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Reliable population-based prevalence data are essential for planning, monitoring and evaluating trachoma control programmes and understanding the scale of the problem, yet they are not currently available for 22 out of 56 trachoma-endemic countries. Three survey methods have been advocated for trachoma: cluster random sampling (CRS); trachoma rapid assessment (TRA); and acceptance sampling trachoma rapid assessment (ASTRA). Our review highlights the benefits of CRS being simple, efficient, repeatable and giving population-based prevalence estimates of all signs of trachoma. There are limitations to TRA, which include: non-representative sampling; does not estimate prevalence; and lacks consistency and accuracy. ASTRA advocates small sample sizes but it is relatively complex, may result in imprecise prevalence estimates and does not estimate cicatriciat signs of trachoma. We conclude that CRS should therefore remain the "gold" standard for trachoma surveys. However, among the CRS surveys reviewed, we also found several methodological deficiencies of sample-size calculations, standardization of trachoma graders, reporting of confidence intervals of prevalence estimates, variability of age groups for presentation of age-specific prevalence, and lack of estimation of district prevalence estimates. Properly conducted surveys will be crucial if the objective of global elimination of blinding trachoma is to be charted and realized. Harmonization of survey methods will enhance the conduct and comparability of trachoma surveys needed for reliable mapping of prevalence within endemic countries. Consistent with WHO recommendations, we advocate for continued use of CRS as the survey design of choice for trachoma control programmes and propose ways of improving future surveys based on this method. Il est essentiel de disposer de donnees de prevalence en population fiables pour planifier, surveiller et evaluer les programmes de lutte contre le trachome et apprehender l'ampleur du probleme. Cependant, sur les 56 pays ou cette maladie est endemique, 22 ne disposent pas de telles donnees. Trois methodes d'enquete ont ete preconisees pour le trachome :le sondage aleatoire en grappes (CRS) ; I'appreciation rapide du trachome (ART) et l'echantillonnage par lots pour l'assurance de la qualite (ASTRA). Notre etude fait ressortir les avantages de la methode CRS, a savoir sa simplicite, son efficacite, sa reproductibilite et sa capacite a fournir des estimations de la prevalence en population de tous les signes du trachome. La methode ART comporte des limitations :en particulier, elle utilise des echantillons non representatifs, ne fournit pas d'estimation de la prevalence et manque de coherence et de precision. La methode ASTRA ne requiert que des echantillons de petite taille, mais presente une certaine complexite, peut conduire a des estimations imprecises de la prevalence et n'evalue pas les signes cicatriciels du trachome. Nous en concluons que la methode CSR doit rester la methode de reference pour les enquetes sur cette maladie. Cependant, parmi les enquetes utilisant la methode CRS examinees, nous avons trouve plusieurs defauts methodologiques dans le calcul de la taille des echantillons, la standardisation des grades du trachome, l'indication des intervalies de confiance pour les estimations de la prevalence, la variabilite des tranches d'ages pour la presentation de la prevalence par age et le manque d'estimations de la prevalence a l'echelle du district. Il est indispensable que les enquetes soient correctement menees si l'on veut se donner comme objectif l'elimination mondiale du trachome et realiser cet objectif. Une harmonisation des methodes d'enquete permettrait d'ameliorer la conduite et la comparabilite des enquetes sur le trachome necessaires a une cartographie fiable de la prevalence de cette maladie dans les pays d'endemie. En accord avec les recommandations de l'OMS, nous preconisons de poursuivre l'application de la CRS comme methode d'enquete de choix dans les programmes de lutte contre le trachome et nous proposons des moyens pour ameliorer les futures enquetes reposant sur cette methode. La obtencion de datos poblacionales fiables sobre la prevalencia es fundamental para planificar, vigilar y evaluar los programas de control del tracoma y determinar la magnitud del problema, pero aun no se dispone de tales datos para 22 de los 56 paises con tracoma endemico. Se han propuesto tres metodos para las encuestas sobre el tracoma: muestreo aleatorio por conglomerados (MAC); evaluacion rapida del tracoma (ERT); y evaluacion rapida del tracoma mediante muestreo de aceptacion (ERTMA). Nuestra revision destaca las ventajas del MAC, por tratarse de un metodo sencillo, eficiente, reproducible, y que arroja estimaciones poblacionales de la prevalencia de todos los signos de tracoma. La ERT presenta algunas limitaciones, entre ellas que el muestreo no es representativo, que no estima la prevalencia, y que adolece de falta de coherencia y de exactitud. La ERTMA propone tamanos de muestra pequenos pero es relativamente compleja, puede dar lugar a estimaciones de la prevalencia imprecisas y no estima los signos cicatrizales del tracoma. Nuestra conclusion es que el MAC deberia seguir siendo por tanto el patron de referencia en las encuestas sobre el tracoma. Sin embargo, entre las encuestas revisadas basadas en el MAC hemos hallado tambien varias deficiencias metodologicas en los calculos del tamano de la muestra, la normalizacion de los grados de tracoma, la notificacion de los intervalos de confianza de las prevalencias estimadas, la variabilidad de los grupos de edad en las presentaciones de la prevalencia por edades y la falta de estimaciones de la prevalencia por distritos. Es fundamental disponer de unas encuestas rigurosamente realizadas si se desea vigilar los progresos y alcanzar el objetivo de la eliminacion mundial del tracoma causante de ceguera. La armonizacion de los metodos de encuesta facilitara la realizacion y comparabilidad de las encuestas al respecto que es necesario realizar para mapear fiablemente la prevalencia de la enfermedad en los paises endemicos. En coherencia con las recomendaciones de la OMS, proponemos que se siga usando el MAC como diseno encuestal de eleccion en los programas de control del tracoma y sugerimos alternativas para mejorar las futuras encuestas basadas en ese metodo., Introduction Trachoma surveys are essential in that they provide the fundamental data for quantifying disease burden that facilitates planning, implementation, monitoring and evaluation of trachoma control programmes. Communities with trachoma [...]

