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Bioceramic derived from chicken feces (BCX) is a material produced by a sintering process for the purpose of use in animal farms to control livestock infectious diseases. In the present study, BCX at pH 13 was evaluated for the durability of its virucidal activity in simulated field conditions. First it was shown that BCX had activity toward Newcastle disease virus, infectious bursal disease virus, and goose parvovirus within 3 min and toward avian influenza virus (AIV) within 1 hr. BCX was further tested by keeping it under simulated harsh environmental conditions with sunlight for several weeks as well as by repeatedly soaking it with water and drying under sunlight many times. After sampling every 2 consecutive weeks and every 2 (of 9) consecutive resuspensions, BCX was evaluated for its efficacy against AIV. Evaluation under the harsh conditions illustrated that BCX could retain its satisfactory efficacy toward AIV throughout 7 wk and through 9 resuspensions. It is hence concluded that BCX is an excellent material for applying in livestock farming as a trapping disinfectant, due to its efficacy to inactivate various viruses, and that this efficacy is prolonged even under harsh environmental conditions.

Hypochlorous acid (HOCl) solutions were evaluated for their virucidal ability against a low pathogenic avian influenza virus (AIV), H7N1. HOCl solutions containing 50, 100 and 200 ppm chlorine (pH 6) or their sprayed solutions (harvested in dishes placed at 1 or 30 cm distance between the spray nozzle and dish) were mixed with the virus with or without organic materials (5% fetal bovine serum: FBS). Under plain diluent conditions (without FBS), harvested solutions of HOCl after spraying could decrease the AIV titer by more than 1,000 times, to an undetectable level (< 2.5 log10TCID50/ml) within 5 sec, with the exception of the 50 ppm solution harvested after spraying at the distance of 30 cm. Under the dirty conditions (in the presence of 5% FBS), they lost their virucidal activity. When HOCl solutions were sprayed directly on the virus on rayon sheets for 10 sec, the solutions of 100 and 200 ppm could inactivate AIV immediately after spraying, while 50 ppm solution required at least 3 min of contact time. In the indirect spray form, after 10 sec of spraying, the lids of the dishes were opened to expose the virus on rayon sheets to HOCl. In this form, the 200 ppm solution inactivated AIV within 10 min of contact, while 50 and 100 ppm could not inactivate it. These data suggest that HOCl can be used in spray form to inactivate AIV at the farm level.

Scallop shell powder produced by calcination process − the average diameter of the powder particles being 20 µm (SSP) − was further ground into nano-sized particles, with average diameter of 500 nm, here designated CaO-Nano. Solution of CaO-Nano could inactivate avian influenza virus within 5 sec, whereas the solution of SSP could not even after 1 hr incubation. CaO-Nano solution could also inactivate Newcastle disease virus and goose parvovirus within 5 sec and 30 sec, respectively. The virus-inactivating capacity (neutralizing index: NI>3) of the solution was not reduced by the presence of 20% fetal bovine serum. CaO-Nano solution seems to be a good candidate of materials for enhancement of biosecurity in farms.

Existence of bioaerosol contaminants in farms and outbreaks of some infectious organisms with the ability of transmission by air increase the need for enhancement of biosecurity, especially for the application of aerosol disinfectants. Here we selected slightly acidic hypochlorous acid water (SAHW) as a candidate and evaluated its virucidal efficacy toward a virus in the air. Three-day-old conventional chicks were challenged with 25 doses of Newcastle disease live vaccine (B1 strain) by spray with nebulizer (particle size

The efficacy and stability of scallop shell powder (SSP) were investigated, in terms of its capacity to inactivate avian influenza virus (AIV), and compared with slaked lime (SL). An environmental simulation was conducted by emulating sunlight and wet-dry conditions. The powders were collected at consecutive 2-week intervals under sunlight and upon every resuspension. These materials were tested by mixing them with AIV and incubating the mixture for 3 min or 20 h, followed by AIV titration. At the same time, a pH buffering test was conducted by neutralization with Tris-HCl. The results revealed that SSP and SL have high alkalinity and excellent ability to inactivate AIV. In a simulated harsh environment, SSP and SL retained a satisfactory ability to inactivate AIV within 20 h throughout the experimental procedure. However, SSP was able to inactivate AIV during a short contact period (3 min), even under harsh conditions, and it was more resistant than SL to neutralization.