Research Topics
| S FloydSummaryAffiliation: London School of Hygiene and Tropical Medicine Country: UK Publications
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Detail Information
Publications
Underestimation of HIV prevalence in surveys when some people already know their status, and ways to reduce the biasSian Floyd
London School of Hygiene and Tropical Medicine, Keppel Street, WC1E 7HT London, UK
AIDS 27:233-42. 2013..To quantify refusal bias due to prior HIV testing, and its effect on HIV prevalence estimates, in general-population surveys...
The effect of antiretroviral therapy provision on all-cause, AIDS and non-AIDS mortality at the population level--a comparative analysis of data from four settings in Southern and East AfricaSian Floyd
London School of Hygiene and Tropical Medicine, London, UK
Trop Med Int Health 17:e84-93. 2012..To provide a broad and up-to-date picture of the effect of antiretroviral therapy (ART) provision on population-level mortality in Southern and East Africa...- Persistence of the immune response induced by BCG vaccinationRosemary E Weir
London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
BMC Infect Dis 8:9. 2008.... - Differences between naive and memory T cell phenotype in Malawian and UK adolescents: a role for Cytomegalovirus?Anne Ben-Smith
Department of Infectious and Tropical Diseases, Keppel Street, London WC1E7HT, UK
BMC Infect Dis 8:139. 2008.... 
The social and economic impact of parental HIV on children in northern Malawi: retrospective population-based cohort studyS Floyd
London School of Hygiene and Tropical Medicine, London, UK
AIDS Care 19:781-90. 2007....- The long-term social and economic impact of HIV on the spouses of infected individuals in northern MalawiSian Floyd
London School of Hygiene and Tropical Medicine, London, UK
Trop Med Int Health 13:520-31. 2008..To assess the social and economic impact of HIV-related illness and death on the spouses of HIV-infected individuals... - BCG scars in northern Malawi: sensitivity and repeatability of scar reading, and factors affecting scar sizeS Floyd
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, UK
Int J Tuberc Lung Dis 4:1133-42. 2000..Karonga district, northern Malawi... - Population-level reduction in adult mortality after extension of free anti-retroviral therapy provision into rural areas in northern MalawiSian Floyd
Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
PLoS ONE 5:e13499. 2010..It is important to see if the impact changes with time since the start of treatment scale-up, and as treatment moves to smaller clinics... - Kinetics of delayed-type hypersensitivity to tuberculin induced by bacille Calmette-Guérin vaccination in northern MalawiSian Floyd
Department of Infectious and Tropical Diseases, Infectious Diseases Epidemiology Unit, London School of Hygiene and Tropical Medicine, London, United Kingdom
J Infect Dis 186:807-14. 2002..The inability of some persons to mount a persistent DTH response probably reflects genetic background and/or environmental exposure history... - The influence of previous exposure to environmental mycobacteria on the interferon-gamma response to bacille Calmette-Guérin vaccination in southern England and northern MalawiR E Weir
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
Clin Exp Immunol 146:390-9. 2006..These observations should assist the development and interpretation of human clinical trials of new vaccines against M. tuberculosis in areas of both low and high exposure to environmental mycobacteria... - Declining child mortality in northern Malawi despite high rates of infection with HIVA Jahn
Infectious Disease Epidemiology Unit, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, England
Bull World Health Organ 88:746-53. 2010..To determine whether routine surveys, such as the Demographic and Health Surveys (DHS), have underestimated child mortality in Malawi... - A comparison of dual skin test with mycobacterial antigens and tuberculin skin test alone in estimating prevalence of Mycobacterium tuberculosis infection from population surveysA L Bierrenbach
Department of Infectious and Tropical Disease, London School of Hygiene and Tropical Medicine, London, UK
Int J Tuberc Lung Dis 7:312-9. 2003..City of Manaus, Amazonas, Brazil... - Time delays between patient and laboratory selectively affect accuracy of helminth diagnosisR J Dacombe
London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
Trans R Soc Trop Med Hyg 101:140-5. 2007..This is particularly critical when samples are not preserved, even over short periods of time, and even with formalin preservation... - Immunogenicity of Danish-SSI 1331 BCG vaccine in the UK: comparison with Glaxo-Evans 1077 BCG vaccinePatricia Gorak-Stolinska
London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, and Redbridge Primary Care Trust, Goodmayes Hospital, Essex, UK
Vaccine 24:5726-33. 2006..There was no evidence of a difference in immunogenicity (IFN-gamma and DTH conversion rates) but evidence of lower reactogenicity (scar size) with Danish-SSI 1331 compared to Glaxo-Evans 1077 vaccines... - Patterns of helminth infection and relationship to BCG vaccination in Karonga District, northern MalawiA E Randall
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
Trans R Soc Trop Med Hyg 96:29-33. 2002.... - Interferon-gamma and skin test responses of schoolchildren in southeast England to purified protein derivatives from Mycobacterium tuberculosis and other species of mycobacteriaR E Weir
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
