Evaluation of antimicrobial efficacies of chlorine dioxide gas released into the air towards pathogens present on the surfaces of inanimate objects.

The efficacy of ClO2 gas, as surface disinfectant at around 1,000 ppb against avian orthoavulaviruses type 1 (AOAV-1), infectious bronchitis virus (IBV), Escherichia coli (EC), and Salmonella Enteritidis (SE) was evaluated at the required level (≥99.9% reduction) on various surfaces. Exposing the surfaces to ClO2 gas for 1 hr reduced AOAV-1, except for rayon sheets which required 3 hr. However, 1 hr of exposure did not effectively reduced IBV titer. In the case of EC, glass plates and plastic carriers needed 1 hr of exposure, while rayon sheets required 2 hr. SE on rayon sheets required 1 hr exposure, but on the other tested surfaces showed inadequate reduction. Overall, ClO2 gas is an effective disinfectant for poultry farms.

Isolation and Molecular Characterization of Fowl Adenovirus and Avian Reovirus from Breeder Chickens in Japan in 2019-2021.

Fowl adenoviruses (FAdVs) and avian reoviruses (ARVs) are ubiquitous in poultry farms and most of them are not pathogenic, yet often cause damage to chicks. A total of 104 chicken fecal samples were collected from 7 farms of breeder chickens (layers and broilers) in Japan from 2019 to 2021, and yielded 26 FAdV plus 14 ARV isolates. By sequencing, FAdV isolates were classified as FAdV-1, 5 and 8b. ARV isolates were classified as genotype II, IV and V. These results suggest that FAdVs and ARVs are resident in the breeder chicken farms in Japan.

Synergistic effects of quaternary ammonium compounds and food additive grade calcium hydroxide on microbicidal activities at low temperatures.

The microbicidal activities of mixtures of quaternary ammonium compounds (QACs) and food additive grade calcium hydroxide (FdCa(OH)2) were evaluated in a suspension test at -20°C using an anti-freeze agent (AFA) containing methanol, or at 1°C, with varying contact time, toward avian influenza virus (AIV), Newcastle disease virus (NDV), fowl adenovirus (FAdV), avian reovirus (ARV), Salmonella Infantis (SI) and Escherichia coli (EC). At -20°C, the mixtures could inactivate AIV and NDV within 30 min, FAdV and ARV within 5 sec, and SI and EC within 3 min, respectively. AFA did not inactivate viruses and bacteria within 30 min and 10 min, respectively. At 1°C, the mixtures inactivated FAdV and ARV within 30 sec, AIV within 10 min, and NDV within 30 min. A mixture of slaked lime (SL) and QAC could inactivate FAdV and ARV within 30 sec, but could not inactivate AIV and NDV even after 60 min at 1°C. SL could not substitute FdCa(OH)2 in order to exert the synergistic effects with QAC. Thus, QACs microbicidal activities were maintained or enhanced by adding FdCa(OH)2. It is hence recommended to use QACs with FdCa(OH)2, especially in the winter season.