ABSTRACT
The lack of an experimental animal model for the study of dengue pathogenesis is a limiting factor for the development of vaccines and drugs. In previous studies, our group demonstrated the susceptibility of BALB/c mice to infection by dengue virus (DENV) 1 and 2, and the virus was successfully isolated in several organs. In this study, BALB/c mice were experimentally infected intravenously with DENV-4, and samples of their saliva were collected. Viral RNA extracted from the saliva samples was subjected to qRT-PCR, with a detection limit of 0.002 PFU/mL. The presence of DENV-4 viral RNA was detected in the saliva of two mice, presenting viral titers of 109 RNA/mL. The detection of DENV RNA via saliva sampling is not a common practice in dengue diagnosis, due to the lower detection rates in human patients. However, the results observed in this study seem to indicate that, as in humans, detection rates of DENV RNA in mouse saliva are also low, correlating the infection in both cases. This study reports the first DENV detection in the saliva of BALB/c immunocompetent mice experimentally infected with non-neuroadapted DENV-4.
Subject(s)
Humans , Animals , Male , Mice , Saliva/virology , Dengue Virus/isolation & purification , RNA, Viral/isolation & purification , RNA, Viral/genetics , Immunocompromised Host , Viral Load/genetics , Reverse Transcriptase Polymerase Chain Reaction , Dengue Virus/genetics , Disease Models, Animal , Mice, Inbred BALB CABSTRACT
La transmisión vertical es la principal vía de contagio del HIV en la edad pediátrica. El diagnóstico de la infección congénita antes de los 18meses se realiza mediante ensayos virológicos: detección de genoma viral como ARN plasmático y ADN proviral. La sensibilidad de estos ensayos varía según la edad del niño, con valores de especificidad mayores al 95%. El objetivo de este trabajo fue evaluar el desempeño del ensayo de carga viral (CV) COBAS Taqman HIV-1 Test, v1.0 (Roche), y su concordancia con una PCR múltiple anidada in-house para la detección del ADN proviral. De 341 muestras procesadas, 15 resultaron positivas y 326 negativas por ambas metodologías. Para la metodología de CV, la sensibilidad general fue del 88,2% y la especificidad del 100%. Nuestros resultados indican que la metodología de CV evaluada puede utilizarse como técnica alternativa para el diagnóstico de infección congénita por HIV
Vertical transmission is the main route of HIV infection in childhood. Because of the persistence of maternal HIV antibodies, virologic assays that directly detect HIV are required to diagnose HIV infection in infants younger than 18months of age. The sensitivity of HIV RNA/DNA assays increases as the child becomes older. These tests have specificity values greater than 95%. The aim of this study was to evaluate the performance of the COBAS Taqman HIV-1 Test, v1.0 assay (Roche) and its concordance with a Multiplex Nested-PCR. Of 341 samples processed, 15 were positive and 326 negative by both methods. Sensitivity and specificity overall values for the viral load assay were 88.2% and 100%, respectively. Our results indicate that the COBAS Taqman assay evaluated could be used as an alternative method to diagnose HIV congenital infection