Chaotic desynchronization of multistrain diseases

Ira Schwartz, US Naval Research Labratory
Leah Shaw, US Naval Research Labratory
Derek Cummings, Johns Hopkins Bloomberg School of Public Health
Lora Billings, Montclair State University
Marie McCrary, Montclair State University
Donald Burke, Montclair State University


Multistrain diseases are diseases that consist of several strains, or serotypes. The serotypes may interact by antibody-dependent enhancement ADE, in which infection with a single serotype is asymptomatic, but infection with a second serotype leads to serious illness accompanied by greater infectivity. It has been observed from serotype data of dengue hemorrhagic fever that outbreaks of the four serotypes occur asynchronously. Both autonomous and seasonally driven outbreaks were studied in a model containing ADE. For sufficiently small ADE, the number of infectives of each serotype synchronizes, with outbreaks occurring in phase. When the ADE increases past a threshold, the system becomes chaotic, and infectives of each serotype desynchronize. However, certain groupings of the primary and secondary infectives remain synchronized even in the chaotic regime.