Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Anna C Seale is active.

Publication


Featured researches published by Anna C Seale.


The Lancet Respiratory Medicine | 2014

Effectiveness of neuraminidase inhibitors in reducing mortality in patients admitted to hospital with influenza A H1N1pdm09 virus infection: a meta-analysis of individual participant data

Stella G. Muthuri; Sudhir Venkatesan; Puja R. Myles; Jo Leonardi-Bee; Tarig Saleh Al Khuwaitir; Adbullah Al Mamun; Ashish P. Anovadiya; Eduardo Azziz-Baumgartner; Clarisa Báez; Matteo Bassetti; Bojana Beovic; Barbara Bertisch; Isabelle Bonmarin; Robert Booy; Víctor Hugo Borja-Aburto; Heinz Burgmann; Bin Cao; Jordi Carratalà; Justin T. Denholm; Samuel R. Dominguez; Péricles Almeida Delfino Duarte; Gal Dubnov-Raz; Marcela Echavarria; Sergio Fanella; Zhancheng Gao; Patrick Gérardin; Maddalena Giannella; Sophie Gubbels; Jethro Herberg; Anjarath L. Higuera Iglesias

BACKGROUND Neuraminidase inhibitors were widely used during the 2009-10 influenza A H1N1 pandemic, but evidence for their effectiveness in reducing mortality is uncertain. We did a meta-analysis of individual participant data to investigate the association between use of neuraminidase inhibitors and mortality in patients admitted to hospital with pandemic influenza A H1N1pdm09 virus infection. METHODS We assembled data for patients (all ages) admitted to hospital worldwide with laboratory confirmed or clinically diagnosed pandemic influenza A H1N1pdm09 virus infection. We identified potential data contributors from an earlier systematic review of reported studies addressing the same research question. In our systematic review, eligible studies were done between March 1, 2009 (Mexico), or April 1, 2009 (rest of the world), until the WHO declaration of the end of the pandemic (Aug 10, 2010); however, we continued to receive data up to March 14, 2011, from ongoing studies. We did a meta-analysis of individual participant data to assess the association between neuraminidase inhibitor treatment and mortality (primary outcome), adjusting for both treatment propensity and potential confounders, using generalised linear mixed modelling. We assessed the association with time to treatment using time-dependent Cox regression shared frailty modelling. FINDINGS We included data for 29,234 patients from 78 studies of patients admitted to hospital between Jan 2, 2009, and March 14, 2011. Compared with no treatment, neuraminidase inhibitor treatment (irrespective of timing) was associated with a reduction in mortality risk (adjusted odds ratio [OR] 0·81; 95% CI 0·70-0·93; p=0·0024). Compared with later treatment, early treatment (within 2 days of symptom onset) was associated with a reduction in mortality risk (adjusted OR 0·48; 95% CI 0·41-0·56; p<0·0001). Early treatment versus no treatment was also associated with a reduction in mortality (adjusted OR 0·50; 95% CI 0·37-0·67; p<0·0001). These associations with reduced mortality risk were less pronounced and not significant in children. There was an increase in the mortality hazard rate with each days delay in initiation of treatment up to day 5 as compared with treatment initiated within 2 days of symptom onset (adjusted hazard ratio [HR 1·23] [95% CI 1·18-1·28]; p<0·0001 for the increasing HR with each days delay). INTERPRETATION We advocate early instigation of neuraminidase inhibitor treatment in adults admitted to hospital with suspected or proven influenza infection. FUNDING F Hoffmann-La Roche.


Lancet Infectious Diseases | 2009

Maternal and early onset neonatal bacterial sepsis: burden and strategies for prevention in sub-Saharan Africa

Anna C Seale; Michael K Mwaniki; Charles R. Newton; James A. Berkley

Maternal and child health are high priorities for international development. Through a Review of published work, we show substantial gaps in current knowledge on incidence (cases per live births), aetiology, and risk factors for both maternal and early onset neonatal bacterial sepsis in sub-Saharan Africa. Although existing published data suggest that sepsis causes about 10% of all maternal deaths and 26% of neonatal deaths, these are likely to be considerable underestimates because of methodological limitations. Successful intervention strategies in resource-rich settings and early studies in sub-Saharan Africa suggest that the burden of maternal and early onset neonatal bacterial sepsis could be reduced through simple interventions, including antiseptic and antibiotic treatment. An effective way to expedite evidence to guide interventions and determine the incidence, aetiology, and risk factors for sepsis in sub-Saharan Africa would be through a multiarmed factorial intervention trial aimed at reducing both maternal and early onset neonatal bacterial sepsis in sub-Saharan Africa.


