The following priority groups should be vaccinated for influenza:

• persons aged > 65 years with comorbid conditions
• residents of long term care facilities
• persons aged 2 to 64 years with comorbid conditions
• persons aged > 65 years without comorbid conditions
• children aged 6 to 23 months
• pregnant women
• health-care personnel who provide direct patient care
• household contacts and out-of-home caregivers of children aged < 6 months

A change to this year’s recommendations is that comorbid conditions now specifically includes persons with any condition (e.g., cognitive dysfunction, spinal cord injuries, seizure disorders, or other neuromuscular disorders) that can compromise respiratory function or the handling of respiratory secretions or that can increase the risk for aspiration.

CDC has specified that, beginning October 24, flu vaccine can be offered to anyone, whether or not they are in one of these high-risk groups.

Inactivated Trivalent Influenza Vaccine (TIV)
Dosage recommendations for inactivated trivalent influenza vaccine (TIV) vary according to age group. For previously unvaccinated children aged < 9 years, 2 doses administered > 1 month apart are recommended. When possible, the second dose should be administered before December. If a child aged < 9 years receives vaccine for the first time one season and does not receive the second dose that season, only 1 dose of vaccine should be administered the following season. Inactivated influenza vaccine should not be administered to persons known to have anaphylactic hypersensitivity to eggs or to other components of the influenza vaccine without first consulting a physician.

Live, Attenuated Influenza Vaccine (LAIV)
For healthy persons aged 5 to 49 years of age, LAIV is a good option for influenza vaccination, including for persons in close contact with groups at high risk for influenza complications and most health-care workers. Possible advantages of LAIV include its potential to induce a broad mucosal and systemic immune response, its ease of administration, and the acceptability of an intranasal rather than intramuscular route of administration.

The following populations should not be vaccinated with LAIV:

• persons aged < 5 years or those aged > 50 years;
• persons with asthma, reactive airway disease or other chronic disorders of the pulmonary or cardiovascular systems; persons with other underlying medical conditions, including such metabolic diseases as diabetes, renal dysfunction, and hemoglobinopathies; or persons with known or suspected immunodeficiency diseases or who are receiving immunosuppressive therapies;
• children or adolescents receiving aspirin or other salicylates (because of the association of Reye syndrome with wild-type influenza infection);
• persons with a history of Guillain Barré Syndrome;
• pregnant women; or
• persons with a history of hypersensitivity, including anaphylaxis, to any of the components of LAIV or to eggs.

Severely Immunosuppressed Patients and Their Contacts
Inactivated influenza vaccine is preferred for vaccinating household members, health-care workers, and others who have close contact with severely immunosuppressed persons (e.g., patients with hematopoietic stem cell transplants) during those periods in which the immunosuppressed person requires care in a protective environment. Health-care workers who receive LAIV should refrain from contact with severely immunosup-pressed patients for 7 days after vaccine receipt. Hospital visitors who have received LAIV should also refrain from contact with severely immunosuppressed persons for 7 days after vaccination; however, such persons need not be excluded from visitation of patients who are not severely immunosuppressed.

Severely immunosuppressed persons should not administer LAIV. However, other persons at high risk for influenza complications, including persons with underlying medical conditions placing them at high risk or who are likely to be at risk, including pregnant women, persons with asthma, and persons aged > 50 years may administer LAIV

Children aged 5–8 years previously unvaccinated at any time with either LAIV or inactivated influenza vaccine should receive 2 doses of LAIV separated by at least 6 weeks. Children aged 5 to 8 years previously vaccinated at any time with either LAIV or inactivated influenza vaccine should receive 1 dose of LAIV and they do not require a second dose. Persons aged 9 to 49 years should receive 1 dose of LAIV. In accordance with CDC general recommendations on immunization, live vaccines, (i.e., MMR, varicella, LAIV), not administered on the same day should be administered at least 4 weeks apart.