Respiratory pathogens are microorganisms, such as bacteria and viruses, that can cause infections in the respiratory system. Common examples include influenza virus, Streptococcus pneumoniae, and SARS-CoV-2. These pathogens can lead to illnesses ranging from mild colds to severe pneumonia, affecting the lungs and airways. Transmission of respiratory pathogens often occurs through droplets when an infected person coughs or sneezes. They can also spread by touching contaminated surfaces and then touching the face. Preventive measures include good hygiene practices, such as handwashing and vaccination, to reduce the risk of infection.