Key Point:

New influenza prevention and control guidelines from the CDC’s Advisory Committee on Immunization Practices include four important new recommendations regarding the composition and use of the influenza vaccine.

Harper, MD, lead author of the guidelines, told Pulmonary Reviews. “This is necessary because infants and small children have rates of hospitalization for influenza that are as high as those among the elderly,” explained Dr. Harper, Medical Officer in the National Center for Infectious Diseases at the CDC.

Exposure to the live, attenuated influenza vaccine is dangerous for immunosuppressed patients, and thus they should be given only the inactivated vaccine. However, it is important to note that when such patients require care in a protected environment, they should not come into close contact with anyone—family member, friend, or health care worker—who has received the live-virus vaccine. A health care worker who receives a live-virus influenza vaccine should refrain from contact with severely immunosuppressed patients for seven days after vaccination, the guidelines state.

In addition, the live-virus vaccine is inappropriate for children younger than 5 years; adults 50 or older; pregnant women; children or adolescents who are receiving aspirin or other salicylates; patients with asthma, diabetes, renal dysfunction, or other underlying medical conditions; and patients with a history of Guillain-Barré syndrome. However, the inactivated vaccine can be administered to these groups. “The ACIP recommends that vaccination with inactivated vaccine can take place in any trimester, though safety data are limited,” Dr. Harper noted. In fact, vaccination is recommended for pregnant women because they are at increased risk for flu-related infections.

The live-virus vaccine is appropriate for healthy persons between the ages of 5 and 49. Advantages of this vaccine include ease of administration and its potential to induce a broad mucosal and systemic immune response. Many people may find the intranasal route more acceptable than the traditional intramuscular injection, which may help increase vaccination rates.

The inactivated and live-virus vaccines being manufactured for the 2004/2005 influenza season include three antigens that are representative of the influenza viruses likely to be in circulation at that time—A/Fujian/411/2002 (H3N2)–like, A/New Caledonia/20/99 (H1N1)–like, and B/ Shanghai/361/2002–like. As usual, the vaccine supply will be monitored throughout the manufacturing period. Based on the supply, recommendations will be made about the need for tiered timing of vaccination in different groups at risk for influenza infection.

—Timothy Begany

Reference
1. Harper SA, Fukuda K, Uyeki TM, et al; Centers for Disease Control and Prevention. Prevention and control of influenza: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2004;53(RR-6):1-40.