# Seroprevalence of adeno-associated virus types 1, 2, 3, 4, 5, 6, 8, and 9 in a Basque cohort of healthy donors

## TL;DR

This study examines how common adeno-associated virus infections are among healthy people in the Basque Country, showing which virus types are most and least common.

## Contribution

The study provides new seroprevalence data for eight AAV serotypes in a unique Basque population, highlighting potential for AAV-based therapies.

## Key findings

- AAV3 had the highest seroprevalence in the Basque population.
- Less than 50% of the population had neutralizing antibodies against AAV4, AAV6, and AAV9.
- The Basque population shows lower immunity to certain AAV serotypes compared to others.

## Abstract

Adeno-associated viruses (AAVs) are promising gene therapy vectors, but challenges arise when treating patients with preexisting neutralizing antibodies. Worldwide seroprevalence studies provide snapshots of existing immunity in diverse populations. Owing to the uniqueness of the Basque socio-geographical landscape, we investigated the seroprevalence of eight AAV serotypes in residents of the Basque Country. We found the highest seroprevalence of AAV3, and the lowest seroprevalence of AAV9. Additionally, less than 50% of the Basque population has neutralizing antibodies against AAV4, AAV6, and AAV9. Our findings provide insight into AAV infections in the Basque region, public health, and the development of AAV-based therapeutics.