Clin Exp Immunol 134:285-94. 2003..marinum (45-60% responders). Heaf test and IFN-gamma responses were associated (P<0.001) for M. tuberculosis, MAIS and M. marinum. These findings have implications for appropriate implementation of vaccination against tuberculosis... - Tuberculosis transmission attributable to close contacts and HIV status, MalawiAmelia C Crampin
London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
Emerg Infect Dis 12:729-35. 2006..We estimate that 9%-13% of TB cases were attributable to recent transmission from identifiable close contacts and that nearly half of the TB cases arising from recent infection had acquired the infection from HIV-positive patients... - Trends in marriage and time spent single in sub-Saharan Africa: a comparative analysis of six population-based cohort studies and nine Demographic and Health SurveysM Marston
Centre for Population Studies, London School of Hygiene and Tropical Medicine, London, UK
Sex Transm Infect 85:i64-71. 2009..To describe trends in age at first sex (AFS), age at first marriage (AFM) and time spent single between events and to compare age-specific trends in marital status in six cohort studies... - Assessment and evaluation of contact as a risk factor for tuberculosis in rural AfricaA C Crampin
Karonga Prevention Study, Chilumba, Malawi
Int J Tuberc Lung Dis 12:612-8. 2008..A rural district in Malawi... - Ascertainment of childhood vaccination histories in northern MalawiA Jahn
Karonga Prevention Study, Chilumba, Malawi
Trop Med Int Health 13:129-38. 2008..To assess factors related to recorded vaccine uptake, which may confound the evaluation of vaccine impact... - Recurrent TB: relapse or reinfection? The effect of HIV in a general population cohort in MalawiAmelia C Crampin
Karonga Prevention Study, Chilumba, Malawi
AIDS 24:417-26. 2010..To estimate rates of recurrent tuberculosis due to reinfection and relapse, by HIV status, in a general population... - Trends in tuberculosis and the influence of HIV infection in northern Malawi, 1988-2001Judith R Glynn
London School of Hygiene and Tropical Medicine, UK
AIDS 18:1459-63. 2004..Instead it has risen and is predominantly affecting young adults and women. There is some evidence that the HIV-associated TB epidemic may have passed its peak... - Complex cytokine profiles induced by BCG vaccination in UK infantsMaeve K Lalor
Immunology Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
Vaccine 28:1635-41. 2010..The pattern of cytokine induction following BCG vaccination is complex and measurement of one of two cytokines does not reveal the whole picture of vaccine-induced protection... - Population differences in immune responses to Bacille Calmette-Guérin vaccination in infancyMaeve K Lalor
Immunology Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
J Infect Dis 199:795-800. 2009..We conclude that population differences in immune responses after BCG vaccination are observed among infants, as well as among young adults... - Mycobacterial purified protein derivatives stimulate innate immunity: Malawians show enhanced tumor necrosis factor alpha, interleukin-1beta (IL-1beta), and IL-10 responses compared to those of adolescents in the United KingdomRosemary E Weir
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
Infect Immun 72:1807-11. 2004..Priming for regulatory IL-10 may contribute to the smaller increase in gamma interferon responses in Malawians compared to United Kingdom subjects following BCG vaccination... - Is education the link between orphanhood and HIV/HSV-2 risk among female adolescents in urban Zimbabwe?Isolde Birdthistle
London School of Hygiene and Tropical Medicine, London, United Kingdom
Soc Sci Med 68:1810-8. 2009.... - Use of antenatal clinic surveillance to assess the effect of sexual behavior on HIV prevalence in young women in Karonga district, MalawiAmelia Catharine Crampin
Department of Epidemiology and Public Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
J Acquir Immune Defic Syndr 48:196-202. 2008..Sexual behavior monitoring to explain HIV distribution and trends is seldom attempted in ANC surveys. We explore the use of marital history in ANC surveillance as a proxy for sexual behavior... - Population-level effect of HIV on adult mortality and early evidence of reversal after introduction of antiretroviral therapy in MalawiAndreas Jahn
London School of Hygiene and Tropical Medicine, London, UK
Lancet 371:1603-11. 2008..We aimed to investigate mortality in a population before and after the introduction of free antiretroviral therapy, and therefore to assess the effects of such programmes on survival at the population level... - From affected to infected? Orphanhood and HIV risk among female adolescents in urban ZimbabweIsolde J Birdthistle
Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
AIDS 22:759-66. 2008..Despite the 15 million children orphaned by AIDS, and fears of sexual vulnerability, little is known about the link between orphanhood and HIV risk... - DNA fingerprint changes in tuberculosis: reinfection, evolution, or laboratory error?Judith R Glynn
Infectious Disease Epidemiology Unit, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
J Infect Dis 190:1158-66. 2004..We explored the importance of these factors... - Mycobacterium tuberculosis Beijing genotype, northern MalawiJudith R Glynn
London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
Emerg Infect Dis 11:150-3. 2005..All the Beijing genotype strains were fully drug sensitive. Contact histories, TB type, and case-fatality rates were similar for Beijing and non-Beijing genotype TB... - HIV and mortality of mothers and children: evidence from cohort studies in Uganda, Tanzania, and MalawiBasia Zaba
