EPIDEMIOLOGICAL CHARACTERISTICS OF AIRBORNE DROPLET INFECTIONS

Abstract

Airborne droplet infections represent a significant mode of transmission for many respiratory pathogens. These infections occur when respiratory secretions—such as from coughing, sneezing, talking or singing— produce droplets and droplet nuclei that contain infectious agents. The size, evaporation and transport dynamics of these particles are critical in determining their infectious potential. Smaller droplets may evaporate rapidly, forming droplet nuclei that remain suspended in air for extended periods and travel beyond short-range distances, while larger droplets settle quickly. Factors such as indoor airflows, humidity, ventilation, crowding and susceptibility of hosts influence epidemiological characteristics. Key features include rapid person-to-person spread in closed environments, variable incubation periods, and the possibility of asymptomatic or pre-symptomatic transmission. Understanding these dynamics is crucial for preventive measures including masks, ventilation improvements, distancing and hygiene. This review outlines the epidemiological features of airborne droplet infections, describing pathogen sources, modes of transmission, environmental and host factors impacting spread, and implications for control and prevention.