An outbreak of avian influenza (H7N3) among poultry resulted in laboratory-confirmed disease in 1 of 103 exposed persons. Incomplete use of personal protective equipment (PPE) was associated with conjunctivitis and [...]

ABSTRACT Background Trachoma is a leading cause of preventable blindness. Reports from eye surgery camps and anecdotal data indicated that blinding trachoma is a serious cause of visual impairment in [...]

ABSTRACT Background Blindness and low vision are thought to be common in southern Sudan. However, the magnitude and geographical distribution are largely unknown. We aimed to estimate the prevalence of [...]

Objective Limited surveys and anecdotal data indicate that trachoma is endemic in the states of Eastern Equatoria and Upper Nile in southern Sudan. However, its magnitude and geographical distribution are largely unknown. We conducted surveys to ascertain the prevalence and geographical distribution of trachoma, and to identify targets for control interventions. Methods Population-based cross-sectional surveys were conducted in nine sites in southern Sudan between September 2001 and June 2004. Two-stage random cluster sampling with probability proportional to size was used to select the sample. Trachoma grading was done using the WHO simplified grading system. Findings A total of 17 016 persons were examined, a response rate of 86.1% of the enumerated population. Prevalence of signs of active trachoma in children aged 1-9 years was: TF = 53.7% (95% confidence interval (CI) = 52.1-55.3); TI = 42.7% (95% CI = 41.2-44.2); TF and/or TI = 64.1% (95% CI = 62.5-65.5). Prevalence of trichiasis (TT) in children aged less than 15 years was 1.2% (95% CI = 0.9-1.4), while TT prevalence in persons aged 15 years and above was 9.2% (95% CI = 8.6-9.9). Women were more likely to have trichiasis compared to men (odds ratio (OR) = 1.57; 95% CI = 1.34-1.84). Tentative extrapolation to the states of Eastern Equatoria and Upper Nile estimates that there is a backlog of 178 250 (lower and upper bounds = 156 027-205 995) persons requiring surgery and the entire population, estimated to be over 3.9 million, is in need of the SAFE strategy to control blinding trachoma. Conclusions Trachoma is a public health problem in all nine of the study sites surveyed. The unusually high prevalence of active trachoma and TT in children points to the severity of the problem. There is urgent need to implement trachoma control interventions in trachoma endemic regions of southern Sudan. Keywords Trachoma/epidemiology; Eyelid diseases/epidemiology; Sudan (source: MeSH, NLM). Objectif Des enquetes limitees et des donnees anecdotiques indiquent que le trachome est endemique dans les Etats de l'Equatoria oriental et du Nil superieur au Soudan meridional. Toutefois, l'ampleur du phenomene et sa distribution geographique sont largement meconnues. Des enquetes ont ete menees pour determiner la prevalence et la distribution geographique du trachome et identifier les cibles des interventions a mettre en oeuvre contre cette maladie. Methodes Des enquetes transversales en population ont ete realisees en neuf sites du Soudan meridional, entre septembre 2001 et juin 2004. La selection des echantillons s'est effectuee par sondage en grappes a deux degres, avec une probabilite proportionnelle a la taille de la population. Le codage de la maladie a ete realise selon le systeme OMS simplifie de codage du trachome. Resultats Au total 17 016 personnes ont ete examinees, ce qui correspondait a un taux de reponses de 86,1% pour l'ensemble de la population recensee. La prevalence des signes du trachome evolutif chez les enfants de 1 a 9 ans s'etablissait de la maniere suivante : trachome inflammatoire folliculaire (TF) = 53,7 % (intervalle de confiance a 95 % (IC) = 52,1-55,3) ; trachome inflammatoire intense (TI) = 42,7 % (IC a 95 % = 41,2-44,2) ; TF et/ou TI = 64,1% (IC