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The involvement of these structures may result in nasal or sinus congestion, and sore throat. Any coughing or sneezing activity may then generate aerosolized particles. Some of the common infections that can spread via airborne transmission include the following:Airborne disease is not exclusive to humans but can also affect non-humans. For example, many types of poultry are often affected by an avian disorder (Newcastle disease), that is also transmitted via an airborne route. However, it is important to understand that exposure to an animal or a patient with an airborne disease does not automatically ensure disease transmission. The infection also depends on the host immunity, how much exposure the individual has suffered and the duration of exposure to the infected patient.[5][9][10][11]Besides patients, there are also several medical and surgical procedures that can generate aerosolized particles. In most cases, these airborne particles are generated during manipulation of the large airways. Examples include:Airborne transmission of microorganisms depends on several physical variables endemic to the infectious particle. Factors that influence the spread of airborne infections includes the following:These factors affect the distance of spread, duration, and infectiousness of droplet particles. For example, the influenza virus is relatively easily spread in the northern hemisphere because of climate conditions that favor infectiousness of the virus but many bacterial infections cannot spread outdoors for most of the year, and thus remain in a state of dormancy.The ultraviolet (UV) rays of the sun are harmful to both bacteria and viruses. The strength and duration of UV light exposure can determine the survival of infectious pathogens; In those parts of the country with a higher average of daily sunshine and those close to the equator, some pathogens lose their infectious ability.However, if the levels of humidity are high, then even in the presence of UV light, the infectious particle can survive for a longer period. It is believed that this is due to the formation of vapor around the aerosolized particles which acts as a barrier to the UV rays.Several studies have shown that after tropical storms, the first quantity of fungal spores is diminished but within a few days, the number of spores will increase exponentially compared to normal environmental conditions.Socioeconomic and living conditions: Like infectious diseases that are spread via contact, the role of living conditions and socioeconomic factors plays a key role in airborne transmission. Dwelling and the number of people residing in one area is an important aspect. The spread of disease is much faster in urban areas compared to rural areas. In urban areas, buildings and other high-rise structures make transmission of bacterial and viral pathogens relatively easy, but in rural areas, airborne particles containing fungal spores are more common.Residing near a source of water such as a lake or river can also be a cause of airborne disease outbreaks, especially after a change in the local watershed.In poor countries, inadequate sewage and drainage systems also increases the risk of formation of airborne particles and spread. Working with certain animals also increases the risk of spread of certain airborne diseases.