BMC Pregnancy and Childbirth | 2015

Count every newborn; A measurement improvement roadmap for coverage data

Sarah G Moxon; Harriet Ruysen; Kate Kerber; Agbessi Amouzou; Suzanne Fournier; John Grove; Allisyn C. Moran; Lara M. E. Vaz; Hannah Blencowe; Niall Conroy; A Metin Gülmezoglu; Joshua P. Vogel; Barbara Rawlins; Rubayet Sayed; Kathleen Hill; Donna Vivio; Shamim Qazi; Deborah Sitrin; Anna C Seale; Steve Wall; Troy Jacobs; Juan Gabriel Ruiz Peláez; Tanya Guenther; Patricia S. Coffey; Penny Dawson; Tanya Marchant; Peter Waiswa; Ashok K. Deorari; Christabel Enweronu-Laryea; Shams El Arifeen

BackgroundThe Every Newborn Action Plan (ENAP), launched in 2014, aims to end preventable newborn deaths and stillbirths, with national targets of ≤12 neonatal deaths per 1000 live births and ≤12 stillbirths per 1000 total births by 2030. This requires ambitious improvement of the data on care at birth and of small and sick newborns, particularly to track coverage, quality and equity.MethodsIn a multistage process, a matrix of 70 indicators were assessed by the Every Newborn steering group. Indicators were graded based on their availability and importance to ENAP, resulting in 10 core and 10 additional indicators. A consultation process was undertaken to assess the status of each ENAP core indicator definition, data availability and measurement feasibility. Coverage indicators for the specific ENAP treatment interventions were assigned task teams and given priority as they were identified as requiring the most technical work. Consultations were held throughout.ResultsENAP published 10 core indicators plus 10 additional indicators. Three core impact indicators (neonatal mortality rate, maternal mortality ratio, stillbirth rate) are well defined, with future efforts needed to focus on improving data quantity and quality. Three core indicators on coverage of care for all mothers and newborns (intrapartum/skilled birth attendance, early postnatal care, essential newborn care) have defined contact points, but gaps exist in measuring content and quality of the interventions. Four core (antenatal corticosteroids, neonatal resuscitation, treatment of serious neonatal infections, kangaroo mother care) and one additional coverage indicator for newborns at risk or with complications (chlorhexidine cord cleansing) lack indicator definitions or data, especially for denominators (population in need). To address these gaps, feasible coverage indicator definitions are presented for validity testing. Measurable process indicators to help monitor health service readiness are also presented. A major measurement gap exists to monitor care of small and sick babies, yet signal functions could be tracked similarly to emergency obstetric care.ConclusionsThe ENAP Measurement Improvement Roadmap (2015-2020) outlines tools to be developed (e.g., improved birth and death registration, audit, and minimum perinatal dataset) and actions to test, validate and institutionalise proposed coverage indicators. The roadmap presents a unique opportunity to strengthen routine health information systems, crosslinking these data with civil registration and vital statistics and population-based surveys. Real measurement change requires intentional transfer of leadership to countries with the greatest disease burden and will be achieved by working with centres of excellence and existing networks.


Pediatric Research | 2013

Neonatal severe bacterial infection impairment estimates in South Asia, sub-Saharan Africa, and Latin America for 2010.

Anna C Seale; Hannah Blencowe; Anita K. M. Zaidi; Hammad A. Ganatra; Sana Syed; Cyril Engmann; Charles R. Newton; Stefania Vergnano; Barbara J. Stoll; Simon Cousens; Joy E Lawn

