Can UVA radiation have a germicidal effect?

Abstract

This study examines the efficiency of UVA radiation in the eradication of murine mites. The experiment consisted of the radiation of female BALBc mice in a solarium by UVA rays, up to total dosages of 7800 J/cm2 and 12 500 J/cm2. A total of 88 animals were divided into four experimental and three control groups. Animals from the experimental and two control groups were shaved, and animals in two experimental groups were treated by a photoprotective cream half an hour before exposure. The animals in the third control group were not shaven. The presence of mites was detected in histological preparations of most of the animals in the control groups. When compared to the experimental groups of animals exposed to radiation up to 7800 J/cm2, the presence of mites was significantly more frequent in the control group of shaven animals (p = 0.013) and unshaven animals (p < 0.001). When compared to the experimental groups exposed to radiation up to 12 500 J/cm2, the presence of mites was significantly more frequent in the control group of shaven animals (p < 0.001) and unshaven animals (p < 0.001). Median value of mites was statistically much higher in the control, unshaven group of animals in comparison to the untreated group of animals exposed to radiation up to 7800 J/cm2 (p = 0.006). Median value of mites between untreated group of animals exposed to radiation up to 7800 J/cm2 and their shaven control group was near a statistically significant difference (p = 0.056). By comparing the number of mites between the control groups of animals, no presence of statistically significant difference (p = 0.901) was confirmed. UVA radiation led to the effective eradication of murine mites.