Nine Adenovirus (Ad) strains isolated in Cuba, from 128 nasopharingeal swab specimens of children below five years old, with acute respiratory diseases, during 1996 and 1997, were studied by restriction enzyme analysis of genomic DNA with two endonucleases BamH I and Sma I. All different fragment patterns were compared with the respective prototypes. The identified adenoviruses were Ad 1 (n=4), Ad 2 (n=1) and Ad 6 (n=4). Males were more frequently infected than females. The analysis of the occurrence of these Adenovirus strains of subgenus C revealed that Ad 1 and Ad 6 were the predominant serotypes in 1996 and in 1997, respectively.

Twenty-six human respiratory syncytial virus strains (subgroup A) isolated from three outbreaks in Havana City during the period 1994/95, 1995/96 and 1996/97 were analyzed to determine their antigenic and genetic relationships. Analyses were performed by monoclonal antibodies and restriction mapping (N gene) following amplification of the select region of the virus genome by polymerase chain reaction. All isolated strains were classified as subgroup A by monoclonal antibodies and they showed a restriction pattern NP4 that belonged to subgroup A. Thus the results obtained in this work, showed a close relation (100%) between antigenic and genetic characterization of the isolated strains in our laboratory. These methods permit the examination of large numbers of isolates by molecular techniques, simplifying the researchs into the molecular epidemiology of the virus.

The aim of this study was to develop a polymerase chain reaction (PCR) for the detection of respiratory syncytial virus (RSV) genomes. The primers were designed from published sequences and selected from conserved regions of the genome encoding for the N protein of subgroups A and B of RSV. PCR was applied to 20 specimens from children admitted to the respiratory ward of "William Soler" Pediatric Hospital in Havana City with a clinical diagnosis of bronchiolitis. The PCR was compared with viral isolation and with an indirect immunofluorescence technique that employs monoclonal antibodies of subgroups A and B. Of 20 nasopharyngeal exudates, 10 were found positive by the three assayed methods. In only two cases, samples that yielded positive RNA-PCR were found negative by indirect immunofluorescence and cell culture. Considering viral isolation as the "gold standard" technique, RNA-PCR had 100% sensitivity and 80% specificity. RNA-PCR is a specific and sensitive technique for the detection of the RSV genome. Technical advantages are discussed

An ultramicroELISA assay of double antibody for the detection of IgG antibodies to the respiratory syncytial virus (RSV) wasstandardized. It was used a RVS antiprotein F monoclonal antibody produced by the Genetic Engineering and Biotechnology Center (GEBC) in Havana. The use of this antibody allowed to include crude antigenic preparations instead of purified fractions, which caused a significant reduction of the reactivity obtained with the antigen control. The assay conditions were determined by crossed titration. It was obtained a sensitivity of 97.2 %, a coincidence of 91 %, and a specificity of 83.3 % of the UMELISA as regards the complement fixation. The results may be qualitatively expressed or by antibody titres using only one serum dillution (1:40) and a pattern curve.

Se normalizó un ensayo de ultramicroELISA de doble anticuerpo para la detección de anticuerpos IgG al virus sincitial respiratorio (VSR), para ello se dispuso de un anticuerpo monoclonal antiproteína F del VSR, producido por el Centro de Ingeniería Genética y Biotecnología de La Habana (CIGB). La utilización de este anticuerpo posibilitó la inclusión de preparaciones antigénicas crudas en lugar de fracciones purificadas, lo que disminuye notablemente la reactividad obtenida con el control de antígeno. Las condiciones del ensayo fueron determinadas mediante titulación cruzada y se obtuvo una sensibilidad de 97,2 %, un 91 % de coincidencia y una especificidad 83,3 % del UMELISA con respecto a la fijación del complemento. Los resultados pueden ser expresados cualitativamente o en títulos de anticuerpos empleando una sola dilución de suero (1:40) y una curva patrón.

A high number of acute respiratory diseases was detected among children under one year admitted in a hospital of Havana City. 25 respiratory syncytial virus strains were obtained from 93 patients studied. Viral isolations were multiplied in HEP-2 cells and after observing a cytopathic effect of 80 %, they were classified into subgroups by the indirect immunofluorescence technique, using anti-protein G antibodies from the respiratory syncytial virus. All the samples studied were classified within subgroup A. It is the first time a study like this is conducted in our country, which allowed us to deepen into the viral cause of these diseases and to know that the subgroup A of the respiratory syncytial virus circulated during the outbreak.

Se detectó un alto número de casos de enfermedades respiratorias agudas en niños menores de 1 año, ingresados en un hospital de Ciudad de La Habana. De 93 pacientes estudiados se obtuvieron 25 cepas del virus sincitial respiratorio. Los aislamientos virales fueron multiplicados en células HEP-2, y después de observarse un efecto citopático del 80 % se clasificaron en subgrupos por la técnica de inmunofluorescencia indirecta, utilizando anticuerpos anti-proteína G del virus sincitial respiratorio. Todas las muestras estudiadas se clasificaron dentro del subgrupo A. Este tipo de estudio es el primero realizado en nuestro país, lo cual nos permitió profundizar en la causa viral de estas enfermedades y conocer que durante el brote circuló el subgrupo A del virus sincitial respiratorio.

Immunofluorescence and immunoperoxidase test directed against early viral antigens, and DNA-DNA hybridization were compared with viral isolation for their abilities to detect Cytomegalovirus (CVM) in the urine of 89 HIV infected patients. From the 100 urine samples collected, 70 were found positive by at least one method. Considering viral isolation as the "gold standard" technique, immunofluorescence and immunoperoxidase had a sensitivity of 92.3% and88% respectively, with a specificity in both cases of 95%. DNA-DNA hybridization showed a sensitivity of 90% but with lower (60%) specificity. All of the three assays were effective in detecting CVM from urine and the technical advantage of each is discussed.

An Immunoperoxidase assay was applied to detect early antigens of Cytomegalovirus (CMV) in 150 urine samples from immunocompromised patients, using the commercial available monoclonal antibody against CMV El3. The detection of early antigen by IP (IPCMV) is compared to the conventional cell culture isolation regarding specificity and sensitivity in order to evaluate is usefulness in the diagnostic of CMV infections. The IPCMV showed a sensitivity of 89.8% and a specificity of 91.3% when compared to the isolation method. The great advantage of the IPCMV is based on the shorter time results are achieved, since 48-72 Hs can be enough to provide evidence of CMV infection, while in the isolation technique cytopatho-genic effect was present around 14 days after sample inoculation.

En el presente estudio se comparó la técnica de inmunoperoxidasa para la detección de citomegalovirus (IPCMV) utilizando anticuerpos monoclonales que reconocen proteínas precoces virales con el método convencional de aislamiento viral en fibroblastos humanos. Un total de 150 muestras de orina fueron examinadas encontrando una sensibilidad de un 89.8% y una especificidad de 91.3% de la técnica de IPCMV comparada con el aislamiento viral. Una de las ventajas que presentó la IPCMV fue la rapidez con que fueron obtenidos los resultados (48 horas) mientras que el aislamiento viral fue como promedio 14 días.