# Disinfection by hydrogen peroxide nebulization increases susceptibility to avian pathogenic Escherichia coli

## TL;DR

Nebulizing hydrogen peroxide in chicken environments may increase their vulnerability to a dangerous type of E. coli infection.

## Contribution

This study reveals that hydrogen peroxide nebulization can increase susceptibility to avian pathogenic Escherichia coli.

## Key findings

- Chickens exposed to 2% hydrogen peroxide had higher lesion scores and more E. coli in their spleens.
- Even 1% hydrogen peroxide exposure increased E. coli concentrations compared to controls.
- Hydrogen peroxide nebulization is contraindicated for use in chicken environments due to increased infection risk.

## Abstract

Avian pathogenic Escherichia coli (APEC) are the major cause of economic losses in the poultry industry worldwide. Traditionally, antibiotics are used to treat and prevent colibacillosis in broilers. Due to resistance development other ways of preventing/treating the disease have to be found. Therefore during this study the nebulization of low concentrations of hydrogen peroxide (H2O2) was tested in the presence of chickens to lower pathogenicity of APEC.

Significantly higher total lesion scores and higher E. coli concentrations were found in the spleen of chickens exposed to 2 % H2O2 compared to those exposed to 1 % H2O2 and control chickens which had been exposed to nebulization with distilled water. Higher total lesions scores and E. coli concentrations in the spleen were found in chickens exposed to 1 % H2O2 in comparison to control chickens (not significant).

H2O2 is rendering animals more prone to APEC infection contraindicating H2O2 nebulization in the presence of chickens.