Background:Survivors of neonatal infections are at risk of neurodevelopmental impairment (NDI), a burden not previously systematically quantified and yet important for program priority setting. Systematic reviews and meta-analyses were undertaken and applied in a three-step compartmental model to estimate NDI cases after severe neonatal bacterial infection in South Asia, sub-Saharan Africa, and Latin America in neonates of >32 wk gestation (or >1,500 g).Methods:We estimated cases of sepsis, meningitis, pneumonia, or no severe bacterial infection from among estimated cases of possible severe bacterial infection ((pSBI) step 1). We applied respective case fatality risks ((CFRs) step 2) and the NDI risk among survivors (step 3). For neonatal tetanus, incidence estimates were based on the estimated deaths, CFRs, and risk of subsequent NDI.Results:For 2010, we estimated 1.7 million (uncertainty range: 1.1–2.4 million) cases of neonatal sepsis, 200,000 (21,000–350,000) cases of meningitis, 510,000 cases (150,000–930,000) of pneumonia, and 79,000 cases (70,000–930,000) of tetanus in neonates >32 wk gestation (or >1,500 g). Among the survivors, we estimated moderate to severe NDI after neonatal meningitis in 23% (95% confidence interval: 19–26%) of survivors, 18,000 (2,700–35,000) cases, and after neonatal tetanus in 16% (6–27%), 4,700 cases (1,700–8,900).Conclusion:Data are lacking for impairment after neonatal sepsis and pneumonia, especially among those of >32 wk gestation. Improved recognition and treatment of pSBI will reduce neonatal mortality. Lack of follow-up data for survivors of severe bacterial infections, particularly sepsis, was striking. Given the high incidence of sepsis, even minor NDI would be of major public health importance. Prevention of neonatal infection, improved case management, and support for children with NDI are all important strategies, currently receiving limited policy attention.


Clinical Infectious Diseases | 2017

Estimates of the Burden of Group B Streptococcal Disease Worldwide for Pregnant Women, Stillbirths, and Children

Anna C Seale; Fiorella Bianchi-Jassir; Neal J Russell; Maya Kohli-Lynch; Cally J Tann; Jenny Hall; Lola Madrid; Hannah Blencowe; Simon Cousens; Carol J. Baker; Linda Bartlett; Clare L. Cutland; Michael G. Gravett; Paul T Heath; Margaret Ip; Kirsty Le Doare; Shabir A. Madhi; Craig E. Rubens; Samir K. Saha; Stephanie J. Schrag; Ajoke Sobanjo-ter Meulen; Johan Vekemans; Joy E Lawn

Group B Streptococcus is an important cause of disease in pregnant women, stillbirth, and infants. These first estimates show the magnitude and the potential impact of maternal vaccination.


Nature microbiology | 2016

Maternal colonization with Streptococcus agalactiae and associated stillbirth and neonatal disease in coastal Kenya

Anna C Seale; Angela Koech; Anna E. Sheppard; Hellen C. Barsosio; Langat J; Anyango E; Mwakio S; Salim Mwarumba; Susan C. Morpeth; Anampiu K; Alison Vaughan; Adam Giess; Polycarp Mogeni; Walusuna L; Mwangudzah H; Mwanzui D; Salim M; Bryn Kemp; Cheron Jones; Neema Mturi; Benjamin Tsofa; Edward Mumbo; Mulewa D; Bandika; Soita M; Owiti M; Onzere N; A. S. Walker; Stephanie J. Schrag; Stephen Kennedy

Streptococcus agalactiae (group B streptococcus, GBS) causes neonatal disease and stillbirth, but its burden in sub-Saharan Africa is uncertain. We assessed maternal recto–vaginal GBS colonization (7,967 women), stillbirth and neonatal disease. Whole-genome sequencing was used to determine serotypes, sequence types and phylogeny. We found low maternal GBS colonization prevalence (934/7,967, 12%), but comparatively high incidence of GBS-associated stillbirth and early onset neonatal disease (EOD) in hospital (0.91 (0.25–2.3)/1,000 births and 0.76 (0.25–1.77)/1,000 live births, respectively). However, using a population denominator, EOD incidence was considerably reduced (0.13 (0.07–0.21)/1,000 live births). Treated cases of EOD had very high case fatality (17/36, 47%), especially within 24 h of birth, making under-ascertainment of community-born cases highly likely, both here and in similar facility-based studies. Maternal GBS colonization was less common in women with low socio-economic status, HIV infection and undernutrition, but when GBS-colonized, they were more probably colonized by the most virulent clone, CC17. CC17 accounted for 267/915 (29%) of maternal colonizing (265/267 (99%) serotype III; 2/267 (0.7%) serotype IV) and 51/73 (70%) of neonatal disease cases (all serotype III). Trivalent (Ia/II/III) and pentavalent (Ia/Ib/II/III/V) vaccines would cover 71/73 (97%) and 72/73 (99%) of disease-causing serotypes, respectively. Serotype IV should be considered for inclusion, with evidence of capsular switching in CC17 strains.


