Eilat virus is used as platform for Chikungunya vaccine

Dr. Scott Weaver says the vaccine offers effective, safe and accessible protection, besides establishing fundamentals for the use of insect-specific viruses as vaccine vectors


Results are promising, since the most recent reports show the chikungunya virus can be harsher than the dengue and zika viruses

Researchers in Texas have announced the development of the first chikungunya fever vaccine made with an insect-specific virus, which they hope will now be evaluated in clinical trials. During the laboratory tests, the vaccine developed a strong immune defense very quickly and completely protected mice and non-human primates from the disease when exposed to the chikungunya virus, Interviewed by the Brazilian Society of Tropical (BSTM) Medicine press advisory, Scott Weaver, Professor and Director of the Institute for Human Infections and Immunity at the University of Texas Medical Branch (UTMB) and lead researcher engaged in the project, explained that based on the efficacy demonstrated in these animals and in extremely strict tests it was subjected to (intracranial inoculation of infant interferon-defective mice), they are very optimistic the vaccine will perform well in humans. The U.S. National Institutes of Health has issued a contract to a company that specializes in vaccine development to begin formulating a plan to further develop the EILV/CHIKV vaccine, he said.

Doctor Scott says this is an unusual, serendipitous project that began with the finding of the first insect-specific alphavirus (unable to infect vertebrates). We had been making chimeras between typical alphaviruses as live-attenuated vaccines for several years, so we already knew how to do the genetic engineering. Our initial thought was that the EILV/CHIKV might remain incapable of infecting vertebrate cells, and thus serve as a pseudo-inactivated vaccine that would be slightly more immunogenic than a formalin-inactivated vaccine because there would be no antigenic degradation that typically accompanies formalin treatment. However, we were surprised to see that the immunogenicity was much better than we would expect from an inactivated vaccine, and that EILV/CHIKV replicated to exceptionally high titers in mosquito cells, allowing us to use large doses, he details.

Still according to the researcher, one of the greatest challenges launching a CHIKV vaccine in the market is the diseases often unrecognized and sporadic nature and an uncertain future of outbreaks. However, since the disease still affects many people in South America (especially Brazil) and Asia (recently in India and Pakistan) with a major burden on public health and with economic impacts from chronic disabilities, there is hope some major pharmaceutical manufacturer might, perhaps encouraged by governments with international assistance, may make the required investment.…