ACIP Updates Guidelines for Prevention and Control of Influenza With Vaccines

August 3, 2010 — The US Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) has issued new 2010 recommendations for prevention and control of influenza with vaccines, according to guidelines reported early release in the July 29 issue of Morbidity and Mortality Weekly Report. This report updates the 2009 ACIP recommendations concerning the use of influenza vaccine for influenza prevention and control.
The report also describes a US Food and Drug Administration labeling change for Afluria (CSL Biotherapies) influenza virus vaccine to reflect the risk for fever and febrile seizure.
"Influenza A subtypes that are generated by a major genetic reassortment (i.e., antigenic shift) or that are substantially different from viruses that have caused infections over the previous several decades have the potential to cause a pandemic," write Anthony E. Fiore, MD, from the Influenza Division, National Center for Immunization and Respiratory Diseases, CDC, Atlanta, Georgia, and colleagues.
"In April 2009, a novel influenza A (H1N1) virus, 2009 influenza A (H1N1), that is similar to but genetically and antigenically distinct from influenza A (H1N1) viruses previously identified in swine, was determined to be the cause of respiratory illnesses that spread across North America and were identified in many areas of the world by May 2009. Influenza morbidity caused by 2009 pandemic influenza A (H1N1) remained above seasonal baselines throughout spring and summer 2009 and was the cause of the first pandemic since 1968."
Highlights of 2010 Guidelines
The 2010 guidelines emphasize the following:

• All persons at least 6 months old should receive annual vaccination for the 2010-2011 influenza season;
• During the 2010-2011 season, 2 doses of a 2010-2011 seasonal influenza vaccine should be given at a minimal interval of 4 weeks to children aged 6 months to 8 years with unknown vaccination status who have never received seasonal influenza vaccine before (or who received seasonal vaccine for the first time in 2009-2010 but received only 1 dose in their first year of vaccination), as well as to children who did not receive at least 1 dose of an influenza A (H1N1) 2009 monovalent vaccine regardless of previous influenza vaccine history;
• Vaccines should contain the 2010-2011 trivalent vaccine virus strains A/California/7/2009 (H1N1)-like (the same strain as was used for 2009 H1N1 monovalent vaccines), A/Perth/16/2009 (H3N2)-like, and B/Brisbane/60/2008-like antigens;
• The report describes Fluzone High-Dose (sanofi pasteur), a newly approved vaccine for persons at least 65 years old; and
• The report also provides information about other newly approved, standard-dose influenza vaccines and expanded age indications for previously approved vaccines.

The updated guidelines recommend starting vaccination efforts as soon as the 2010-2011 seasonal influenza vaccine is available and continuing throughout the influenza season, and they also provide a summary of safety data for US-licensed influenza vaccines. During the 2010-2011 influenza season, vaccination and healthcare providers should check CDC's influenza Web site for any updates or supplements that might be needed to these recommendations, as well as for recommendations for influenza diagnosis and antiviral use published before the start of the 2010-2011 influenza season.
Recommendations for 2010
A summary of recommendations for influenza vaccination for 2010 is as follows:

• Annual vaccination is recommended for all persons aged 6 months or older.
• As providers and programs make the transition to routine vaccination of all persons aged 6 months or older, a focus of vaccination efforts should continue to be protection of persons at higher risk for influenza-related complications.
• When vaccine supply is limited, vaccination efforts should prioritize persons who:   
  • Are aged 6 to 59 months or at least 50 years;
  • Have chronic pulmonary (including asthma), cardiovascular (except hypertension), renal, hepatic, neurologic, hematologic, or metabolic disorders (including diabetes mellitus);
  • Have disorders of immunosuppression, including those caused by medications or by HIV);
  • Are or will be pregnant during the influenza season;
  • Might be at risk for Reye's syndrome after influenza virus infection because they are aged 6 months to 18 years and are receiving long-term aspirin therapy;
  • Are residents of nursing homes and other long-term care facilities; American Indians/Alaska Natives; morbidly obese (body mass index ≥ 40 kg/m²); and/or healthcare personnel;
  • Are household contacts and caregivers of persons with medical conditions putting them at greater risk for severe complications from influenza, or of children younger than 5 years and adults 50 years or older. The guidelines particularly emphasize vaccinating contacts of children younger than 6 months.

"Emphasis on providing routine vaccination annually to certain groups at higher risk for influenza infection or complications is advised, including all children aged 6 months–18 years, all persons aged ≥50 years, and other persons at risk for medical complications from influenza," the authors of the report write. "Despite a recommendation for vaccination for approximately 85% of the U.S. population over the past two seasons, <50% of the U.S. population received a seasonal influenza vaccination in 2008–09 or 2009–10. Estimated vaccine coverage for the 2009 H1N1 monovalent vaccine coverage was <40%."
MMWR Morb Mortal Wkly Rep. July 29, 2010;59(Early Release);1-62.