Infected Parasite (IMAGE) Washington University School of Medicine Caption Viral infections appear red in this photo of the parasite Leishmania; the parasites’ nuclei are blue. New evidence published in Science this week suggests that these infections may help Leishmania cause more harm when it infects animal and human hosts. Credit Nicolas Fasel, PhD, Univ. of Lausanne in Switzerland Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.