Partial cross-enhancement in models for dengue epidemiology

Area of Science:

• Epidemiology
• Virology
• Mathematical Modeling

Background:

• Four dengue virus serotypes coexist globally, leading to complex immune responses.
• Antibody-dependent enhancement (ADE) of secondary infections is linked to severe dengue hemorrhagic fever.
• Existing models often assume universal ADE in secondary infections.

Purpose of the Study:

• To develop a novel modeling framework differentiating between enhanced and cross-protected secondary dengue infections.
• To reassess the role of ADE in driving epidemiological oscillations in dengue models.
• To investigate how ADE modifies the impact of other drivers in dengue transmission.

Main Methods:

• Introduced a compartmental model stratifying the susceptible population into those prone to enhancement and those with cross-protection.
• Applied the new framework to analyze established dengue models exhibiting multi-annual oscillations.
• Evaluated the contribution of ADE to disease severity and epidemic patterns.

Main Results:

• Empirical data indicate that only a subset of secondary dengue infections exhibit enhancement.
• The proposed model distinguishes between populations with enhanced susceptibility and those with cross-protection.
• Findings suggest ADE is unlikely to be the primary driver of multi-annual dengue oscillations.

Conclusions:

• Dengue virus secondary infections are not uniformly enhanced; a portion shows cross-protection.
• Enhanced dengue virus infections may modulate, rather than solely drive, epidemiological cycles.
• This nuanced modeling approach improves understanding of dengue hemorrhagic fever pathogenesis and transmission dynamics.