Ample vaccine supply key to combatting unpredictability of flu season

The only predictable aspect of the influenza season is its unpredictability, according to experts.

For example, the 2012-2013 influenza season was moderately severe, that started early and lasted longer than a usual influenza season. On the other hand, the 2011-2012 year was a mild influenza year.

“The best way to be prepared for the upcoming influenza season is to ensure that there is an ample vaccine supply, it is available early and throughout the season, that influenza vaccine be strongly recommended by healthcare providers for all individuals 6 months of age and older, and there is adequate coverage and reimbursement by insurance providers,” said Pedro Piedra, MD, professor, department of molecular virology & microbiology at Baylor College of Medicine, Houston.

“Prevention through vaccination is key to being prepared for the unpredictable nature of the influenza season,” Dr Piedra told Formulary. 

The 2013-2014 influenza season is the first time that quadrivalent influenza vaccines will be available in the United States. Previously, only trivalent influenza vaccines were available, which contained 2 influenza A strains and one influenza B strain. Since 2001, influenza B strains from 2 different lineages (B/Yamagata and B/Victoria) have co-circulated each influenza season in the United States. Trivalent vaccine formulations rely on predictions of which influenza B strains will be dominant in the upcoming season. However, B strain circulation has been difficult to predict correctly, and in 6 of the last 12 flu seasons, the vaccine B strain did not match the dominant circulating B strain.

MedImmune, the global biologics arm of AstraZeneca, began shipping Influenza Vaccine Live, Intranasal (FluMist Quadrivalent) to influenza distributors across the United States for the 2013-2014 influenza season. FluMist Quadrivalent is the first and only nasal-spray quadrivalent flu vaccine approved by FDA to help protect against 4 influenza strains contained in the vaccine: 2 influenza A strains and 2 influenza B lineages. 

 FluMist Quadrivalent replaces MedImmune’s trivalent influenza vaccine, Influenza Vaccine Live, Intranasal (FluMist).  A needle-free option for eligible individuals (2-49 years of age) and entire families, FluMist Quadrivalent was developed from the foundation of FluMist. FluMist Quadrivalent is administered as a mist sprayed into the nose, the site at which the influenza virus usually enters the body. The most common side effects of FluMist Quadrivalent are runny or stuffy nose, sore throat, and fever over 100 degrees F.

 The Centers for Disease Control and Prevention (CDC) recommends that everyone aged 6 months and older be vaccinated against influenza as soon as the vaccine is available. The CDC encourages people to obtain vaccinations each year, regardless of whether or not the viruses in the vaccine have changed since the previous season, because immunity can wane over time. 

 First doses of FluMist Quadrivalent shipped the week of July 22. The product is available through private healthcare practices, public health departments, select retail pharmacies including Target and Walgreens, hospitals, school-located vaccination programs, military bases, and other sites.

 FluMist Quadrivalent is covered by more than 99% of health insurance plans with immunization benefits; therefore, most patients who have health insurance for immunizations have coverage for FluMist Quadrivalent. Patients should consult their health insurance plan for more information. ■