Hazard Characterization of Modified Vaccinia Virus Ankara Vector: What Are the Knowledge Gaps?

Okeke, Malachy I.; Okoli, Arinze S.; Diaz, Diana; Offor, Collins; Oludotun, Taiwo G.; Tryland, Morten; Bøhn, Thomas; Moens, Ugo

The interaction between virus-vectored vaccines and naturally circulating wild-type viruses is essential to ERA since baseline data on the occurrence, nature and geographic distribution of the later is required in order to evaluate the potential for recombination, complementation, reactivation or reversion to wild-type virus. In case of MVA, this will require knowledge of the occurrence, distribution and characteristics of naturally circulating OPVs in locations and ecosystems in which recombinant MVA vaccines are to be deployed, especially for the vaccination of domesticated animals and wildlife. With the exception of Germany [112] [113] [114] [115] [116] , United Kingdom [115, 117, 118] , Fennoscandia [119] [120] [121] [122] [123] [124] , USA [125] [126] [127] [128] , Brazil [129] [130] [131] [132] and India [133] [134] [135] , data on the occurrence and characteristics of wild-type OPVs in remaining regions of the globe are limited or non-existent. MVA-vectored vaccines against malaria [136, 137] , HIV/AIDS [138] , tuberculosis [68] , Middle East respiratory syndrome coronavirus (MERS-CoV) [83] , Ebola [73] and several other human and animal diseases [26, 86] are in trials in Africa, Asia and Middle East, but knowledge of the characteristics and reservoir animal species for wild-type OPVs in these regions are largely non-existent. Consequently, no scientifically valid inference can be made on the potential of virus-virus interactions between recombinant MVA vaccines and naturally occurring virus relatives in these regions.