a 95 % = 62,5-65,5). Chez l'enfant de moins de 15 ans, la prevalence du trichiasis (TT) etait de 1,2 % (IC a 95 % = 0,9-1,4), alors que chez les personnes de 15 ans et plus, elle atteignait 9,2 % (IC a 95 % = 8,6-9,9). Les femmes etaient plus sujettes au trichiasis que les hommes [odds ratio (OR) = 1,57; IC a 95 % = 1,34-1,84]. Les tentatives pour extrapoler ces chiffres aux Etats de l'Equatoria oriental et du Nil superieur conduisent a une estimation de 178 250 (limites inferieure et superieure = 156 027 et 205 995) pour le nombre de personnes en attente de soins chirurgicaux. D'autre part, l'ensemble de la population, evaluee a plus de 3,9 millions d'habitants, a besoin de la strategie CHANCE, destinee a indiquer le trachome cecitant. Conclusion Le trachome pose un probleme de sante publique pour l'ensemble des neuf sites ayant servi de cadre a l'enquete. La prevalence inhabituellement elevee du trachome evolutif et du TT chez I'enfant denote bien la gravite du probleme. Il est urgent de metre en oeuvre des interventions de lutte contre le trachome dans les regions du Soudan meridional ou cette maladie est endemique. Mots cles Trachome/epidemiologie; Paupiere, Maladies/epidemiologie; Soudan (source: MeSH, INSERM). Objetivo Segun algunos estudios limitados y diversos datos no comprobados, el tracoma es endemico en las regiones de Equatoria oriental y Alto Nilo del sur del Sudan. Sin embargo, se desconocen en gran medida la magnitud del problema y la distribucion geografica de la enfermedad. Realizamos estudios para determinar la prevalencia y la distribucion geografica del tracoma, asi como para identificar objetivos para las intervenciones de control. Metodos Entre septiembre de 2001 y junio de 2004 se llevaron a cabo estudios transversales basados en la poblacion en nueve sitios del sur del Sudan. Se utilizo un metodo de muestreo aleatorio por conglomerados en dos etapas con probabilidad proporcional al tamano. La tipificacion del tracoma se realizo conforme al sistema de clasificacion simplificado de la OMS. Resultados Se exploro a un total de 17 016 personas, con una tasa de respuesta del 86,1% de la poblacion considerada. La prevalencia de signos de tracoma activo en los ninos de 1 a 9 anos era la siguiente: TF (inflamacion folicular) = 53,7% (intervalo de confianza (IC) del 95% = 52,1- 55,3); TI (inflamacion intensa) = 42,7% (IC95% = 41,2 - 44,2); TF y/o TI = 64,1% (IC95% = 62,5 - 65,5). La prevalencia de triquiasis TT) entre los ninos de menos de 15 anos era del 1,2% (IC95% = 0,9 - 1,4), mientras que la prevalencia de TT en las personas de 15 anos y mas era del 9,2%. (IC95% = 8,6 - 9,9). Las mujeres tenian mas probabilidades que los hombres de sufrir triquiasis (razon de posibilidades (OR) = 1,57; IC95% = 1,34 - 1,84). La extrapolacion provisional a las regiones de Equatoria oriental y Alto Nilo arroja un cumulo estimado de 178 250 personas (limites inferior y superior = 156 027 - 205 995) necesitadas de intervencion quirurgica; si se desea controlar el tracoma causante de ceguera, la estrategia SAFE deberia abarcar a toda la poblacion, estimada en mas de 3,9 millones de personas. Conclusion El tracoma constituye un problema de salud publica en los nueve sitios estudiados. La prevalencia excepcionalmente alta de tracoma activo y TT en la poblacion infantil demuestra la gravedad del problema. Hay que aplicar urgentemente intervenciones de control del tracoma en las regiones del sur del Sudan donde la enfermedad es endemica. Palabras clave Tracoma/epidemiologia; Enfermedades de los parpados/epidemiologia; Sudan (fuente: DeCS, BIREME). Bulletin of the World Health Organization 2005;83:904-912. [TEXT NOT REPRODUCIBLE IN ASCII.], Voir page 910 le resume en francais. En la pagina 911 figura un resumen en espanol. Introduction Trachoma, caused by ocular infection with Chlamydia trachomatis, is the most common infectious [...]

