# Durable humoral immunity and long-term protection induced by a Crimean-Congo hemorrhagic fever virus replicon particle vaccine in mice

## TL;DR

A vaccine for Crimean-Congo hemorrhagic fever virus provides long-term immunity and protection in mice.

## Contribution

The study demonstrates durable humoral immunity and long-term protection from a replicon particle vaccine.

## Key findings

- IgG responses persisted up to 18 months in mice.
- Protective efficacy reached ≥75% at 6 months and up to 12 months.
- Booster dosing improved antibody avidity and long-term protection.

## Abstract

A Crimean-Congo hemorrhagic fever virus replicon particle vaccine was evaluated for long-term immunity and efficacy in mice. IgG responses persisted up to 18 months, with similar titers across dosing strategies through 12 months. Protective efficacy reached ≥75% at 6 months (prime-only) and up to 12 months (prime-boost). Booster dosing enhanced antibody avidity, effector function, and improved long-term protection. These findings support durable immunity from single or boosted vaccination.