Diseases produced by protozoan parasites are one of the main causes of morbidity and mortality around the world, affecting millions of people and domestic animals. Among these diseases, leishmaniasis has become the second most common cause of death, with a very significant (42-fold) increment during the past twenty years. Due to unavailability of vaccines, failures of insecticides to control vector, measures are solely dependent upon chemotherapy. The emergence of drug resistance against presently available leishmaniasis drugs has deteriorated the situation.Unfortunately, limited information...

Fungi are eukaryotic microorganisms that are closely related to humans at cellular level. Human fungal pathogens belong to various classes of fungi, mainly zygo- cetes, ascomycetes, basidiomycetes, and deuteromycetes. In recent years, fungal infections have dramatically increased as a result of improved diagnosis, high frequency of catheterization, instrumentation, etc. However, the main cause remains the increasing number of immunosuppressed patients, mostly because of HIV infection and indiscriminate usage of antineoplastic and immunosuppressive agents, broad-spectrum antibiotics and...