An improved understanding of the underlying physicochemical properties of respiratory aerosol that influence viral infectivity may open new avenues to mitigate the transmission of respiratory diseases such as COVID-19. Previous studies have shown that an increase in the pH of respiratory aerosols following generation due to changes in the gas-particle partitioning of pH buffering bicarbonate ions and carbon dioxide is a significant factor in reducing SARS-CoV-2 infectivity. We show here that a significant increase in SARS-CoV-2 aerostability results from a moderate increase in the atmospheric carbon dioxide concentration (e.g. 800 ppm), an effect that is more marked than that observed for changes in relative humidity. We model the likelihood of COVID-19 transmission on the ambient concentration of CO₂, concluding that even this moderate increase in CO₂ concentration results in a significant increase in overall risk. These observations confirm the critical importance of ventilation and maintaining low CO₂ concentrations in indoor environments for mitigating disease transmission. Moreover, the correlation of increased CO₂ concentration with viral aerostability need to be better understood when considering the consequences of increases in ambient CO₂ levels in our atmosphere.

更好地了解影响病毒传染性的呼吸气溶胶的基本理化特性可能会为减轻 COVID-19 等呼吸道疾病的传播开辟新途径。先前的研究表明，由于缓冲碳酸氢根离子和二氧化碳的 pH 值气体颗粒分配的变化，产生后的呼吸气溶胶 pH 值升高是降低 SARS-CoV-2 传染性的重要因素。我们在此表明​​，大气二氧化碳浓度（例如 800 ppm）的适度增加导致 SARS-CoV-2 气稳定性显着增加，这种影响比相对湿度变化观察到的影响更为明显。我们根据环境 CO ₂浓度对 COVID-19 传播的可能性进行了建模，得出的结论是，即使 CO ₂浓度适度增加，也会导致总体风险显着增加。这些观察结果证实了室内环境中通风和保持低CO ₂浓度对于减轻疾病传播的至关重要性。此外，在考虑大气中环境 CO ₂水平增加的后果时，需要更好地理解CO ₂浓度增加与病毒气稳定性的相关性。