The clinical spectrum of influenza ranges from asymptomatic infection to primary viral pneumonia that may progress to death.
Patients presenting with influenza-like illness (ie temperature of 37.8ºC, cough and/or sore throat and absence of a known cause other than influenza) might be infected with different types of influenza virus [eg avian influenza (H5N1)] as well as other respiratory pathogens.
A high index of suspicion is needed to recognize influenza in hospitalized patients.
Pneumonia is the most common complication of influenza virus.
The prevalence of allergic diseases in the Asia-Pacific region is expected to rise over the next 20 years, driven by rapid economic development and urbanization. Allergic diseases have high socioeconomic impact by impairing productivity and quality of life, and the impact may be greater in Asia-Pacific than in Europe due to the presence and predominance of perennial allergens.