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1.
Lancet Glob Health ; 4(5): e328-35, 2016 May.
Article in English | MEDLINE | ID: mdl-27102196

ABSTRACT

BACKGROUND: Evidence suggests that community-based interventions that promote improved home-based practices and care-seeking behaviour can have a large impact on maternal and child mortality in regions where rates are high. We aimed to assess whether an intervention package based on the WHO Integrated Management of Childhood Illness handbook and community mobilisation could reduce under-5 mortality in rural Guinea-Bissau, where the health service infrastructure is weak. METHODS: We did a non-masked cluster-randomised controlled trial (EPICS) in the districts of Tombali and Quinara in Guinea-Bissau. Clusters of rural villages were stratified by ethnicity and distance from a regional health centre, and randomly assigned (1:1) to intervention or control using a computerised random number generator. Women were eligible if they lived in one of the clusters at baseline survey prior to randomisation and if they were aged 15-49 years or were primary caregivers of children younger than 5 years. Their children were eligible if they were younger than 5 years or were liveborn after intervention services could be implemented on July 1, 2008. In villages receiving the intervention, community health clubs were established, community health workers were trained in case management, and traditional birth attendants were trained to care for pregnant women and newborn babies, and promote facility-based delivery. Registered nurses supervised community health workers and offered mobile clinic services. Health centres were not improved. The control group received usual services. The primary outcome was the proportion of children dying under age 5 years, and was analysed in all eligible children up to final visits to villages between Jan 1 and March 31, 2011. This trial is registered with ISRCTN, number ISRCTN52433336. FINDINGS: On Aug 30, 2007, we randomly assigned 146 clusters to intervention (73 clusters, 5669 women, and 4573 children) or control (73 clusters, 5840 women, and 4675 children). From randomisation until the end of the trial (last visit by June 30, 2011), the intervention clusters had 3093 livebirths and the control clusters had 3194. 6729 children in the intervention group and 6894 in the control group aged 0-5 years on July 1, 2008, or liveborn subsequently were analysed for mortality outcomes. 311 (4·6%) of 6729 children younger than 5 years died in the intervention group compared with 273 (4·0%) of 6894 in the control group (relative risk 1·16 [95% CI 0·99-1·37]). INTERPRETATION: Our package of community-based interventions did not reduce under-5 mortality in rural Guinea-Bissau. The short timeframe and other trial limitations might have affected our results. Community-based health promotion and basic first-line services in fragile contexts with weak secondary health service infrastructure might be insufficient to reduce child deaths. FUNDING: Effective Intervention.


Subject(s)
Community Health Workers/education , Health Promotion/methods , Infant Mortality , Midwifery/education , Patient Acceptance of Health Care , Adolescent , Adult , Child Mortality , Child, Preschool , Diarrhea/therapy , Female , Guinea-Bissau , Humans , Infant , Infant, Newborn , Malaria/drug therapy , Male , Middle Aged , Parturition , Pregnancy , Prenatal Care , Rural Population , Young Adult
2.
AIDS Res Hum Retroviruses ; 23(2): 204-15, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17331028

ABSTRACT

The human immunodeficiency virus type 1 (HIV-1) negative factor, or Nef, has a variety of functions that are important in viral pathogenesis. Sequence analysis has identified nef mutations that are linked to the rate of disease progression in adults and children infected with HIV-1 subtype B. Here we have sequenced and analyzed HIV-1 subtype C nef sequences from 34 children with rapid (RP) or slow progressing (SP) disease and identified polymorphisms associated with disease stage including motifs involved in specific pathogenic functions. Unlike subtype B, insertions and deletions in the N-terminal variable region were observed exclusively in SP children (8 out of 25). Strong positive selection pressures were found in sites of known functional importance among SP sequences, whereas RP had strong negative selection across the gene. A lineage analysis of selection pressures indicated weaker pressure across the nef gene in SP sequences bearing a deletion in region 8-12, suggesting this deletion has functional importance in vivo. Together these results suggest a differential adaptation of certain Nef functions related to disease progression, some of which may be attributable to immune-imposed pressures. These data broadly reflect previous studies on subtype B, corroborate the decreased cytopathicity of SP viruses, but also highlight potential subtype differences that require further investigation.


Subject(s)
Genes, nef/genetics , HIV Infections/genetics , HIV Infections/virology , HIV-1/genetics , Polymorphism, Genetic/genetics , Child , Child, Preschool , Cohort Studies , Disease Progression , HIV-1/classification , HIV-1/pathogenicity , Humans , Infant , Infant, Newborn , Molecular Sequence Data , Sequence Analysis, RNA
3.
J Med Virol ; 78(10): 1262-8, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16927278

