Characteristics of seasonal influenza vaccine use among the nine Southeast Asian countries that responded to study survey.

*Due to chronic metabolic diseases (including diabetes mellitus), renal dysfunction, haemoglobinopathies or immunosuppression (including by medication or HIV).†High risk conditions: Malaysia (chronic cardiovascular, pulmonary, metabolic or renal disease, or who are immunocompromised); Philippines (chronic pulmonary or cardiovascular disorders); Singapore (diseases of the pulmonary or cardiovascular systems, including asthma); Thailand (chronic obstructive pulmonary disease, asthma, heart disease, stroke, kidney failure, cancer, diabetes, thalassemia, immunosuppression including persons infected with HIV); Vietnam (COPD, congenital heart disease, heart failure, diabetes, immunodeficiency).**Only includes elderly with >1 more of the following chronic conditions: chronic cardiovascular, pulmonary, metabolic or renal disease, or who are immunocompromised.