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Objective Under Millennium Development Goal 4, countries are required to reduce child mortality by two-thirds between 1990 and 2015. In countries with generalized epidemics of human immunodeficiency virus (HIV) infection, standard statistics based on fertility history may misrepresent progress towards this target owing to the correlation between deaths among mothers and early childhood deaths from acquired immunodeficiency syndrome. Methods To empirically estimate this bias, child mortality data and fertility history, including births to deceased women, were collected through prospective household surveys in eastern Zimbabwe during 1998-2005. A mathematical model was then used to investigate the determinants and temporal dynamics of the bias, first in Zimbabwe and then in other countries with different background mortality rates and HIV-related epidemic profiles. Findings According to the empirical data, standard cross-sectional survey statistics underestimated true infant and under-5 mortality by 6.7% and 9.8%, respectively. These estimates were in agreement with the output from the model, in which the bias varied according to the magnitude and stage of the epidemic of HIV infection and background mortality rates. The bias was greater the longer the period elapsed before the survey and in later stages of the epidemic. Bias could substantially distort the measured effect of interventions to reduce non-HIV-related mortality and of programmes to prevent mother-to-child transmission, especially when trends are based on data from a single survey. Conclusion The correlation between the HIV-related deaths of mothers and their children can bias survey estimates of early child mortality. A mathematical model with a user-friendly interface is available to correct for this bias when measuring progress towards Millennium Development Goal 4 in countries with generalized epidemics of HIV infection. Objectif En vertu de l'Objectif 4 du Millenaire pour le developpement, les pays doivent reduire la mortalite infantile de deux tiers entre 1990 et 2015. Dans les pays enregistrant une epidemie generalisee du virus de I'immunodeficience humaine (VIH), les statistiques standard basees sur I'historique de la fertilite peuvent presenter de maniere inexacte le progres en ce sens, de par la correlation entre les deces des meres et les deces des nouveau-nes lies au syndrome d'immunodeficience acquise. Methodes Pour evaluer d'un point de vue empirique cette erreur, les donnees de mortalite infantile et l'historique de la fertilite, y compris les naissances chez des meres decedees, ont ete recueillis en realisant des enquetes de menage prospectives dans l'Est Zimbabwe entre 1998 et 2005. Un modele mathematique a ensuite utilise pour examiner les determinants et la dynamique temporale de l'influence, d'abord au Zimbabwe, puis dans d'autres pays presentant des taux de mortalite et des profils epidemiques lies au VIH differents. Resultats D'apres les donnees empiriques, les statistiques des enquetes croisees standard ont sous-estime la vraie mortalite chez les nourrissons et les enfants de moins de 5 ans, de 6,7% et de 9,8% respectivement. Ces evaluations etaient en accord avec les resultats du modele dans lequel l'influence variait en fonction de I'ampleur et du stade de l'epidemie de VIH et des taux de mortalite. L'influence etait plus importante sur une periode plus longue avant l'enquete et a des stades ulterieurs de l'epidemie. Cette influence peut considerablement deformer l'effet mesure des interventions en vue de reduire la mortalite non lice au VIH et des programmes de prevention de la transmission mere-enfant, en particulier lorsque les tendances reposent sur les donnees d'une seule enquete. Conclusion La correlation entre les deces de meres et de leurs enfants lies au VIH peut influencer les evaluations des enquetes sur la mortalite des nouveau-nes. Un modele mathematique dote d'une interface conviviale est disponible pour corriger cette influence lors de la mesure des progres vers l'Objectif 4 du Millenaire pour le developpement dans les pays presentant une epidemie generalisee d'infection au VIH. Objetivo Segun el Objetivo de Desarrollo del Milenio numero 4, los paises deben reducir la mortalidad infantil en dos tercios entre 1990 y 2015. En los paises con epidemia generalizada de infeccien porel virus de inmunodeficiencia humana (VIH), los datos estadisticos estandar basados en el historial de embarazos pueden dar una idea equivocada del avance hacia la consecucien de este objetivo como consecuencia de la correlacien entre los fallecimientos de las madres y los fallecimientos en la primera infancia debidos al sindrome de inmunodeficiencia adquirida. Metodos Para calcular empiricamente este sesgo, se recopilaron datos de mortalidad infantil y el historial de embarazos, incluyendo nacimientos en mujeres fallecidas, mediante encuestas prospectivas por hogares realizadas en Zimbabwe oriental durante 1998-2005. Luego, se utilize un modelo matematico para investigar los factores determinantes y la dinamica temporal del sesgo, primero en Zimbabwe y, despues, en otros paises con tasas de mortalidad de fondo diferentes y perfiles epidemicos relacionados con el VIH. Resultados Segun los datos empiricos, los datos estadisticos de las encuestas transversales estandar subestimaron la verdadera mortalidad en lactantes y ninos menores de b anos en un 6,7% y un 9,8%, respectivamente. Estos calculos concordaban con los resultados del modelo, en el que el sesgo variaba en funcion de la magnitud y el estadio de la epidemia de la infeccion por VIH y las tasas de mortalidad de fondo. El sesgo era mayor cuanto mas tiempo habia transcurrido antes de la encuesta yen los ultimos estadios de la epidemia. El sesgo podia distorsionar sustancialmente el efecto medido de las intervenciones para reducir la mortalidad no relacionada con el VIH y de los programas para prevenir la transmision de la madre al nino, especiaimente cuando las tendencias se basan en datos de una enica encuesta. Conclusion La correlacion entre los fallecimientos relacionados con el VIH de las madres y de sus hijos puede ocasionar un sesgo en las estimaciones de la mortalidad en la primera infancia obtenidas a partir de las encuestas. Esta disponible un modelo matematico con una interfaz facil de usar para corregir este sesgo cuando se mide el progreso para la consecucion del Objetivo de Desarrollo del Milenio nemero 4 en paises con epidemia generalizada de infeccion por VIH., Introduction Millennium Development Goal 4 (MDG4) calls for countries to reduce child mortality rates by two-thirds between 1990 and 2015. (1,2) There is concern that progress towards meeting this target [...]

