ART4 and Ebola hemorrhagic fever: Glycoprotein-specific antibodies elicited by adenovirus 5 and chimpanzee adenovirus 3-vectored vaccines constitute a non-mechanistic correlate of protection against otherwise lethal Ebola virus challenge to NHPs,5, 9, 16 although T cells seem key in mediation of protection conferred by adenovirus-vectored and DNA Ebola vaccines.5, 17 Of NHPs immunised with adenovirus 5-vectored Ebola vaccine and challenged about 1 month later,5, 9 animals that attained reciprocal titres of 1000 or higher (with use of ELISA as described by Sullivan and colleagues5) showed 77% vaccine efficacy against death.