Acute neuropathogenicity with experimental infection of equine herpesvirus 9 in common marmosets (Callithrix jacchus).

The research article revolves around an experimental infection of a common marmoset (a type of primate) with Equine herpesvirus 9 (EHV-9), a new neurotropic equine herpesvirus. The study establishes neurological degeneration in the marmosets post-infection, thereby proving their susceptibility to EHV-9.

Study Objective and Method

The objective of this study relates to assessing the infectivity of EHV-9 in primates, as there has been no information regarding this so far. In this experiment, the researchers inoculated four common marmosets with EHV-9 to evaluate their response.

• Each marmoset was infected through the nasal route with 10(6) plaque-forming units of EHV-9.
• This method helped simulate the natural course of infection where a virus would typically invade a host organism.

Results of the Study

Following inoculation, all the four marmosets exhibited various neurological signs which progressed to collapse. The neurological response is a hallmark of EHV-9 infection, which is neurotropic, meaning that it has a particular affinity for the nervous system.

• Upon histological examination, the marmosets exhibited severe encephalitis characterized by neuronal degeneration and necrosis.
• The presence of intranuclear inclusion bodies was detected in the marmosets, which extended from the olfactory bulb to the rhinencephalon and piriform lobe.
• The authors also observed severe necrotizing rhinitis with prominent intranuclear inclusion bodies in the olfactory mucosa in the nasal cavity of the animals.
• Immunohistochemistry further revealed EHV-9 antigens in the degenerating neuronal cells.

Conclusion

On the basis of these observations, it was concluded that common marmosets are susceptible to EHV-9. This study provides a new understanding of the host spectrum of EHV-9 and its potential threat to different species. More research is needed to further investigate the underlying mechanisms and possible protections.