Antigenic and Genetic Characterization of Twenty-six Strains of Human Respiratory Syncytial Virus (Subgroup A) Isolated During Three Consecutive Outbreaks in Havana City, Cuba

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 percent) 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

Analysis of respiratory syncytial virus in clinical samples by reverse transcriptase-polymerase chain reaction restriction mapping

The aim of this study was to develop a polymerase chain reation (PCR) for 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 respirary 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 per cent sensitivity and 80 per cent specificity. RNA-PCR is a specific and sensitive technique for the detection of the RSV genome. Technical advantages are discussed.

Diagnóstico virológico de un brote de fiebre y rash producido por Parvovirus B19, Cuba, 1995 / Virologycal diagnosis of an aoutbreak of fever and rash caused by Parvovirus B19, Cuba, 1995

Se reportan los resultados obtenidos en el estudio de un brote de fiebre y rash ocurrido en Ciudad de La Habana en marzo de 1995. En las muestras de 35 pacientes se descartaron dengue, sarampión, rubéola, herpes simple y Epstein Barr como agentes causales del brote. Mediante la detección de anticuerpos IgM y la técnica de reacción en cadena de la polimerasa (RCP) se identificó al Parvovirus B19 como agente causal del brote. En 14/18 muestras (77,7 por ciento) se comprobó la infección por este agente por alguna de las técnicas empleadas. Este estudio se refiere al primer brote confirmado de Parvovirus B19 en Cuba

Estudio serológico en una población infantil con antígenos de gripe humana y animal / Serologic study in an infantile population with antigens of human and animal influenza

Se realizó un estudio serológico con 600 monosueros de niños entre 0 y 14 años por la técnica de inhibición de la hemeglutinación con sueros procedentes del Hospital Pediátrico Docente de Centro Habana. Este estudio abarcó desde octubre de 1982 hasta marzo de 1983. Se utilizaron 20 antígenos de virus de gripe tipo A de variadas fórmulas antigénicas de origen humano y animal. Los tantos por cientos más altos de sueros positivos se correspondieron con los de fórmula antigénica H3N2 y los más bajos con los de fórmula antigénica H1N1. No se encontró positividad al resto de los subtipos de origen humano ni animal