Commentary on the Issue of Leishmania Infection: Focus on Some Pathogenetic, Clinical, and Epidemiological Aspects

Leishmaniasis are infectious diseases caused by several parasitic species of Leishmania, mainly transmitted by the bite of infected phlebotomine sandflies. Humans, dogs, rodents, and other domestic and wild animals can act as reservoir hosts for the different Leishmania species. It is a neglected tropical disease that is endemic in Asia, the Middle East, North and East Africa, the Mediterranean region, and South and Central America. Clinical manifestations and disease severity depend on the species of the infecting parasites and the immunity status of the host. Leishmania represses the protective host immune response by manipulating the macrophage function, subverting cytokine expression to favor its survival and dissemination. A balance between pro-inflammatory and regulatory cells is necessary to bring a positive outcome. Accurate diagnosis and effective treatment represent the cornerstone in the control of this disease, although these are difficult in an environment of precariousness and poverty. Some recent studies highlighted the progressing work on diagnosis and treatments, such as the development of new benzimidazole-triazole derivatives for blocking the parasite growth, feline leishmaniasis with a comparison of immune responses in cats and dogs, and a transglutaminase that has been purified from L. infantum. The results of these studies could open new avenues in combating leishmaniasis.