Some vaccines are made from viruses rendered inactive by chemical treatment. But they have a major drawback: the chemical treatment also makes virus particles less recognizable to the immune system, limiting vaccine effectiveness.

Researchers at Oregon Health & Science University's Oregon National Primate Research Center have found a likely way around this limit by using a hydrogen peroxide treatment to inactivate viruses.

The method rendered viruses noninfective while causing minimal damage to the viral proteins that signal the immune system to attack. The researchers produced effective vaccines against three viral infections tested in mice: West Nile and viruses closely related to lassa fever and small pox. The study appears in the journal

.

Whether vaccines made this way will prove safe and effective in people remains to be shown. OHSU and

, a privately held startup in Beaverton, are developing the vaccine technology. Grants from the National Institutes of Health and OHSU's primate center funded the research.

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