The incidence of sporadic cryptosporidiosis among 106,000 residents of 2 local government districts in northwest England before and after installation of membrane filtration of public water supplies was compared to [...]

Healthcare-associated outbreaks of gastroenteritis are an increasingly recognized problem, but detailed knowledge of the epidemiology of these events is lacking. We actively monitored three hospital systems in England for outbreaks [...]

Risk factors for sporadic cryptosporidiosis were determined in 152 patients and 466 unmatched controls who resided in two local government districts in North Cumbria, North West England, from March 1, [...]

To gain understanding of surveillance and epidemiology of viral gastroenteritis outbreaks in Europe, we compiled data from 10 surveillance systems in the Foodborne Viruses in Europe network. Established surveillance systems [...]

In the period 1992-2000, the Public Health Laboratory Service Communicable Disease Surveillance Centre collected standardized epidemiologic data on 1,877 general outbreaks of Norovirus (formerly "Norwalk-like virus") infection in England and [...]

During the 2001 epidemic of foot and mouth disease (FMD) in livestock in England and Wales, we discovered a corresponding decrease in laboratory reports of cryptosporidiosis in humans. Using a [...]

The Public Health Laboratory Service receives antibiotic susceptibility data for bacteria from bloodstream infections from most hospitals in England and Wales. These data were used to ascertain resistance trends to [...]

Abstract Background We investigated vision status associated with trachomatous trichiasis (TT) and explored age-sex patterns of low vision and blindness associated with trichiasis in Mankien district of southern Sudan where trachoma prevention and trichiasis surgery were absent. Methods A population based survey was undertaken and eligible persons underwent eye examination. Visual acuity (VA) was tested using Snellen E chart and persons with TT identified. Vision status was defined using the WHO categories of visual impairment based on presenting VA: normal vision (VA ≥ 6/18 in better eye); low vision (VA < 6/18 but ≥ 3/60 in better eye); and blindness (VA < 3/60 in better eye). An ordinal logistic regression model was fitted and age/sex specific distribution of vision status predicted. Results Overall 341/3,567 persons examined had any TT. Analysis was based on 319 persons, 22 persons were excluded: 20 had both TT and cataract; and 2 had missing VA data. Of the 319 persons: 158(49.5%) had trichiasis-related corneal opacity (CO); bilateral TT and bilateral CO were found in 251(78.7%) and 110 (34.5%), respectively; 146 (45.8%) had low vision or blindness; the ratio of low vision to blindness was 3.2:1; and no sex differences were observed. In our model the predicted distribution of vision status was: normal vision, 53.9% (95% CI 50.9–56.9); low vision, 35.3% (95% CI 33.3–37.2); and blindness, 10.9% (95% CI 9.7–12.0). Conclusion We have reported severe trichiasis and high prevalence of vision loss among persons with trichiasis. Our survey showed that almost 1 in 20 of the entire population suffered low vision or blindness associated with trachoma. The need for trichiasis surgery, trachoma prevention services, and rehabilitation of the blind is acute.