ABSTRACT

V3 serotyping is a technique for determining HIV-1 genetic subtype based on the binding of antibodies from patient sera or plasma to synthetic V3 peptides derived from subtype consensus sequences. Variation in the performance of this assay has been attributed to V3 sequence heterogeneity, the degree of which varies with patient disease progression, virus co-receptor usage, and genetic subtype. This study assessed the performance of a competitive peptide enzyme immunoassay (cPEIA) in samples from HIV-1 subtype C infected patients with varying disease profiles, including those with syncytium (SI) and non-syncytium-inducing (NSI) viruses. Out of 90 sera tested, 94.4% reacted strongly against the subtype C peptide. There was no significant difference in assay sensitivity among samples from advanced AIDS patients in which humoral immune response may be lower, nor among SI viruses which carry changes in the V3 sequence. Four samples were found to be cross-reactive with other subtypes and one acutely infected patient sample was non-reactive due to low anti-gp120 antibody titers. A significantly higher number of samples showed secondary reactivity to subtype A, compared to other subtypes (P < 0.005). In conclusion, the assay was able to identify HIV-1 subtype C infection with a high level of sensitivity (94%) irrespective of the stage of disease and therefore provides a valuable resource for the large-scale epidemiological monitoring of the spread of HIV-1 subtypes in South Africa.


Subject(s)
HIV Envelope Protein gp120 , HIV Infections/virology , HIV-1/classification , Immunoenzyme Techniques/methods , Peptide Fragments , Reagent Kits, Diagnostic , Serotyping/methods , Cell Line, Transformed , Cohort Studies , Cross Reactions , Disease Progression , Female , Genetic Variation , Giant Cells , HIV Envelope Protein gp120/genetics , HIV Infections/diagnosis , HIV-1/physiology , Humans , Infant , Molecular Sequence Data , Peptide Fragments/genetics , Sensitivity and Specificity , South Africa
4.
Infect Genet Evol ; 5(3): 199-208, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15737910

ABSTRACT

The human immunodeficiency virus (HIV) pandemic continues to grow at an alarming rate, with a further 5 million new infections in 2003. Some 3.5 million of these were in sub-Saharan Africa, where approximately 70% of the world's HIV-positive population resides. In contrast, the spread of HIV in high-income countries has slowed since its discovery in the 1980s, and in regions such as Western Europe prevalence has decreased. Here, we employ coalescent methods to compare the epidemic growth rates of two subtypes of HIV-1 with differing epidemiological profiles: subtype C, which is dominant in sub-Saharan Africa and associated with heterosexual transmission, and subtype B, the main cause of AIDS in Western Europe and North America, and which was primarily transmitted through homosexual sex and injecting drug use. We show that although both subtypes emerged at approximately the same time ( approximately 1960), they have widely differing patterns of exponential population growth. At its current growth rate the epidemic of subtype C in sub-Saharan Africa is doubling every 2.4 years, which is approximately half the rate observed during the early stages of the subtype B epidemic in Western Europe and North America. However, the subtype C growth rate is still 5-10 times greater than that estimated for the blood-borne hepatitis C virus, supporting the hypothesis that sexual transmission has been primarily responsible for the HIV epidemic in sub-Saharan Africa.


Subject(s)
HIV Infections/epidemiology , HIV-1/physiology , Population Dynamics , Acquired Immunodeficiency Syndrome/transmission , Africa South of the Sahara/epidemiology , Biological Evolution , Disease Outbreaks , Disease Transmission, Infectious , Europe/epidemiology , Gene Products, env/genetics , Gene Products, gag/genetics , Genetic Variation , HIV Infections/transmission , HIV Infections/virology , HIV Reverse Transcriptase/genetics , HIV-1/genetics , HIV-1/pathogenicity , Hepatitis C/epidemiology , Heterosexuality , Humans , Likelihood Functions , North America/epidemiology
6.
Exp Parasitol ; 101(2-3): 121-8, 2002.
Article in English | MEDLINE | ID: mdl-12427466

ABSTRACT

Rosetting is a property of many malaria parasite species that has been linked to virulence in the major species infecting humans, Plasmodium falciparum. Here, the basic properties of rosettes in the rodent malaria laboratory model, P. chabaudi, were studied with a view to future studies on the role of rosetting in malaria parasite virulence and transmission. Rosetting occurred in 14 out of the 15 P. chabaudi clones studied, varied consistently between clones, and ranged between 9 and 37% at full parasite maturity. Rosetting frequency markedly declined after the mouse reached peak parasitemia, possibly due to host immunity. Consistent with P. falciparum and P. vivax, rosettes in P. chabaudi were disrupted by treatment with trypsin and EDTA. However, P. chabaudi rosettes were insensitive to sulfated glycoconjugates (heparin, heparan sulfate and fucoidan). The molecular basis of rosetting in P. chabaudi is unknown at present, but the results suggest that the molecules involved may differ from those in human-infecting species.


Subject(s)
Malaria/parasitology , Plasmodium chabaudi/pathogenicity , Animals , Anticoagulants/pharmacology , Disease Models, Animal , Edetic Acid/pharmacology , Erythrocytes/cytology , Erythrocytes/parasitology , Glycoconjugates/pharmacology , Malaria/immunology , Male , Mice , Mice, Inbred C57BL , Parasitemia/immunology , Parasitemia/parasitology , Plasmodium chabaudi/drug effects , Plasmodium chabaudi/immunology , Rosette Formation , Serial Passage , Trypsin/pharmacology , Virulence
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