"Impact of the interaction among DENV, ZIKV, and CHIKV on disease dynamics"
Aedes aegypti and Aedes albopictus mosquitoes are the causative agents of dengue (DENV), chikungunya (CHIKV), and Zika (ZIKV) virus infections in humans. The co-circulation of at least two viruses/serotypes, which is common in countries worldwide, such as Columbia and Brazil in Latin America, can cause potential interactions among the viruses/serotypes and misdiagnosis in the lack of adequate laboratory tests due to similar clinical symptoms among their disease courses. We generalized a deterministic compartmental model to analyze how each disease dynamics changes under the potential antagonistic or synergistic interaction among the viruses/serotypes. Our simulation studies showed that under no DENV vaccine, vector control, and interaction among the viruses/serotypes, the peak of the incidence rates for people with no prior infections happens earlier than those cases with one or two prior infections, mostly because the proportion of fully susceptible people is larger than people with at least one prior infection. We observed higher incidence rates for single/multi infections and an earlier peak of the epidemics for single infections when a prior infection by a virus such as ZIKA causes synergistic cross-immunity against CHIKV and DENV serotypes, compared to the situation when it causes antagonistic cross-immunity. Identification of the cross-immunity is not possible when susceptibility statuses of the population are unknown because the high/low incidence rates could be either the results of high/low baseline transmission rates or antagonistic/synergistic interaction effects among the viruses.
Additional authors: Alex Perkins, Department of Biological Science, University of Notre Dame