Bengaluru: A recent study conducted by the Indian Institute of Science (IISc) has revealed notable differences in how weather conditions impact the survival of harmful bacteria on surfaces. The research, published in the Journal of Colloid and Interface Science, highlights that the common pathogen Pseudomonas aeruginosa can endure up to five times longer in humid, cool conditions compared to hot, dry environments.
The investigation focused on the behaviour of simulated respiratory droplets containing Pseudomonas aeruginosa on glass surfaces under various temperature and humidity levels. Key findings indicate that in environments with cooler temperatures and higher humidity (25°C, 70% relative humidity), approximately 10% of the bacteria survived after five hours. Conversely, in hotter and drier conditions (31°C, 46% relative humidity), less than 2% of the bacteria persisted. This study underscores the significant impact of humidity on droplet evaporation rates and crystal formation, which in turn affect bacterial survival. One of the crucial discoveries was the role of mucin, a component of respiratory fluids, in protecting bacteria in humid conditions. The lead author of the study stressed the importance of these findings, stating: “Our findings highlight how environmental factors can dramatically influence pathogen persistence on surfaces. This has important implications for infection control, especially in hospitals and public spaces.”
The implications of this research extend beyond mere academic interest. By understanding the environmental factors that affect bacterial longevity, more effective strategies can be developed for controlling the spread of infectious diseases. This knowledge is particularly pertinent for public health policies, especially in regions experiencing varying climatic conditions throughout the year. For instance, hospitals and other healthcare facilities might consider adjusting cleaning protocols and environmental controls based on seasonal changes in temperature and humidity to mitigate the risk of infection. Similarly, public spaces could benefit from tailored disinfection strategies that account for local weather patterns to better protect public health. The research team at IISc believes that these insights can aid in crafting more informed and effective public health policies, ultimately reducing the incidence and spread of infections. As climate patterns shift globally, such studies are increasingly vital for adapting public health strategies to new environmental realities. The findings from this study serve as a reminder of the intricate relationship between environmental conditions and pathogen behaviour, emphasizing the need for adaptive measures in infection control practices across various settings.
