Epitope containing short peptides capture distinct IgG serodynamics that enable DIVA for live-attenuated vaccines

Abstract

Differentiating infected from vaccinated animals (DIVA) strategies have been central enabling techniques in several successful viral disease elimination programs. However, owing to their long and uncertain development process, no DIVA-compatible vaccines are available for many important diseases. We report herein a new DIVA strategy based on hybrid protein-peptide microarrays which can theoretically work with any vaccine. Leading from our findings from Peste des petits ruminants (PPR), we found 4 epitope containing short peptides (ECSPs) which have distinct IgG serodynamics: anti-ECSP IgGs only exist for 10-60 days post vaccination (dpv), while anti-protein IgGs remained at high levels for >1000 dpv. These data enabled design of a DIVA diagnostic microarray containing 4 ECSPs and 3 proteins, which unlike cELISA and VNT, enables ongoing monitoring of serological differences between vaccinated individuals and individuals exposed to the pathogen. For 50 samples after 60 dpv, 20 animals were detected with positive anti-ECSP IgGs, indicating recent infections in vaccinated goat/sheep herds. These DIVA diagnostic microarrays will almost certainly facilitate eradication programs for (re-)emerging pathogens and zoonoses.