Langat virus

Langat virus (LGTV) is a virus of the genus Flavivirus. The virus was first isolated in Malaysia in 1956 from a hard tick of the Ixodes genus.^[1] This virus is antigenically related to Omsk hemorrhagic fever virus, Kyasanur forest disease virus, Alkhurma virus, Louping ill virus and other viruses of the tick-borne encephalitis virus (TBEV) complex. The Langat virus does not pose a significant epidemiological threat in comparison with TBEV. There are no known cases of human diseases associated with LGTV.^[2] The Malaysian strain (LGT strain TP21, also known as the Yelantsev virus) is naturally attenuated and induces neutralizing antibodies to tick-borne encephalitis virus (TBEV) and protection against other TBEV complex viruses in animals.^[3]

LGTV-based vaccine

In the 1970s a live attenuate LGTV-based vaccine against tick-borne encephalitis was made. At the same time, another vaccine was tested, but the group vaccinated with the LGTV-based vaccine had the lowest level of developing infection decease.^[4] However, there were two major problems: the relatively high rate of incidents of encephalitis (1:10,000) and lack of absolute protection from infection in endemic regions.

References

El Virus de Langat (LGTV) es un virus del género Flavivirus.^[1]​ El virus se aisló por primera vez en Malasia en 1956 a partir de una garrapata del género Ixodes.^[2]​Este virus está relacionado antigénicamente con el virus de la fiebre hemorrágica de Omsk, el virus de la enfermedad de la selva de Kyasanur, el virus de Alkhurma, el virus de Louping y otros virus del complejo de los virus de la encefalitis por garrapatas (TBEV). El virus de Langat no representa una amenaza epidemiológica significativa en comparación con TBEV. No se conocen casos de enfermedades humanas asociadas con LGTV.^[3]​La cepa de Malasia (cepa LGT TP21, también conocida como el virus Yelantsev) se atenúa naturalmente e induce anticuerpos neutralizantes contra el Virus de la encefalitis por garrapatas y la protección contra otros virus complejos TBEV en animales.^[4]​

Vacuna

En la década de 1970 se realizó una vacuna viva atenuada basada en LGTV contra la encefalitis transmitida por garrapatas. Al mismo tiempo, se probó otra vacuna, pero el grupo vacunado con la vacuna basada en LGTV fue el que tuvo menores niveles de desarrollo de la enfermedad.^[5]​Sin embargo, hubo dos grandes problemas: la tasa relativamente alta de incidentes de encefalitis (1:10 000) y la falta de protección absoluta contra la infección en regiones endémicas.

Referencias

Il Langat virus (LGTV) è un arbovirus della famiglia Flaviviridae, genere Flavivirus, appartiene al IV gruppo dei virus a ((+) ssRNA). ^[1]

Il virus ha come vettore la zecca Ixodes Granulatus mentre l'animale ospite è sconosciuto.^[2]

Il virus fa parte dei Flavivirus patogeni per l'uomo ed è causa di encefalite nell'uomo.^[2]

Note

Bibliografia

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