Abstract Background Noroviruses are highly infectious pathogens that cause gastroenteritis in the community and in semi-closed institutions such as hospitals. During outbreaks, multiple units within a hospital are often affected, and a major question for control programs is: are the affected units part of the same outbreak or are they unrelated transmission events? In practice, investigators often assume a transmission link based on epidemiological observations, rather than a systematic approach to tracing transmission. Here, we present a combined molecular and statistical method for assessing: 1) whether observed clusters provide evidence of local transmission and 2) the probability that anecdotally|linked outbreaks truly shared a transmission event. Methods 76 healthcare associated outbreaks were observed in an active and prospective surveillance scheme of 15 hospitals in the county of Avon, England from April 2002 to March 2003. Viral RNA from 64 out of 76 specimens from distinct outbreaks was amplified by reverse transcription-PCR and was sequenced in the polymerase (ORF 1) and capsid (ORF 2) regions. The genetic diversity, at the nucleotide level, was analysed in relation to the epidemiological patterns. Results Two out of four genetic and epidemiological clusters of outbreaks were unlikely to have occurred by chance alone, thus suggesting local transmission. There was anecdotal epidemiological evidence of a transmission link among 5 outbreaks pairs. By combining this epidemiological observation with viral sequence data, the evidence of a link remained convincing in 3 of these pairs. These results are sensitive to prior beliefs of the strength of epidemiological evidence especially when the outbreak strains are common in the background population. Conclusion The evidence suggests that transmission between hospitals units does occur. Using the proposed criteria, certain hypothesized transmission links between outbreaks were supported while others were refuted. The combined molecular/epidemiologic approach presented here could be applied to other viral populations and potentially to other pathogens for a more thorough view of transmission.

Abstract Background Noroviruses are the most common cause of gastroenteritis outbreaks in industrialised countries. Gastroenteritis caused by Norovirus infection has been described as a highly seasonal syndrome, often referred to as "winter vomiting disease". Methods The Public Health Laboratory Service Communicable Disease Surveillance Centre has systematically collected reports of laboratory confirmed cases of Norovirus-gastroenteritis since 1995. We analysed these data for annual and seasonal trends and age distribution. Results A mid-summer peak in reported cases of Norovirus was observed in 2002, unlike all six previous years when there was a marked summer decline. Total reports from 2002 have also been higher than all previous years. From the first 10 months of 2002, a total of 3029 Norovirus diagnoses were reported compared the previous peak in 1996 of 2437 diagnoses for the whole 12-month period. The increase in 2002 was most marked in the 65 and older age group. Conclusion This surveillance data challenges the view that Noroviruses infections exclusively have wintertime seasonality.

In 2014, 42% of all HIV diagnoses in the East of England were diagnosed late. Individuals unaware of their HIV status will not benefit from lifesaving and infectious-limiting antiretroviral therapy, and they remain at risk of decreased life expectancy and onward transmission of HIV. We sought to identify risk factors associated with late HIV diagnosis in the East of England to inform future HIV testing and prevention strategies relevant to the local population. Data on all HIV infected individuals aged ≥16 years and diagnosed between 2008 and 2014 in the East of England were obtained from the national HIV and AIDS Reporting System. Late diagnosis was defined as CD4 cell count below 350 cells/mm3 within 91 days of diagnosis. Logistic regression investigated risk factors for late HIV diagnosis. A total of 2469 people were included; 1342 (54%) were late HIV diagnoses. In multivariable analysis risk factors for late diagnosis were: age ≥30 years, originating from WHO regions of South-East Asia or Europe (excluding UK), heterosexual orientation and being diagnosed as an inpatient or by a general practitioner. The odds of late diagnosis significantly reduced every year (OR 0.95, 95% CI 0.90-0.99, p = 0.042). Despite this year-on-year reduction continued high rates suggest future HIV testing and prevention strategies should be informed by local regional epidemiology to allow those at greatest risk to be targeted appropriately. [ABSTRACT FROM AUTHOR]

Confirmed isolates of nontoxigenic Corynebacterium diphtheriae in England and Wales increased substantially from 1986 to 1994. Ribotyping of 121 isolates confirmed in 1995 showed that 90 were of a single [...]

We thank the authors [1,2] for the two perspectives on our articles [3,4]. Our study estimated the prevalence of blindness in Mankien at 4%, which Kuper and Gilbert describe as [...]