Objective To assess the diagnostic value of provider-initiated symptom screening for tuberculosis (TB) and how HIV status affects it. Methods We performed a secondary analysis of randomly selected participants in a community-based TB-HIV prevalence survey in Harare, Zimbabwe. All completed a five-symptom questionnaire and underwent sputum TB culture and HIV testing. We calculated the sensitivity, specificity, and positive and negative predictive values of various symptoms and used regression analysis to investigate the relationship between symptoms and TB disease. Findings We found one or more symptoms of TB in 21.2% of 1858 HIV-positive (HIV+) and 9.9% of 7121 HIV-negative (HIV-) participants (P < 0 .001). TB was subsequently diagnosed in 48 HIV+ and 31 HIV-participants. TB was asymptomatic in 18 culture-positive individuals, 8 of whom (4 in each HIV status group) had positive sputum smears. Cough of any duration, weight loss and, for HIV+ participants only, drenching night sweats were independent predictors of TB. In HIV+ participants, cough of ≥ 2 weeks' duration, any symptom and a positive sputum culture had sensitivities of 48%, 81% and 65%, respectively; in HIV--participants, the sensitivities were 45%, 71% and 74%; respectively. Symptoms had a similar sensitivity and specificity in HIV+ and HIV- participants, but in HIV+ participants they had a higher positive and a lower negative predictive value. Conclusion Even smear-positive TB may be missed by provider-initiated symptom screening, especially in HIV+ individuals. Symptom screening is useful for ruling out TB, but better TB diagnostics are urgently needed for resource-poor settings. Objectif Evaluer la valeur diagnostique de la recherche des symptomes de la tuberculose (TB) a l'initiative du prestateur et comment le statut VIH influe sur cette valeur diagnostique. Methodes Nous avons realise une analyse secondaire sur des participants selectionnes au hasard parmi les sujets d'une enquete en communaute concernant la prevalence de la co-infection TB-VIH, menee a Harare, au Zimbabwe. Tous les participants ont repondu a un questionnaire portant sur cinq symptomes et ont fait l'objet d'une culture d'expectorations pour rechercher la tuberculose et d'un depistage du VIH. Nous avons calcule la sensibilite, la specificite et les valeurs predictives positive et negative des differents symptomes et etudie la relation entre ces symptomes et la tuberculose maladie en utilisant l'analyse par regression. Resultats Nous avons releve un ou plusieurs symptomes de la tuberculose chez 21,2 % des 1858 participants positifs pour le VIH (VIH+) et chez 9,9 % des 7121 participants negatifs pour ce virus (p < 0,001). La tuberculose a ensuite ete diagnostiquee chez 48 sujets VIH+ et chez 31 sujets VIH-. Cette maladie etait presente de maniere asymptomatique chez 18 individus positifs a la culture, dont 8 (4 pour chacun des statuts VIH) donnaient ales frottis d'expectorations positifs. La toux, quelle que soit sa duree, la perte de poids et pour les participants VIH+ uniquement, la sudation nocturne, constituaient des facteurs predictifs independants de la tuberculose. Chez les participants VIH+, la presence de toux pendant 2 semaines ou plus, chacun des symptomes et l'obtention d'une culture d'expectorations positive presentaient respectivement une sensibilite de 48, 81 et 65 %. Chez les participants VIH-, les sensibilites correspondantes valaient respectivement 45, 71 et 74 %. Les symptomes fournissaient donc une sensibilite et une specificite similaires chez les deux types de participants, mais chez les sujets VIH+, ils avaient une valeur predictive positive plus elevee et une valeur predictive negative plus faible. Conclusion La recherche des symptomes a l'initiative du prestateur peut laisser passer meme ales cas de tuberculose frottis positifs, en particulier chez les individus seropositifs pour le VIH. Le depistage sur la base des symptomes est utile pour exclure la tuberculose, mais les pays demunis ont besoin d'urgence d'un meilleur outil pour diagnostiquer cette maladie. Objetivo Determinar el valor diagnostico del cribado de sintomas de tuberculosis a instancias del profesional, asi como la influencia de la serologia VIH en dicho cribado. Metodos Realizamos un analisis secundario a partir de participantes seleccionados aleatoriamente en una encuesta comunitaria de prevalencia de la coinfeccion tuberculosis-VIH realizada en Harare, Zimbabwe. Todos ellos respondieron a un cuestionario sobre cinco sintomas y se sometieron a pruebas del VIH y de cultivo de esputo para la tuberculosis. Calculamos la sensibilidad, la especificidad y los valores predictivos positivo y negativo de Ios diversos sintomas y realizamos un analisis de regresion para investigar la relacion entre Ios sintomas y la tuberculosis. Resultados Detectamos uno o mas sintomas de tuberculosis en el 21,2% de 1858 pacientes VIH-positivos (VIH+) y el 9,9% de 7121 participantes VIH-negativos (VIH-) (p < 0,001). Posteriormente se diagnostico tuberculosis en 48 participantes VIH+ y 31 participantes VIH-. Sufrian tuberculosis asintomatica 18 personas con cultivo positivo, 8 de las cuales (4 en cada grupo serologico) presentaron esputo positivo. La tos de cualquier duracion, la perdida de peso y, solo en el caso de Ios participantes VIH+, la presencia de sudores nocturnos, fueron factores predictivos independientes de la tuberculosis. En las personas VIH+, la tos de mas de 2 semanas de duracion, la presencia de cualquiera de los sintomas y un cultivo de esputo positivo tuvieron una sensibilidad del 48%, 81% y 65%, respectivamente; entre los participantes VIH-, la sensibilidad fue del 45%, 71% y 74%, respectivamente. Los sintomas presentaron una sensibilidad y especificidad similares en Ios pacientes VIH+ y VIH-, pero en los primeros tenian un mayor valor predictivo positivo y un menor valor predictivo negativo. Conclusion Incluso la tuberculosis con baciloscopia positiva puede pasar desapercibida en el cribado de Ios sintomas realizado a instancias del profesional, especialmente en las personas VIH+. El cribado de los sintomas es util para descartar la tuberculosis, pero se necesitan urgentemente mejores medios de diagnostico de esta enfermedad para Ios entornos con recursos escasos., Introduction Symptom questionnaires provide a quick, cheap and convenient way to identify individuals at a high risk of tuberculosis (TB) disease, termed TB suspects, who then need investigation with more [...]

