E. coli colonies per child were tested by polymerase chain reaction (PCR) to detect genes encoding LT, ST; confirmed ETEC were examined by PCR for major CFs (Colonization Factor Antigen I [CFA/I] or Coli Surface [CS] antigens CS1-CS6) and minor CFs (CS7, CS12, CS13, CS14, CS17, CS18, CS19, CS20, CS21, CS30). ETEC from 806 cases had a single toxin/CF profile in three tested strains per child. Major CFs, components of multiple ETEC vaccine candidates, were detected in 66.0% of LT/ST and ST-only cases and were associated with MSD versus matched controls by conditional logistic regression (p≤0.006); major CFs detected in only 25.0% of LT-only cases weren't associated with MSD. ETEC encoding exclusively CS14, identified among 19.9% of 291 ST-only and 1.5% of 259 LT/ST strains, were associated with MSD (p = 0.0011). No other minor CF exhibited prevalence ≥5% and significant association with MSD. CONCLUSIONS/SIGNIFICANCE: Major CF-based efficacious ETEC vaccines could potentially prevent up to 66% of pediatric MSD cases due to ST-encoding ETEC in developing countries; adding CS14 extends coverage to ~77%.


Assuntos
Escherichia coli Enterotoxigênica/genética , Escherichia coli Enterotoxigênica/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Fímbrias/genética , Fatores de Virulência/genética , África/epidemiologia , Ásia/epidemiologia , Estudos de Casos e Controles , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase , Prevalência
17.
Hum Vaccin Immunother ; 15(6): 1379-1388, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30081709

RESUMO

Infection with enterotoxigenic Escherichia coli (ETEC) is an important cause of diarrhea-related illness and death among children under 5 years of age in low- and middle-income countries (LMIC). Recent studies have found that it is the ETEC subtypes that produce the heat-stable enterotoxin (ST), irrespective of whether they also secrete the heat-labile enterotoxin (LT), which contribute most importantly to the disease burden in children from LMIC. Therefore, adding an ST toxoid would importantly complement ongoing ETEC vaccine development efforts. The ST's potent toxicity, its structural similarity to the endogenous peptides guanylin and uroguanylin, and its poor immunogenicity have all complicated the advancement of ST-based vaccine development. Recent remarkable progress, however, including the unprecedented screening for optimal ST mutants, mapping of cross-reacting ST epitopes and improved ST-carrier coupling strategies (bioconjugation and genetic fusion), enables the rational design of safe, immunogenic, and well-defined ST-based vaccine candidates.


Assuntos
Toxinas Bacterianas/imunologia , Escherichia coli Enterotoxigênica/imunologia , Enterotoxinas/imunologia , Infecções por Escherichia coli/prevenção & controle , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/genética , Reações Cruzadas , Escherichia coli Enterotoxigênica/genética , Enterotoxinas/administração & dosagem , Enterotoxinas/genética , Proteínas de Escherichia coli/administração & dosagem , Proteínas de Escherichia coli/genética , Humanos , Camundongos
18.
BMC Pregnancy Childbirth ; 18(1): 476, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30514237

RESUMO

BACKGROUND: Cleansing the umbilical cord with chlorhexidine reduces neonatal morbidity and mortality, particularly in communities where newborn deaths and home births are common. As a result, the World Health Organization and national authorities are advocating the scale up of this intervention. In order for such a scale up to be effective, it has to be acceptable to the targeted population. With the overall aim to clarify conditions for scale-up, this study explored the acceptability of single dose chlorhexidine solution for umbilical cord care among health workers and infant care providers in the districts of Kampala and Mukono in Central Uganda. METHODS: This was a qualitative study that involved mothers of neonates enrolled in a chlorhexidine trial, nurses implementing the trial, key community members and opinion leaders in childcare. We conducted 30 in depth interviews (IDIs) with mothers (18), health workers (8), traditional birth attendants (2), a father (1) and a grandmother (1) and 4 focus group discussions (FGDs), 3 with mothers and 1 with health workers. We used qualitative content analysis to analyze our findings and borrow upon Sekhon's model when presenting our findings. RESULTS: Cognitive and emotional responses to chlorhexidine use included ease of use, and a perception that chlorhexidine reduced smell and abdominal colic. We also found that wider social and cultural factors were important to chlorhexidine use. These included cultural value put on quick separation of the umbilical cord as well as the practice of bathing the baby in a herbal mixture called kyogero. We also found that older relatives were key decision makers in umbilical cord care for newborns, but were seldom present during health workers' counseling of mothers about hygienic care of the cord. CONCLUSIONS: The application of chlorhexidine on the umbilical cord stump at birth was acceptable as an addition rather than a total replacement of traditional substances. The scale up of chlorhexidine should consider how to accommodate local beliefs and practices in a way that does not compromise the effect of the intervention; encouraging mothers to delay the bathing of babies in kyogero could be one way of doing this.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Clorexidina/uso terapêutico , Doenças do Recém-Nascido/prevenção & controle , Mães , Aceitação pelo Paciente de Cuidados de Saúde , Assistência Perinatal/métodos , Cordão Umbilical , Adulto , Agentes Comunitários de Saúde , Feminino , Grupos Focais , Humanos , Ciência da Implementação , Recém-Nascido , Infecções , Tocologia , Enfermeiras e Enfermeiros , Pesquisa Qualitativa , Autoeficácia , Uganda
19.
Gut Pathog ; 10: 46, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30349586

