HMOX1 and infection: Our data comparing well-nourished mice, provided a nutrient-rich diet containing similar components to a standard diet commonly used in laboratories, to malnourished animals, fed on a polynutrient deficient diet, infected via needle or sand fly bites, show that vector-initiated infections produce a strong and sustained inflammatory response characterized by an early influx of IL-1β-secreting neutrophils, high expression of HO-1, and enhanced early parasite dissemination from the skin to the spleen, supporting previous findings14,16.