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Dive into the research topics where Jimmy Whitworth is active.

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Featured researches published by Jimmy Whitworth.


AIDS | 2006

Herpes simplex virus 2 infection increases HIV acquisition in men and women: systematic review and meta-analysis of longitudinal studies.

Esther E. Freeman; Helen A. Weiss; Glynn; Pl Cross; Jimmy Whitworth; Richard Hayes

Objective:To estimate the sex-specific effect of herpes simplex virus type 2 (HSV-2) on the acquisition of HIV infection. Background:The increased number of longitudinal studies available since the last meta-analysis was published allows for the calculation of age- and sexual behaviour-adjusted relative risks (RR) separately for men and women. Design:Systematic review and meta-analysis of longitudinal studies. Methods:PubMed, Embase and relevant conference abstracts were systematically searched to identify longitudinal studies in which the relative timing of HSV-2 infection and HIV infection could be established. Where necessary, authors were contacted for separate estimates in men and women, adjusted for age and a measure of sexual behaviour. Summary adjusted RR were calculated using random-effects meta-analyses where appropriate. Studies on recent HSV-2 incidence as a risk factor for HIV acquisition were also collated. Results:Of 19 eligible studies identified, 18 adjusted for age and at least one measure of sexual behaviour after author contact. Among these, HSV-2 seropositivity was a statistically significant risk factor for HIV acquisition in general population studies of men [summary adjusted RR, 2.7; 95% confidence interval (CI), 1.9–3.9] and women (RR, 3.1; 95% CI, 1.7–5.6), and among men who have sex with men (RR, 1.7; 95% CI, 1.2–2.4). The effect in high-risk women showed significant heterogeneity, with no overall evidence of an association. Conclusions:Prevalent HSV-2 infection is associated with a three-fold increased risk of HIV acquisition among both men and women in the general population, suggesting that, in areas of high HSV-2 prevalence, a high proportion of HIV is attributable to HSV-2.


The Lancet | 2000

Effect of HIV-1 and increasing immunosuppression on malaria parasitaemia and clinical episodes in adults in rural Uganda: a cohort study.

Jimmy Whitworth; Dilys Morgan; Maria A. Quigley; Adrian Smith; Billy N. Mayanja; Henry Eotu; Nicholas Omoding; Martin Okongo; Samuel S. Malamba; Amato Ojwiya

BACKGROUND An association between HIV-1 and malaria is expected in theory, but has not been convincingly shown in practice. We studied the effects of HIV-1 infection and advancing immunosuppression on falciparum parasitaemia and clinical malaria. METHODS HIV-1-positive and HIV-1-negative adults selected from a population-based cohort in rural Uganda were invited to attend a clinic every 3 months (routine visits) and whenever they were sick (interim visits). At each visit, information was collected on recent fever, body temperature, and malaria parasites. Participants were assigned a clinical stage at each routine visit and had regular CD4-cell measurements. FINDINGS 484 participants made 7220 routine clinic visits between 1990 and 1998. Parasitaemia was more common at visits by HIV-1-positive individuals (328 of 2788 [11.8%] vs 231 of 3688 [6.3%], p<0.0001). At HIV-1-positive visits, lower CD4-cell counts were associated with higher parasite densities, compared with HIV-1-negative visits (p=0.0076). Clinical malaria was significantly more common at HIV-1-positive visits (55 of 2788 [2.0%] vs 26 of 3688 [0.7%], p=0.0003) and the odds of having clinical malaria increased with falling CD4-cell count (p=0.0002) and advancing clinical stage (p=0.0024). Participants made 3377 interim visits. The risk of clinical malaria was significantly higher at visits by HIV-1-positive individuals than HIV-1-negative individuals (4.0% vs 1.9%, p=0.009). The risk of clinical malaria tended to increase with falling CD4-cell counts (p=0.052). INTERPRETATION HIV-1 infection is associated with an increased frequency of clinical malaria and parasitaemia. This association tends to become more pronounced with advancing immunosuppression, and could have important public-health implications for sub-Saharan Africa.


The Lancet | 2000

23-valent pneumococcal polysaccharide vaccine in HIV-1-infected Ugandan adults: double-blind, randomised and placebo controlled trial.