ABSTRACT Background HIV-1 control in sub-Saharan Africa requires cost-effective and sustainable programmes that promote behaviour change and reduce cofactor sexually transmitted infections (STIs) at the population and individual levels. Methods [...]

ABSTRACT Background HIV counselling and testing is a key component of both HIV care and HIV prevention, but uptake is currently low. We investigated the impact of rapid HIV testing [...]

Certain intravaginal practices used by some prostitutes in Zimbabwe do not appear to injure the vaginal mucosa and thereby increase the risk of HIV infection. These practices include inserting objects into the vagina, douching, using substances to tighten the vagina, or engaging in dry sex.

Abstract Background In highly populated African urban areas where access to clean water is a challenge, water source contamination is one of the most cited risk factors in a cholera epidemic. During the rainy season, where there is either no sewage disposal or working sewer system, runoff of rains follows the slopes and gets into the lower parts of towns where shallow wells could easily become contaminated by excretes. In cholera endemic areas, spatial information about topographical elevation could help to guide preventive interventions. This study aims to analyze the association between topographic elevation and the distribution of cholera cases in Harare during the cholera epidemic in 2008 and 2009. Methods We developed an ecological study using secondary data. First, we described attack rates by suburb and then calculated rate ratios using whole Harare as reference. We illustrated the average elevation and cholera cases by suburbs using geographical information. Finally, we estimated a generalized linear mixed model (under the assumption of a Poisson distribution) with an Empirical Bayesian approach to model the relation between the risk of cholera and the elevation in meters in Harare. We used a random intercept to allow for spatial correlation of neighboring suburbs. Results This study identifies a spatial pattern of the distribution of cholera cases in the Harare epidemic, characterized by a lower cholera risk in the highest elevation suburbs of Harare. The generalized linear mixed model showed that for each 100 meters of increase in the topographical elevation, the cholera risk was 30% lower with a rate ratio of 0.70 (95% confidence interval=0.66-0.76). Sensitivity analysis confirmed the risk reduction with an overall estimate of the rate ratio between 20% and 40%. Conclusion This study highlights the importance of considering topographical elevation as a geographical and environmental risk factor in order to plan cholera preventive activities linked with water and sanitation in endemic areas. Furthermore, elevation information, among other risk factors, could help to spatially orientate cholera control interventions during an epidemic.