Abstract
INTRODUCTION: Asthma is driven by an inflammatory response against normally harmless environmental inorganic and organic compounds in the respiratory tract. Immune responses to airborne pathogens such as viruses and bacteria may reduce the allergic responses but are also known to trigger asthma attacks and eventually lead to severe disease condition. OBJECTIVE: To investigate the role of respiratory pathogens concerning the induction or protection against acute or chronic asthma manifestations. METHODS: We included 131 articles for the final review according to their relevance with the subject. RESULTS: There is apparently contradictory interaction of respiratory germs in the airways of asthmatics which may be protective on one angle but deleterious on the other. CONCLUSION: The relationship between inflammation and remodeling and the pathogenic role of viral and bacterial infection in the airways of asthmatic patients is still highly debatable and incompletely understood.