The Effect of Sun Radiation on the Course of Cutaneous Leishmaniasis in BALB/c Mice

Objective(s) Studies have described immunomedulatory effects of sun exposure and ultraviolet radiation on infectious and neoplastic diseases. Here the effect of exposure to low potency radiation of sun on the course of leishmaniasis in mice was studied. Materials and Methods Fifteen BALB/c mice were exposed to suberythemogenic doses of sun (mean 180 mJ/cm2/day of UVB) 2 months before and 4 months after Leishmania major inoculation to food pad. Control group was kept in the sun protected environment. From 2nd to 17th week after inoculation, size of the lesion was recorded in each group weekly and at last week the parasite burden in spleen was detected. Results were compared between two groups. Results Seven mice from case group and 9 mice from control group survived up to last week. The mean lesion size was 0.90±0.59 cm in exposed and 4.01±3.59 cm in unexposed mice (P= 0.037). Parasite burden in spleen of case and control groups were 5.5±4.61 and 106.94±279.76 respectively (P= 0.006). Conclusion Chronic exposure of BALB/c mice to suberythemogenic doses of sun suppressed skin lesion and decreased the extension of L. major to spleen.