Twice upon a time: The progression of canine visceral leishmaniasis in an Argentinean city.

Canine Visceral Leishmaniasis (CVL) prevalence, spatial distribution and associated factors were assessed in four locations in Iguazú department in 2014 and in Puerto Iguazú city again in 2018. The city areas were divided into a grid of 400x400m cells. All cells were sampled in 2014 and a random subsampling was developed in 2018. In each cell, five dogs clustered in a 'critical scenario' (prone to have vectors) were sampled. A rapid immunochromatographic dipstick was used to detect antibodies against Leishmania infantum, confirming by lymph node smears observation and PCR. For Puerto Iguazú, Generalized Linear Models (GLMs) were constructed considering environmental, dog and clinical variables. Pearson's Chi square and Fisher's exact tests were employed to evaluate the association between CVL, dog clinical signs and infestation with other parasites. Cartographic outputs were made and Moran's I indices were calculated as spatial autocorrelation indicators. CVL prevalence rates were 26.18% in 2014 and 17.50% in 2018. No associations were established in environmental models, but dog age and repellent use were significant when running 2014 dog models. Clinical models showed significant associations between seropositive dogs and ophthalmological, dermal signs and onychogryphosis in 2014. In 2018, only adenomegaly was associated. The results of global Moran´s I were not significant but regarding local analysis, six sites in 2014 and one in 2018 presented autocorrelation with neighboring sites. The decrease in CVL prevalence may be associated to transmission stabilization, which could explain the lack of associations with dog-related variables. Further, spatial distribution of CVL is a poor evidence for design of transmission control measures but could be important in case of intensive parasite circulation or when the first autochthonous cases appear. For control success, sensitivity of diagnostic methods, political will and adequate material resources remain critical. Modeling of multiple variables will be required to identify factors that drive disease stabilization/destabilization.

Circulación de virus Dengue: triage clínico-laboratorial / Dengue virus circulation: clinical-laboratory triage

INTRODUCCIÓN En la infección por DENV, la mayoría de casos se refiere como SFI y requiere confirmación de laboratorio. La vigilancia laboratorial se realiza con ELISAs NS1/IgM y en laboratorios de referencia por PRNT y RT-PCR. En este contexto, las estrategias de triage basadas en evidencia que identifican primeros estadios pueden facilitar la caracterización del paciente en función del manejo clínico-laboratorial. OBJETIVO Evaluar desarrollo de triage clínico-laboratorial que facilite la caracterización de SFI por DENV. MÉTODOS Estudio prospectivo de evaluación de precisión diagnóstica de metodología clínica-laboratorial, basado en algoritmo clínico con capacidad de diferenciar al paciente con sospecha de DENV de SFI seguido de ELISA NS1/IgM, en escenario epidémico y endemo-epidémico, al efecto de evaluar la performance de prueba índice (algoritmo clínico-laboratorial) vs. prueba referencia (PRNT/PCR) por Epidat 3.1. RESULTADOS El número de casos fue menor al esperado, por lo cual no se ha evaluado aún la performance del ensayo. El tamaño muestral fue 27 pacientes. De los síntomas clínicos, eritema pos 72 horas ha sido el único diferencial en pacientes NS1/IgM-DENV (+). Otros síntomas ofrecen escasa potencialidad diagnóstica diferencial para pacientes con DENV. El caso de ZikV presentó conjuntivitis, eritema pre 72 horas y petequias. En ensayos de laboratorio (n=13) se obtuvieron 2 PCR Flavivirus (+), 1 PCR ZikaV (+) y 10 PRNT (+) para diferentes combinaciones de DenV, Ilheus, SLEV, WNV. En un paciente con NS1/IgM-DENV negativas se observó 1 PRNT DenV (+). DISCUSIÓN La escasa potencialidad diagnóstica diferencial para DENV y los resultados de PCR/PRNT acomplejan el escenario epidemiológico local, que podría estar sustentado en circulación viral por vectores en base al hallazgo reciente de otros autores. Los resultados expuestos son preliminares, el grupo de investigación asume el compromiso de proseguir con el trabajo hasta alcanzar el objetivo propuesto