Neil French; Jessica Nakiyingi; Lucy M. Carpenter; Eric Lugada; Christine Watera; K Moi; Michael Moore; D Antvelink; Daan W. Mulder; Edward N. Janoff; Jimmy Whitworth; Charles F. Gilks

BACKGROUND Infection with Streptococcus pneumoniae is a frequent and serious problem for HIV-immunosuppressed adults. Vaccination is recommended in the USA and Europe, but there are no prospective data that show vaccine efficacy. METHODS 1392 (937 female) HIV-1-infected adults in Entebbe, Uganda, were enrolled. 697 received 23-valent pneumococcal polysaccharide vaccine and 695 received placebo. The primary endpoint was first event invasive pneumococcal disease. Secondary endpoints included vaccine serogroup-specific invasive disease, all (probable and definite) pneumococcal events, all-cause pneumonia, and death. FINDINGS First invasive events occurred in 25 individuals (24 bacteraemias, one pyomyositis), 15 in the vaccine arm and ten in the placebo arm (hazard ratio [HR] 1.47; 95% CI 0.7-3.3). 22 isolates (88%) were of vaccine-specific serogroups with 15 events in the vaccine arm compared with seven in the placebo arm (HR 2.10; 0.9-5.2). All pneumococcal events had a similar distribution (20 vs 14; HR 1.41; 0.7-2.8) though all-cause pneumonia was significantly more frequent in the vaccine arm (40 vs 21; HR 1.89; 1.1-3.2). Mortality was unaffected by vaccination. INTERPRETATION 23-valent pneumococcal polysaccharide vaccination is ineffective in HIV-1-infected Ugandan adults and probably has little, or no, public health value elsewhere in sub-Saharan Africa. Increased rates of pneumococcal disease in vaccine recipients may necessitate a reappraisal of this intervention in other settings.


AIDS | 2002

HIV-1 infection in rural Africa: is there a difference in median time to AIDS and survival compared with that in industrialized countries?

Dilys Morgan; Cedric Mahe; Billy N. Mayanja; J. Martin Okongo; Rosemary Lubega; Jimmy Whitworth

Objectives To describe the progression times of HIV-1 infection from seroconversion to AIDS and to death, and time from first developing AIDS to death in rural Uganda. Also, to describe the proportion of individuals within the cohort dying with AIDS and the CD4 lymphocyte count before death. Design A prospective, longitudinal, population-based cohort. Methods Since 1990, 107 HIV-prevalent cases, 168 incident cases and 235 HIV-seronegative controls have been recruited into a cohort in rural Uganda. Participants are recruited from the general population and they are reviewed routinely every 3 months and at other times when ill. Results The median time from seroconversion to death was 9.8 years. Age over 40 years at seroconversion was associated with more rapid progression (P < 0.001, log rank test). For the first 4 years of the study, HIV contributed little to the death rates in the HIV incident cases, but after 5 years, the contribution of HIV became greater and was particularly marked in the oldest age group. Survival rates in the cohort were similar to those in the general population. The median time from seroconversion to AIDS was 9.4 years and from AIDS to death was 9.2 months. Of those infected with HIV-1, 80% died with AIDS and 20% had a CD4 count < 10 × 106 cells/l. Conclusions Survival with HIV-1 infection is similar in Africa to industrialized countries before the use of antiretroviral therapy; when they do die, many of those in Africa are severely immunosuppressed and most have clinical features of AIDS.


AIDS | 2002

Cryptococcal infection in a cohort of HIV-1-infected Ugandan adults

Neil French; Katherine J. Gray; Christine Watera; Jessica Nakiyingi; Eric Lugada; Michael Moore; David G. Lalloo; Jimmy Whitworth; Charles F. Gilks

Objective Despite the recognition of Cryptococcus neoformans as a major cause of meningitis in HIV-infected adults in sub-Saharan Africa, little is known about the relative importance of this potentially preventable infection as a cause of mortality and suffering in HIV-infected adults in this region. Design A cohort study of 1372 HIV-1-infected adults, enrolled and followed up between October 1995 and January 1999 at two community clinics in Entebbe, Uganda. Methods Systematic and standardized assessment of illness episodes to describe cryptococcal disease and death rates. Results Cryptococcal disease was diagnosed in 77 individuals (rate 40.4/1000 person-years) and was associated with 17% of all deaths (77 out of 444) in the cohort. Risk of infection was strongly associated with CD4 T cell counts < 200 × 106 cells/l(75 patients) and World Health Organization (WHO) clinical stage 3 and 4 (68 patients). Meningism was present infrequently on presentation (18%). Clinical findings had limited discriminatory diagnostic value. Serum cryptococcal antigen testing was the most sensitive and robust diagnostic test. Cryptococcal antigenaemia preceded symptoms by a median of 22 days (> 100 days in 11% of patients). Survival following diagnosis was poor (median survival 26 days; range 0–138). Conclusions Cryptococcal infection is an important contributor to mortality and suffering in HIV-infected Ugandans. Improvements in access to effective therapy of established disease are necessary. In addition, prevention strategies, in particular chemoprophylaxis, should be evaluated while awaiting the outcome of initiatives to make antiretroviral therapy more widely available.


