Drivers of Infectious Disease Seasonality: Potential Implications for COVID-19

Area of Science:

• Infectious Disease Epidemiology
• Chronobiology
• Environmental Science

Background:

• The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has raised questions about the potential for coronavirus disease 2019 (COVID-19) to become a seasonal disease.
• Many infectious diseases exhibit seasonal patterns influenced by geographical region, timing, and amplitude, similar to endemic human coronaviruses.

Purpose of the Study:

• To explore the potential seasonality of COVID-19 by integrating epidemiological and chronobiological perspectives.
• To identify key drivers of infectious disease seasonality, including environmental, behavioral, and host-related factors.
• To highlight the need for a multidisciplinary approach in predicting and mitigating seasonal infectious diseases.

Main Methods:

• Review of epidemiological evidence on environmental and behavioral drivers of infectious disease seasonality.
• Chronobiological analysis of within-host physiological changes affecting disease susceptibility and morbidity.
• Integration of data from photoperiodic, circannual, and comparative human and animal studies.

Main Results:

• Host immune seasonality is proposed as a significant factor contributing to COVID-19 seasonality, warranting further investigation.
• Environmental and behavioral factors are recognized drivers, but their interplay with host physiology requires deeper study.
• Rapid, human-induced environmental changes complicate the prediction of infectious disease seasonality.

Conclusions:

• A proactive, multidisciplinary approach is essential for predicting, mitigating, and preventing seasonal infectious diseases.
• Host immune seasonality should be evaluated alongside weather and behavior in understanding COVID-19 patterns.
• Further research, including animal models, is needed to fully elucidate the complex drivers of infectious disease seasonality.