Age

Persons six months or older with an underlying medical condition (e.g., cardiac, pulmonary) who are at increased risk for complications of influenza or who required regular medical follow-up or hospitalization during the preceding year (see medical conditions below)

Persons 50 years or older

Any person six months or older to reduce the chance of influenza infection

Occupations

Physicians, nurses and other personnel in hospital and outpatient care settings, including emergency response workers

Employees of health care facilities (e.g., nursing homes, chronic care facilities) who have contact with residents

Persons who provide home care to people in high-risk groups

Medical conditions

Alcoholism and alcoholic cirrhosis

Long-term aspirin therapy in children and teenagers (6 months to 18 years of age) who may be at risk for Reye's syndrome after influenza virus infection

Chronic cardiovascular disorders in adults and children

Hemoglobinopathies

Immunocompromised conditions (e.g., congenital immunodeficiency, malignancy, human immunodeficiency virus infection, organ transplantation, immunosuppressive therapy)*

Chronic metabolic diseases (e.g., diabetes)

Chronic pulmonary diseases, including asthma and chronic obstructive pulmonary disease

Chronic renal dysfunction

Pregnancy beyond 14 weeks of gestation during the influenza season

Pregnancy in women with medical conditions that increase their risk for complications from influenza, regardless of trimester

Persons who can transmit influenza to high-risk individuals

Household members (including children) in close contact with persons who are at high risk for influenza

Residents of nursing homes and other chronic care facilities, regardless of age, who have chronic medical conditions