RESUMO

Background: As part of the effort to develop an enterotoxigenic Escherichia coli (ETEC) human challenge model for testing new heat-stable toxin (ST)-based vaccine candidates, a controlled human infection model study based on the ST-producing ETEC strain TW11681 was undertaken. Here, we estimate stool TW11681 DNA concentration and evaluate its association with dose, clinical symptoms, and with levels of antibodies targeting the CfaB subunit of the ETEC Colonization Factor Antigen I and the E. coli mucinase YghJ. Nine volunteers ingested different doses of the strain and were subsequently followed for 9 days with daily stool specimen collection and clinical examination. Stool DNA was purified by using a newly developed microplate-based method, and DNA originating from TW11681 was quantified by using a probe-based quantitative PCR assay. Antibody levels against CfaB and YghJ were measured in serum collected before and 10 and 28 days after TW11681 was ingested by using a bead-based flow cytometry immunoassay. Results: For 6 of the 9 volunteers, the stool TW11681 DNA concentration increased sharply a median 3.5 (range 2-5) days after dose ingestion, peaking at a median of 5.4% (range 3.3-8.2%) of the total DNA in the specimen. The concentration then fell sharply during the subsequent days, sometimes even before the onset of antibiotic treatment. The size or timing of these proliferation peaks did not seem to be associated with the number of TW11681 bacteria ingested, but the 2 volunteers who developed diarrhea and all five who experienced abdominal pains or cramps had these peaks. The 3 volunteers who did not have the proliferation peaks experienced fewer symptoms and they generally had relatively low CfaB- and YghJ-specific antibody levels before ingesting the strain and subsequently weaker responses than the other volunteers afterwards. Conclusions: Since the lack of proliferation peaks appears to be associated with fewer clinical symptoms and lower serum antibody responses to virulence factors of the infecting strain, it may be important to account for proliferation peaks when explaining results from controlled human infection model studies and for improving the accuracy of protective efficacy estimates when testing new ETEC diarrhea vaccine candidates.

20.
BMC Public Health ; 18(1): 307, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29499685

RESUMO

BACKGROUND: Low and middle income countries (LMICs), including India, contribute to a major proportion of low birth weight (LBW) infants globally. These infants require special care. Kangaroo Mother Care (KMC) in hospitals is a cost effective and efficacious intervention. In institutional deliveries, the duration of facility stay is often short. In LMICs, a substantial proportion of deliveries still occur at home and access to health care services is limited. In these circumstances, a pragmatic choice may be to initiate KMC at home for LBW babies. However, evidence is lacking on benefits of community-initiated KMC (cKMC). Promoting KMC at home without an understanding of its acceptability may lead to limited success. METHODS: We conducted formative research to assess the feasibility, acceptability and adoption of cKMC with the aim of designing an intervention package for a randomised controlled trial in LBW infants in Haryana, India. Qualitative methods included 40 in-depth interviews with recently delivered women and 6 focus group discussions, two each with fathers and grandfathers, grandmothers, and community health workers. A prototype intervention package to promote cKMC was developed and tested in 28 mother-infant pairs (of them, one mother had twins), using Household (HH) trials. RESULTS: We found that most mothers in the community recognized that babies born small required special care. In spite of not being aware of the practice of KMC, respondents felt that creating awareness of KMC benefits will promote practice. They expressed concerns about doing KMC for long periods because mothers needed rest after delivery. However, the cultural practice of recently delivered women not expected to be doing household chores and availability of other family members were identified as enablers. HH trials provided an opportunity to test the intervention package and showed high acceptability for KMC. Most mothers perceived benefits such as weight gain and increased activity in the infant. CONCLUSIONS: Community-initiated KMC is acceptable by mothers and adoption rates are high. Formative research is essential for developing a strategy for delivery of an intervention. TRIAL REGISTRATION: Trial registration number CTRI/2015/10/006267 . Name of Registry: Clinical Trials Registry - India. URL of Registry: http://ctri.nic.in/Clinicaltrials/login.php Date of Registration: 15/10/2015. Date of enrolment of the first participant to the trial: 18/04/2015.


Assuntos
Serviços de Saúde Comunitária , Promoção da Saúde/organização & administração , Recém-Nascido de Baixo Peso , Método Canguru , Mães/psicologia , Feminino , Grupos Focais , Humanos , Índia , Recém-Nascido , Masculino , Mães/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Pesquisa Qualitativa
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