The Delay in the Licensing of Protozoal Vaccines: A Comparative History.

摘要: Although viruses and bacteria have been known as agents of diseases since 1546, 250 years went by until the first vaccines against these pathogens were developed (1796 1800s). In contrast, Malaria, which is a protozoan-neglected disease, has 5th century BCE and, despite 2,500 having passed then, no human vaccine yet licensed for Malaria. Additionally, modern currently Visceral or Cutaneous leishmaniasis. Vaccination Malaria evolved from inoculation irradiated sporozoites through bite Anopheles mosquitoes in 1930's, failed to give protection, use controlled infection (CHMI) provoked live Plasmodium falciparum curtailed with specific chemotherapy 1940's. CHMI vaccination was relatively efficacious, it some ethical limitations substituted injected recombinant expressing main antigens parasite cycle, starting 1980. Pre-erythrocytic (PEV), Blood stage (BSV), transmission-blocking (TBV), antitoxic (AT), pregnancy-associated are under development. Currently, RTS,S-PEV vaccine, based on circumsporozoite protein, only one that arrived at Phase III trial stage. The "R" stands central repeat region (P.) protein (CSP); "T" T-cell epitopes CSP; "S" hepatitis B surface antigen (HBsAg). Africa, this latter achieved 36.7% efficacy (VE) 5-7 old children associated an increase clinical cases assay. Therefore, spite 35 research, there more progress regarding prevention leishmaniasis also started vaccines. For reasons, second-generation subunit DNA humans Uzbekistan, four veterinary visceral leishmaniasis: Leishmune® (76-80% VE) CaniLeish® (68.4% VE), protection strong endpoints (severe disease deaths natural conditions), less severe (parasitologically PCR-positive cases), Leishtec® 71.4% VE low infective pressure area but 35.7% transient high area, while Letifend® promoted 72% VE. A Nucleoside hydrolase NH36 Leishmania (L.) donovani, sterol 24-c-methyltransferase (SMT) L. infantum reached I phase not disease. This review describes history development focused formulations used preventive medicine. Special attention given delay licensing Protozoan infections, show incidence worldwide still remain threats Public Health.