The Lancet | 2003

Syndromic management of sexually-transmitted infections and behaviour change interventions on transmission of HIV-1 in rural Uganda: a community randomised trial

Anatoli Kamali; Maria A. Quigley; Jessica Nakiyingi; John Kinsman; J Kengeya-Kayondo; R Gopal; Amato Ojwiya; Peter Hughes; Lucy M. Carpenter; Jimmy Whitworth

BACKGROUND Treatment of sexually-transmitted infections (STIs) and behavioural interventions are the main methods to prevent HIV in developing countries. We aimed to assess the effect of these interventions on incidence of HIV-1 and other sexually-transmitted infections. METHODS We randomly allocated all adults living in 18 communities in rural Uganda to receive behavioural interventions alone (group A), behavioural and STI interventions (group B), or routine government health services and community development activities (group C). The primary outcome was HIV-1 incidence. Secondary outcomes were incidence of herpes simplex virus type 2 (HSV2) and active syphilis and prevalence of gonorrhoea, chlamydia, reported genital ulcers, reported genital discharge, and markers of behavioural change. Analysis was per protocol. FINDINGS Compared with group C, the incidence rate ratio of HIV-1 was 0.94 (0.60-1.45, p=0.72) in group A and 1.00 (0.63-1.58, p=0.98) in group B, and the prevalence ratio of use of condoms with last casual partner was 1.12 (95% CI 0.99-1.25) in group A and 1.27 (1.02-1.56) in group B. Incidence of HSV2 was lower in group A than in group C (incidence rate ratio 0.65, 0.53-0.80) and incidence of active syphilis for high rapid plasma reagent test titre and prevalence of gonorrhoea were both lower in group B than in group C (active syphilis incidence rate ratio, 0.52, 0.27-0.98; gonorrhoea prevalence ratio, 0.25, 0.10-0.64). INTERPRETATION The interventions we used were insufficient to reduce HIV-1 incidence in rural Uganda, where secular changes are occurring. More effective STI and behavioural interventions need to be developed for HIV control in mature epidemics.


AIDS | 1999

Rates of HIV-1 transmission within marriage in rural Uganda in relation to the HIV sero-status of the partners.

Lucy M. Carpenter; Anatoli Kamali; Anthony Ruberantwari; Samuel S. Malamba; Jimmy Whitworth

OBJECTIVE To assess the efficacy of transmission of HIV-1 within married couples in rural Uganda according to the sero-status of the partners. DESIGN Estimation of HIV incidence rates for 2200 adults in a population cohort followed for 7 years comparing male-to-female with female-to-male transmission and sero-discordant with concordant sero-negative couples. METHODS Each year, adults (over 12 years of age) resident in the study area were linked to their spouses if also censused as resident. The HIV sero-status was determined annually. RESULTS At baseline 7% of married adults were in sero-discordant marriages and in half of these the man was HIV-positive. Among those with HIV-positive spouses, the age-adjusted HIV incidence in women was twice that of men (rate ratio (RR) = 2.2 95% confidence interval (CI) 0.9-5.4) whereas, among those with HIV-negative spouses, the incidence in women was less than half that of men (RR = 0.4, 95% CI 0.2-0.8). The age-adjusted incidence among women with HIV-positive spouses was 105.8 times (95% CI 33.6-332.7) that of women with HIV-negative spouses, the equivalent ratio for men being 11.6 (95% CI 5.8-23.4). CONCLUSION Men are twice as likely as women to bring HIV infection into a marriage, presumably through extra-marital sexual behaviour. Within sero-discordant marriages women become infected twice as fast as men, probably because of increased biological susceptibility. Married adults, particularly women, with HIV-positive spouses are at very high risk of HIV infection. Married couples in this population should be encouraged to attend for HIV counselling together so that sero-discordant couples can be identified and advised accordingly.


The Journal of Infectious Diseases | 2002

Effect of human immunodeficiency virus (HIV) type 1 envelope subtypes A and D on disease progression in a large cohort of HIV-1-positive persons in Uganda.

