Vaccination Is More Effective Than Prophylactic Oseltamivir in Preventing CNS Invasion by H5N1 Virus via the Olfactory Nerve.
J Infect Dis 2016;
214:516-24. [PMID:
27448390 DOI:
10.1093/infdis/jiw123]
[Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 03/25/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND
Influenza A viruses can replicate in the olfactory mucosa and subsequently use the olfactory nerve to enter the central nervous system (CNS). It is currently unknown whether intervention strategies are able to reduce or prevent influenza virus replication within the olfactory mucosa and subsequent spread to the CNS. Therefore, we tested the efficacy of homologous vaccination and prophylactic oseltamivir to prevent H5N1 virus CNS invasion via the olfactory nerve in our ferret model.
METHODS
Ferrets were vaccinated intramuscularly or received oseltamivir (5 mg/kg twice daily) prophylactically before intranasal inoculation of highly pathogenic H5N1 virus (A/Indonesia/05/2005) and were examined using virology and pathology.
RESULTS
Homologous vaccination reduced H5N1 virus replication in the olfactory mucosa and prevented subsequent virus spread to the CNS. However, prophylactic oseltamivir did not prevent H5N1 virus replication in the olfactory mucosa sufficiently, resulting in CNS invasion via the olfactory nerve causing a severe meningoencephalitis.
CONCLUSIONS
Within our ferret model, vaccination is more effective than prophylactic oseltamivir in preventing CNS invasion by H5N1 virus via the olfactory nerve. This study highlights the importance of including the olfactory mucosa, olfactory nerve, and CNS tissues in future vaccine and antiviral studies, especially for viruses with a known neurotropic potential.
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