Centre for Population Studies, London School of Hygiene and Tropical Medicine, 49 51 Bedford Square, London WC1B 3DP, UK
Epidemiology 16:275-80. 2005..However, the census and household survey data that generally are used to produce estimates of child mortality do not permit precise measures of the adverse effect of HIV on child mortality... - The effects of high HIV prevalence on orphanhood and living arrangements of children in Malawi, Tanzania, and South AfricaVictoria Hosegood
London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
Popul Stud (Camb) 61:327-36. 2007..For example, we find no evidence that the prevalence of child-headed households is significant or has increased in the three study areas... - Comparison of IFN-gamma responses to mycobacterial antigens as markers of response to BCG vaccinationRosemary E Weir
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
Tuberculosis (Edinb) 88:31-8. 2008..We therefore conclude that Mtb PPD is the antigen preparation of choice for assessing the immunogenicity of BCG vaccination... - Child mortality in rural Malawi: HIV closes the survival gap between the socio-economic strataAndreas Jahn
Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
PLoS ONE 5:e11320. 2010..As HIV-related deaths increase in a population the usual association between low socioeconomic status and child mortality may change, particularly as death rates from other causes decline... - Implication of new WHO growth standards on identification of risk factors and estimated prevalence of malnutrition in rural Malawian infantsMarc André Prost
Epidemiology and Population Health Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
PLoS ONE 3:e2684. 2008..We assessed how switching from the NCHS to the newly released WHO Growth Standards affects the estimated prevalence of wasting, underweight and stunting, and the pattern of risk factors identified... - Gamma interferon responses induced by a panel of recombinant and purified mycobacterial antigens in healthy, non-mycobacterium bovis BCG-vaccinated Malawian young adultsGillian F Black
Karonga Prevention Study, Chilumba, Malawi
Clin Diagn Lab Immunol 10:602-11. 2003..tuberculosis antigens tested it provided the best indication of exposure to, or infection with, M. tuberculosis... - Long-term follow-up of HIV-positive and HIV-negative individuals in rural MalawiAmelia C Crampin
Karonga Prevention Study, PO Box 46, Chilumba, Malawi
AIDS 16:1545-50. 2002..Mortality rates in HIV-positive individuals increased with age, but relative mortality changed little with age... - BCG-induced increase in interferon-gamma response to mycobacterial antigens and efficacy of BCG vaccination in Malawi and the UK: two randomised controlled studiesGillian F Black
Karonga Prevention Study, Chilumba, Malawi
Lancet 359:1393-401. 2002..It is likely that differential sensitisation due to exposure to environmental mycobacteria is the most important determinant of the observed differences in protection by BCG between populations... - Distribution of environmental mycobacteria in Karonga District, northern MalawiBenson Z Chilima
Plant Pathogen Interactions Division, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, United Kingdom
Appl Environ Microbiol 72:2343-50. 2006..This study revealed a complex pattern for the environmental mycobacterial flora but identified no clear differences between the northern and southern parts of Karonga District... - Large-scale candidate gene study of tuberculosis susceptibility in the Karonga district of northern MalawiJodene Fitness
Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
Am J Trop Med Hyg 71:341-9. 2004..Genetic susceptibility to TB in Africans appears polygenic. The relevant genes and variants may vary significantly between populations, and may be affected by HIV infection status... - The long-term impact of HIV and orphanhood on the mortality and physical well-being of children in rural MalawiAmelia C Crampin
Karonga Prevention Study, Chilumba, Karonga, Malawi
AIDS 17:389-97. 2003..Our findings suggest that, in terms of physical well-being, the extended family in this society has not discriminated against surviving children whose parents have been ill or have died as a result of HIV/AIDS... - Large-scale candidate gene study of leprosy susceptibility in the Karonga district of northern MalawiJodene Fitness
Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
Am J Trop Med Hyg 71:330-40. 2004..These data provide evidence of inter-population heterogeneity in leprosy susceptibility... - Cotrimoxazole prophylaxis reduces mortality in human immunodeficiency virus-positive tuberculosis patients in Karonga District, MalawiFrank B D Mwaungulu
Karonga Prevention Study, Karonga, Malawi
Bull World Health Organ 82:354-63. 2004..Cotrimoxazole prophylaxis should therefore be added to the routine care of HIV-positive TB patients... - The PPD-specific T-cell clonal response in UK and Malawian subjects following BCG vaccination: a new repertoire evolves over 12 monthsAndrea R Bennett
Edward Jenner Institute for Vaccine Research, Compton, Berkshire RG20 7NN, UK
Vaccine 24:2617-26. 2006..The magnitude of the clonal response did not correlate well with results of the other assays. These data indicate that single assays may not be reliable and that a stable memory T-cell repertoire is slow to develop... - CD209 genetic polymorphism and tuberculosis diseaseFredrik O Vannberg
Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
PLoS ONE 3:e1388. 2008..The present study investigates the role of the CD209 -336A/G variant in susceptibility to tuberculosis in a large sample of individuals from sub-Saharan Africa...