Journal of Clinical Laboratory Analysis | 2008

Effects of cryopreservation on CD4+ CD25+ T cells of HIV-1 infected individuals.

Anna C Seale; Bouke C. de Jong; Irfan Zaidi; Melody G. Duvall; Hilton Whittle; Sarah Rowland-Jones; Assan Jaye

The role of T regulatory cells (Tregs) in human immunodeficiency virus (HIV)‐1 infection, although not entirely clear, has recently been highlighted. Despite their lack of specificity, fluorochrome‐labeled CD4 and CD25 antibodies are common flow cytometric reagents used to identify these cells with immunosuppressive potential. Cryopreservation has previously been shown to alter the proportions of lymphocytes with certain phenotypes expressed in peripheral blood mononuclear cells (PBMCs). The aim of this study was to assess the effect of cryopreservation on CD4+ CD25+ T cells in PBMCs from HIV‐1+ individuals to guide the design of future studies on Tregs. We recruited 30 HIV‐1+ individuals and nine healthy controls. CD25 expression in CD4+ T cells was compared between fresh and frozen/thawed PBMC samples from the same time point. In this study, cryopreservation significantly decreased the proportion of CD4+ CD25+ T cells in PBMC samples from HIV‐1 infected subjects. This finding suggests that studies of CD4+ CD25+ T cells should be carried out on fresh samples to avoid bias introduced by cryopreservation. J. Clin. Lab. Anal. 22:153–158, 2008.


Clinical Infectious Diseases | 2017

Maternal Colonization With Group B Streptococcus and Serotype Distribution Worldwide: Systematic Review and Meta-analyses

Jennifer Hall; Nadine Hack Adams; Linda Bartlett; Anna C Seale; Theresa Lamagni; Fiorella Bianchi-Jassir; Joy E Lawn; Carol J. Baker; Clare L. Cutland; Paul T Heath; Margaret Ip; Kirsty Le Doare; Shabir A. Madhi; Craig E. Rubens; Samir K. Saha; Stephanie J. Schrag; Ajoke Sobanjo-ter Meulen; Johan Vekemans; Michael G. Gravett

Abstract Background Maternal rectovaginal colonization with group B Streptococcus (GBS) is the most common pathway for GBS disease in mother, fetus, and newborn. This article, the second in a series estimating the burden of GBS, aims to determine the prevalence and serotype distribution of GBS colonizing pregnant women worldwide. Methods We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus), organized Chinese language searches, and sought unpublished data from investigator groups. We applied broad inclusion criteria to maximize data inputs, particularly from low- and middle-income contexts, and then applied new meta-analyses to adjust for studies with less-sensitive sampling and laboratory techniques. We undertook meta-analyses to derive pooled estimates of maternal GBS colonization prevalence at national and regional levels. Results The dataset regarding colonization included 390 articles, 85 countries, and a total of 299924 pregnant women. Our adjusted estimate for maternal GBS colonization worldwide was 18% (95% confidence interval [CI], 17%–19%), with regional variation (11%–35%), and lower prevalence in Southern Asia (12.5% [95% CI, 10%–15%]) and Eastern Asia (11% [95% CI, 10%–12%]). Bacterial serotypes I–V account for 98% of identified colonizing GBS isolates worldwide. Serotype III, associated with invasive disease, accounts for 25% (95% CI, 23%–28%), but is less frequent in some South American and Asian countries. Serotypes VI–IX are more common in Asia. Conclusions GBS colonizes pregnant women worldwide, but prevalence and serotype distribution vary, even after adjusting for laboratory methods. Lower GBS maternal colonization prevalence, with less serotype III, may help to explain lower GBS disease incidence in regions such as Asia. High prevalence worldwide, and more serotype data, are relevant to prevention efforts.


