Structural stability of SARS-CoV-2 degrades with temperature

Area of Science:

• Virology
• Biophysics
• Epidemiology

Background:

• The COVID-19 pandemic, caused by SARS-CoV-2, has had significant global impacts.
• Understanding SARS-CoV-2 transmission dynamics, including seasonality, is crucial for public health policy.
• Previous research suggests coronaviruses exhibit seasonal patterns, with increased winter transmission, but the underlying mechanisms remain unclear.

Approach:

• Utilized atomic force microscopy (AFM) to investigate the structural stability of individual SARS-CoV-2 virus-like particles.
• Examined the effects of varying temperatures, including mild elevations consistent with seasonal warming, on viral particle integrity.
• Assessed viral stability in both liquid droplet and dried states.

Key Points:

• Atomic force microscopy revealed that even slight temperature increases significantly disrupt the structural stability of SARS-CoV-2 virus-like particles.
• This destabilization effect is particularly pronounced when viral particles are in a dried state compared to liquid droplets.
• The findings provide a mechanistic, single-particle perspective on viral stability and its temperature dependence.

Conclusions:

• The temperature-dependent structural destabilization of SARS-CoV-2 particles offers a potential explanation for observed viral seasonality.
• This research supports the hypothesis that warmer temperatures contribute to reduced viral infectivity, consistent with non-mechanistic studies.
• The results strengthen the scientific basis for expecting a resurgence of COVID-19 cases during winter months.