The need to protect patients suffering from COPD against infectious diseases is proved by numerous studies and confirmed by practical health care. Up to 75-80% of COPD exacerbations have an infectious etiology. Furthermore, according to GOLD data, in one third of all cases it is impossible to establish a cause of development of severe COPD exacerbations. According to the data of local authors the frequency of detection of Streptococcus pneumoniae in inflammatory respiratory diseases prevails over the other pathogens. Haemophilus infection is less common, but its persistence in patients with COPD causes a progressive worsening of lung function and reduces the interval of remission. The influenza virus is not a primary risk factor inducing COPD exacerbations in patients, but it contributes to the development of bacterial superinfection, especially S. pneumoniae, H. influenzae and others, which is the cause of death.