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Purpose: The temporal and spatial formation of the temperature field and its changes during/upon water-filtered infrared-A (wIRA)-irradiation in porcine skin and subcutis were investigated in vivo in order to get a detailed physical basis for thermotherapy of superficial tumors and infections caused by thermosensitive microbial pathogens (e.g., Mycobacterium ulcerans causing Buruli ulcer). Methods: Local wIRA-hyperthermia was performed in 11 anesthetized piglets using 85.0 mW cm-2, 103.2 mW cm-2 and 126.5 mW cm-2, respectively. Invasive temperature measurements were carried out simultaneously in 1-min intervals using eight fiber-optical probes at different tissue depths between 2 and 20 mm, and by an IR thermometer at the skin surface. Results: Tissue temperature distribution depended on incident irradiance, exposure time, tissue depths and individual 'physiologies' of the animals. Temperature maxima were found at depths between 4 and 7 mm, exceeding skin surface temperatures by about 1-2 K. Tissue temperatures above 37 °C, necessary to eradicate M. ulcerans at depths <20 mm, were reached reliably. Conclusions: wIRA-hyperthermia may be considered as a novel therapeutic option for treatment of local skin infections caused by thermosensitive pathogens (e.g., in Buruli ulcer). To ensure temperatures required for heat treatment of superficial tumors deeper than 4 mm, the incident irradiance needed can be controlled either by (a) invasive temperature measurements or (b) control of skin surface temperature and considering possible temperature increases up to 1-2 K in underlying tissue.

Fluoroquinolones (FQ) undergo minimal metabolization in animals and are excreted via faeces and urine, where they enter the environment almost unchanged. In this study we investigated the presence of quinolone-resistant Escherichia coli (E. coli) in the environment of 65 farms of a sow pool system in Switzerland. Two hundred and seventy-nine samples from liquid manure and wipes of dust and pen walls were collected and the use of FQ on the farms was investigated. From 45% of dust samples, 52% of pen wall samples and 69% of liquid manure samples quinolone-resistant E. coli (QRE) were cultivated. Significant higher counts of quinolone-resistant colonies were found in liquid manure samples than in dust (p < 0.01) or pen wall samples (p < 0.05). Samples from breeding farms were significantly more often positive than samples from fattening farms (p < 0.01). Samples taken from farms using FQ were significantly more frequently positive for QRE than samples from farms without FQ usage (p < 0.01). On 97% of the farms with FQ use and 85% (23/27) of the farms without FQ use QRE could be found in at least one sample (no significant difference). Overall, QRE were widespread in the environment of the investigated pig farms.