A potential cure for ebola hemorrhagic fever

Ebola hemorrhagic fever is considered to be one the most deadly viral diseases, with fatality rates of up to 90%. In 2014, a new strain of the Ebola virus emerged in a few countries in West Africa. The outbreak was the most deadly since the discovery of the virus. The pathophysiology of the disease begins with fever and flu-like symptoms that occur when phagocytic cells encounter the virus and release an excess of cytokines. In the terminal stages of the disease, the virus infects endothelial cells compromising them completely and eventually leading to hypovolemic shock. As of August 2014, there is no vaccine for the virus, but over the past decade, several experimental drugs have shown promise in treating Ebola. The most successful ones use monoclonal antibody (mAb) mixtures, two of which, MB-003 and ZMAb, have shown very promising results. Recently, a group of scientists performed a trial using optimized mixtures that combined the best components of MB-003 and ZMAb. These cocktails are called Zmapp1 and Zmapp2. The experiment consisted of challenging Rhesus macaques with the Ebola virus. These macaques were divided in three groups: treatment with ZMapp1 (Group A), treatment with ZMapp2 (Group B), and control group that was given just the non-specific adjuvants (chemical that are added to boost the immune response) but no monoclonal antibodies (Group C). Drugs were administered on days 3, 6, and 9 after the infection with the virus, and survival rates of each group are shown in Figure 1.

Figure 1: Survival rate of Rhesus macaques after infection with Ebola virus in 3 experimental groups.

Adapted from : Qiu et al. 2014. Reversion of advanced Ebola virus disease in nonhuman primates with ZMapp. Nature doi:10.1038/nature13777