SARS-CoV-2 Modelo de Inoculación en la Cavidad Oral. Revisión de la Literatura / SARS-CoV-2 Model of Inoculation in the Oral Cavity. Literature Review

RESUMEN: El virus SARS-CoV-2 ingresa al organismo de un individuo susceptible a través de la cavidad oral, nasal o de la mucosa conjuntival; busca ensamblarse por medio de su glicoproteína de superficie o espiga con los receptores de la enzima convertidora de angiotensina 2 que en boca los encontramos con mayor expresión en las células escamosas que recubren el epitelio lingual y las glándulas salivales, una vez que ingresa por medio de la activación de proteasas ingresa a la célula huésped para denudar su RNA viral, a diferencia de otros virus no necesita ir hasta el núcleo de tal forma que en el citoplasma inicia su replicación y utiliza los ribosomas del huésped para formar una gran cantidad de proteínas virales tanto estructurales como accesorias que le permita formar nuevos viriones potencialmente infecciosos; los estomatólogos deben tomar en cuenta esta vía de infección y extremar las medidas para disminuir su carga viral local en la cavidad oral y las barreras físicas de protección para el operador, el paciente y la ergonomía del consultorio.

ABSTRACT: SARS-CoV-2 virus enters the body of a susceptible individual through oral, nasal or conjunctival mucosa, seeking to bind to the spike glycoprotein surface through angiotensin-converting enzyme 2 receptors. These are found in the mouth with a higher expression in oral squamous cells that cover the lingual epithelium and salivary glands. Once proteolytic activation begins, it enters the host cell to denudate its viral RNA. In contrast with other viruses, it does not require nucleus access, and therefore replicates in the cytoplasm using the host's ribosomes to produce great amounts of both structural and accessory viral proteins. Since this generates new and potentially infectious virions, dentists must consider this route of infection and take extreme measures to decrease their viral load in the oral cavity. Physical protection barriers for the operator, the patient and the health and safety of the work place are critical in these cases.

Detection of porcine reproductive and respiratory syndrome virus in oral fluid from naturally infected pigs in a breeding herd

The objectives of the present study were to evaluate the anatomic localization of porcine reproductive and respiratory syndrome virus (PRRSV) in naturally infected pigs and to determine whether oral fluid could be used to detect the virus in infected animals. Two sows, seven 2-month-old grower pigs, and 70 6-month-old gilts were included in this study. PRRSV in sera and oral fluid were identified by nested reverse transcription PCR (nRT-PCR) while lung, tonsil, and tissue associated with oral cavity were subjected to nRT-PCR, immunohistochemistry, and in situ hybridization. In sows, PRRSV was identified in oral fluid and tonsils. PRRSV was also detected in oral fluid, tonsils, salivary glands, oral mucosa, and lungs of all seven grower pigs. However, viremia was observed in only two grower pigs. Double staining revealed that PRRSV was distributed in macrophages within and adjacent to the tonsillar crypt epithelium. In gilts, the North American type PRRSV field strain was detected 3 to 8 weeks after introducing these animals onto the farm. These results confirm previous findings that PRRSV primarily replicates in tonsils and is then shed into oral fluid. Therefore, oral fluid sampling may be effective for the surveillance of PRRSV in breeding herds.

Vírus rábico em morcego Nyctinomops laticaudatus na Cidade do Rio de Janeiro, RJ: isolamento, titulação e epidemiologia / Rabies virus in Nyctinomops laticaudatus bats in the City of Rio de Janeiro: isolation, titration and epidemiology

Apresenta-se o primeiro relato de raiva em morcego da espécie Nyctinomops laticaudatus, na Cidade do Rio de Janeiro, RJ. Foram realizados isolamento e titulação viral em diferentes tecidos, encontrando-se altos títulos no cérebro e glândulas salivares. A ocorrência de raiva em uma espécie pouco freqüente neste estado sugere que a doença pode ser mais prevalente do que aparenta.

The first case report of rabies in bats of the species Nyctinomops laticaudatus, in the city of Rio de Janeiro City, is presented. Virus isolation and titration were performed in different tissues, and high titers were found in the brain and salivary glands. Rabies occurrence in such an infrequent species in this state suggests that the disease may be more prevalent than it appears to be.