Schmallenberg virus was first detected in Germany in October 2011, associated with congenital malformations in cattle, sheep and goats. This novel emergent agent causes mild disease in cattle with decreased milk production, fever and diarrhea. In March 2012, the German Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, reported the development and validation of a real-time RT-PCR for the diagnosis of this new virus. The Animal Virology Laboratory at the National Center for Animal and Plant Health in Cuba has adapted the protocol previously reported on the LightCycler platforms using two different mix conditions. In all cases, amplification curves obtained were specific and all the dilutions tested showed an increase in the Ct-values. Nevertheless, the sensitivity of the test was not affected. Thus, the test for Schmallenberg virus detection is enabled for the possible emergency of this agent in Cuba.

El virus de Schmallenberg fue diagnosticado por primera vez en octubre de 2011 en Alemania, asociado a malformaciones congénitas en bovinos, ovinos y cabras. Este nuevo agente emergente causa enfermedad ligera en bovinos, con disminución de la producción de leche, fiebre y diarreas. En marzo de 2012 se reportó el desarrollo y validación de un RT-PCR en tiempo real para el diagnóstico de este nuevo virus por el grupo alemán del Institute of Diagnostic Virology, Friedrich-Loeffler-Institut. El Laboratorio de Virología Animal del Centro Nacional de Sanidad Agropecuaria, en Cuba, adaptó el protocolo previamente reportado a la plataforma de LighCycler usando dos condiciones de mezcla diferentes. En todos los casos las curvas de amplificación obtenidas fueron específicas y todas las diluciones evaluadas mostraron un incremento en los valores de Ct. A pesar de esto, la sensibilidad de la técnica no se afectó. Por lo tanto, la técnica para la detección del virus de Schmallenberg está disponible ante la posible emergencia de este agente en Cuba.

Avian infectious bronchitis virus (IBV) and bovine coronavirus (BCoV) are pathogens of veterinary importance that affect birds and bovine in Cuba; however, molecular characteristics and genetic diversity of these viruses are unknown. This study was aimed at determining the molecular characteristics and genetic diversity of both agents, based in the spike S gene. A molecular analysis was carried out from field strains of BCoV collected between 2009 and 2011 and phylogenetic studies were conducted using partial or complete S gene sequences as phylogenetic markers. Besides, studies of phylogenetic inference were carried out in S1 region of recent isolates of IBV. All Cuban bovine coronavirus sequences were located in a single cluster supported by 100 % bootstrap and 1.00 posterior probability values. The Cuban BCoV sequences were also clustered with the USA BCoV strains corresponding to the GenBank accession numbers EF424621 and EF424623, suggesting a common origin for these viruses. This phylogenetic cluster was also the only group of sequences in which no recombination events were detected. Of the 45 amino acid changes found in the Cuban strains, four were unique. On the other hand, two putative genotypes genetically different to the Massachusetts genotype H120 strain used in the Cuban vaccination program were found in the flocks assessed. In addition, a potential nephropathogenic IBV isolate was found by first time in Cuba. This research won the 2012 Award of the Cuban National Academy of Sciences.

El virus de la bronquitis infecciosa aviar (IBV) y el coronavirus bovino (BCoV) son agentes patógenos de importancia veterinaria porque afectan a las aves y al ganado bovino en Cuba. Como se desconocen sus características moleculares y diversidad genética, el objetivo de esta investigación fue determinarlas en ambos agentes, a partir del gen de la espícula S. Se analizaron cepas de campo de BCoV, recolectadas entre los años 2009 y 2011, y se compararon filogenéticamente según varios marcadores del gen S. Además se hicieron estudios de inferencia filogenética en una región de S1 de aislados recientes del IBV. Todas las cepas de BCoV cubanas se localizaron en un mismo grupo filogenético con un soporte estadístico del 100 % y valor de probabilidad posterior 1.00. Las secuencias de coronavirus bovino cubanas se agruparon con cepas de BCoV de EE.UU. con números de acceso en el GenBank de EF424621 y EF424623, que sugiere un origen común para estos virus. Este grupo filogenético fue el único en cuyas secuencias no se detectaron eventos de recombinación. De los 45 cambios de aminoácidos en las cepas cubanas, cuatro fueron únicos. En las granjas evaluadas se detectaron dos posibles genotipos genéticamente diferentes al genotipo Massachusetts de la cepa H120 usada en el programa de vacunación cubano. Además, se halló un potencial aislado de IBV nefropatogénico encontrado por primera vez en Cuba. Este trabajo mereció el Premio Anual de la Academia de Ciencias de Cuba del año 2012.

Encephalomyocarditis virus (EMCV) infections can cause losses in pig farms all over the world. Rapid, sensitive and unequivocal detection of this virus is therefore essential for the diagnosis and control of the disease. An RT-PCR assay was developed, optimized and evaluated for encephalomyocarditis virus detection in organ based on a pair of primers that amplifies a 165 bp DNA fragment from a highly conserved nucleotide region of the viral 3D glycoprotein. PCR products of the expected size were obtained from Cuban EMCV 744/03 strain. Non-specific reactions were not observed when other porcine RNA genome viruses and uninfected cells were used. The analytical sensitivity of the test was estimated to be 2 TCID50/50 mL. The analysis of tissue homogenate samples from naturally infected animals proved the potential usefulness of the method for a rapid disease diagnosis from field cases.

A doença de Aujeszky, também conhecida como pseudo-raiva, causa perdas econômicas graves na indústria suína e afeta a criação de suínos em todo o mundo. O procedimento de diagnóstico convencional é demorado, podendo ocorrer resultados falso-negativos em animais infectados de forma latente. Este estudo apresenta o desenvolvimento, otimização e avaliação de um ensaio de Reação de Polimerase em Cadeia para o diagnóstico da pseudo-raiva. O ensaio baseou-se na amplificação do fragmento genético viral gD altamente conservado. Os produtos da PCR de tamanho esperado foram obtidos a partir de isolados de PRV. Não foram observadas reações inespecíficas quando foram testados herpes-vírus relacionados, outros vírus DNA de suínos e células não infectadas. A sensibilidade analítica estimada do teste foi 1,34 TCID50/50 uL. A análise de homogenatos feitos com tecidos de animais naturalmente infectados mostrou que o método é útil para o diagnóstico rápido da doença no campo, sendo um ensaio rápido, sensível e específico para detectar o vírus da pseudo-raiva em amostras clinicas.

Aujeszky's disease, also known as pseudorabies causes severe economic losses in swine industry and affects the pig husbandry all over the world. The conventional diagnostic procedure is time-consuming and false-negative results may occur in submissions from latently infected animals. The development, optimization and evaluation of a polymerase chain reaction (PCR) assay are presented for the diagnosis of pseudorabies infection. This assay was based on the amplification of a highly conserved viral gD gene fragment. PCR products of the expected size were obtained from PRV strains. Non-specific reactions were not observed when a related herpesvirus, other porcine DNA genome viruses and uninfected cells were used to assess PCR. The analytical sensitivity of the test was estimated to be 1.34 TCID50/50 uL. The analysis of tissue homogenate samples from naturally infected animals proved the potential usefulness of the method for a rapid disease diagnosis from field cases. A rapid, sensitive and specific PCR-based diagnostic assay to detect pseudorabies virus in clinical samples is provided.