Pontiano Kaleebu; Neil French; Cedric Mahe; David Yirrell; Christine Watera; Fred Lyagoba; Jessica Nakiyingi; Alleluiah Rutebemberwa; Dilys Morgan; Jonathan Weber; Charles F. Gilks; Jimmy Whitworth

The effect of human immunodeficiency virus (HIV) type 1 envelope subtypes A and D on disease progression was investigated in 1045 adults in Uganda. At enrollment and every 6 months, a clinical history, examination, and laboratory investigations that included CD4 cell counts were done. HIV-1 envelope subtype was assessed mainly by peptide serology supplemented by heteroduplex mobility assay and DNA sequencing. A multivariate analysis of survival was performed to assess the prognostic value of HIV-1 subtype on death. A marginal general linear model also determined the effect of subtype on CD4 cell count during follow-up. Subtype D was associated with faster progression to death (relative risk, 1.29; 95% confidence interval, 1.07-1.56; P=.009) and with a lower CD4 cell count during follow-up (P=.001), compared with subtype A, after adjusting for CD4 cell count at enrollment. In Africa, envelope subtype D is associated with faster disease progression, compared with subtype A.


AIDS | 2001

Increasing rates of malarial fever with deteriorating immune status in HIV-1-infected Ugandan adults.

Neil French; Jessica Nakiyingi; Eric Lugada; Christine Watera; Jimmy Whitworth; Charles F. Gilks

BackgroundFalciparum malaria and HIV-1 infection are two of the most important health problems facing sub-Saharan Africa. No convincing evidence of an association between symptomatic malaria and HIV-1 infection has been found. ObjectiveTo investigate the effect of HIV-associated immunosuppression on malarial fever rates. DesignAn observational cohort study in HIV-specific, primary healthcare clinics in Entebbe, Uganda, on 1371 HIV-1-infected adults participating in a randomized trial of 23-valent pneumococcal vaccine. MethodsCohort members underwent routine 6 monthly surveillance and had open clinic access when sick. Episodes of fever were assessed according to standardized protocols. Rates of malaria are described according to HIV immune status determined by CD4 T cell counts. ResultsIncidence rates of Plasmodium falciparum malarial fever showed a marked inverse relationship with CD4 T cell count; 140, 93 and 57 cases per 1000 pyo for CD4 T cell groups < 200, 200–499 and > 500 respectively, P < 0.001. Malarial fever definitions incorporating parasite density criteria (derived from asymptomatic surveillance) to correct for chance findings of fever and P. falciparum parasitaemia, did not affect the association of incidence rates with immunosuppression. ConclusionThese data support an interaction between symptomatic P. falciparum and HIV. Emphasis on mosquito avoidance measures should be an important component of education and counselling of HIV/AIDS patients in malaria-endemic areas, and suggests an additional HIV-related public health problem in Africa.


The Lancet | 2004

Transmission of HIV-1 infection in sub-Saharan Africa and effect of elimination of unsafe injections

George P. Schmid; Anne Buvé; Peter Mugyenyi; Geoff P. Garnett; Richard Hayes; Brian Williams; Jesus Maria Garcia Calleja; Kevin M. De Cock; Jimmy Whitworth; Saidi Kapiga; Peter D. Ghys; Catherine Hankins; Basia Zaba; Robert Heimer; J. Ties Boerma

During the past year, a group has argued that unsafe injections are a major if not the main mode of HIV-1 transmission in sub-Saharan Africa. We review the main arguments used to question the epidemiological interpretations on the lead role of unsafe sex in HIV-1 transmission, and conclude there is no compelling evidence that unsafe injections are a predominant mode of HIV-1 transmission in sub-Saharan Africa. Conversely, though there is a clear need to eliminate all unsafe injections, epidemiological evidence indicates that sexual transmission continues to be by far the major mode of spread of HIV-1 in the region. Increased efforts are needed to reduce sexual transmission of HIV-1.

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Dilys Morgan

Health Protection Agency

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Neil French

University of Liverpool

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Christine Watera

Uganda Virus Research Institute

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Jessica Nakiyingi

Uganda Virus Research Institute

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Pontiano Kaleebu

Uganda Virus Research Institute

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Robert Pool

University of Amsterdam

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Anatoli Kamali

Uganda Virus Research Institute

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Billy N. Mayanja

Uganda Virus Research Institute

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