Influenza A virus and related secondary bacterial infections

Background and Aim : Influenza infection is considered to be a serious respiratory disease inhumans. Annually, epidemics or even pandemics give rise to the frequent antigenetic variations ofvirus surface receptors, throughout the world. Bacterial infections followed by influenza are thebiggest medical concerns associated with elevated mortality rates. These high morbidity andmortality rates have become a priority in terms of health. Likewise, the economic aspects of theissue have special importance also.Methods : In the present study, several articles have been investigated with regard to mainkeywords including influenza A, secondary bacterial infections and pandemics. Then, attemptshave been made to summarize the information.Results : Until this date, a number of influenza pandemics have taken place with varying morbidityand mortality rates because of secondary bacterial infections followed by influenza. However, the۱۹۱۸ pandemic had the highest death rate recorded. According to investigative studies,Streptococcus pneumoniae and Staphylococcus aureus are the most common isolated bacteria inpatients with secondary infections. Other bacteria, such as Haemophilus influenza, Streptococcuspyogenes, and to a lesser degree Legionella spp., are involved in these infections as well.Conclusion : Currently, it is known that various protease enzymes intensify the influenza virusinfectivity. Another important aspect of influenza occurs in the Hajj pilgrimage season and manyvaccines have been made to deal with its consequences. These vaccines decrement the mortalityrate, however, some have minor side effects.

کلیدواژه ها:

Influenza Virus ، Secondary bacterial infection ، Pandemics