Clinical Infectious Diseases | 2017

Infant Group B Streptococcal Disease Incidence and Serotypes Worldwide: Systematic Review and Meta-analyses

Lola Madrid; Anna C Seale; Maya Kohli-Lynch; Karen Edmond; Joy E Lawn; Paul T. Heath; Shabir A. Madhi; Carol J. Baker; Linda Bartlett; Clare L. Cutland; Michael G. Gravett; Margaret Ip; Kirsty Le Doare; Craig E. Rubens; Samir K. Saha; Ajoke Sobanjo-ter Meulen; Johan Vekemans; Stephanie J. Schrag

Abstract Background Group B Streptococcus (GBS) remains a leading cause of neonatal sepsis in high-income contexts, despite declines due to intrapartum antibiotic prophylaxis (IAP). Recent evidence suggests higher incidence in Africa, where IAP is rare. We investigated the global incidence of infant invasive GBS disease and the associated serotypes, updating previous estimates. Methods We conducted systematic literature reviews (PubMed/Medline, Embase, Latin American and Caribbean Health Sciences Literature [LILACS], World Health Organization Library Information System [WHOLIS], and Scopus) and sought unpublished data regarding invasive GBS disease in infants aged 0–89 days. We conducted random-effects meta-analyses of incidence, case fatality risk (CFR), and serotype prevalence. Results We identified 135 studies with data on incidence (n = 90), CFR (n = 64), or serotype (n = 45). The pooled incidence of invasive GBS disease in infants was 0.49 per 1000 live births (95% confidence interval [CI], .43–.56), and was highest in Africa (1.12) and lowest in Asia (0.30). Early-onset disease incidence was 0.41 (95% CI, .36–.47); late-onset disease incidence was 0.26 (95% CI, .21–.30). CFR was 8.4% (95% CI, 6.6%–10.2%). Serotype III (61.5%) dominated, with 97% of cases caused by serotypes Ia, Ib, II, III, and V. Conclusions The incidence of infant GBS disease remains high in some regions, particularly Africa. We likely underestimated incidence in some contexts, due to limitations in case ascertainment and specimen collection and processing. Burden in Asia requires further investigation.


Pediatric Infectious Disease Journal | 2012

Treatment Failure among Kenyan Children with Severe Pneumonia – a Cohort Study

Clare Webb; Mwanajuma Ngama; Anthony Ngatia; Mohammed Shebbe; Susan Morpeth; Salim Mwarumba; Ann Bett; D. James Nokes; Anna C Seale; Sidi Kazungu; Patrick Munywoki; Laura L. Hammitt; J. Anthony G. Scott; James A. Berkley

Background: Pneumonia is the leading cause of childhood mortality worldwide. The World Health Organization recommends presumptive treatment based on clinical syndromes. Recent studies raise concerns over the frequency of treatment failure in Africa. Methods: We applied a definition of treatment failure to data prospectively collected from children who were 2–59 months of age with severe, or very severe, pneumonia admitted to Kilifi District Hospital, Kenya, from May 2007 through May 2008 and treated using World Health Organization guidelines. The primary outcome was treatment failure at 48 hours. Results: Of 568 children, median age 11 months, 165 (29%) had very severe pneumonia, 30 (5.3%) a positive HIV test and 62 (11%) severe malnutrition. One hundred eleven (20%; 95% confidence interval: 17–23%) children failed treatment at 48 hours and 34 (6.0%) died; 22 (65%) deaths occurred before 48 hours. Of 353 children with severe pneumonia, without HIV or severe malnutrition, 42 (12%) failed to respond at 48 hours, 15 (4.3%) failed at 5 days and 1 child (0.3%) died. Among 215 children with either severe pneumonia complicated by HIV or severe malnutrition, or very severe pneumonia, 69 (32%) failed to treatment at 48 hours, 47 (22%) failed at 5 days and 33 (16%) died. Treatment failure at 48 hours was associated with shock, bacteremia, very severe pneumonia, oxygen saturation in hemoglobin <95%, severe malnutrition, HIV and age <1 year in multivariable models. Conclusions: In this setting, few children with uncomplicated severe pneumonia fail treatment or die under current guidelines. Deaths mainly occurred early and may be reduced by improving prevention, prehospital care and treatment of sepsis.

Collaboration


Dive into the Anna C Seale's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Stephanie J. Schrag

Centers for Disease Control and Prevention

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Shabir A. Madhi

University of the Witwatersrand

View shared research outputs
Top Co-Authors

Avatar

Clare L. Cutland

University of the Witwatersrand

View shared research outputs
Top Co-Authors

Avatar

Carol J. Baker

Baylor College of Medicine

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge