Cell-Cultured Flu Vaccines Win Again

Cell-cultured flu vaccines were 10 percent more effective in preventing influenza-related hospital encounters and emergency room visits
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A new study of seniors who received an influenza vaccine during the 2017/18 season reported that cell-cultured flu vaccines performed better than egg-based flu vaccines. 

This analysis of 13 million Medicare beneficiaries aged 65+ used Poisson regression to discover cell-cultured flu vaccines were 10 percent more effective than standard-dose egg-based quadrivalent vaccines in preventing influenza-related hospital encounters and emergency room visits. 

This new study’s finding is similar to a previous flu vaccine effectiveness analysis published on November 21st, 2018.   

The November study reported people who were vaccinated during the 2017/18 influenza season with the cell-based, quadrivalent influenza vaccine (QIVc)] were 36.2 percent less likely to display influenza-like illness. 

Those researchers said ‘when produced completely outside of the egg-based flu vaccine process, cell-based influenza vaccines avoid egg-adapted changes.’ 

This means cell-based vaccines may offer a closer match and potentially improved protection compared to egg-based options during ‘some’ flu season. 

Additionally, previous research showed that some H3N2 viruses undergo changes when they are grown in eggs and that these changes may reduce the effectiveness of standard egg-based influenza vaccines in H3N2-dominated seasons. 

In an accompanying editorial to today’s new study, epidemiologists from the Centers for Disease Control and Prevention's (CDC) Influenza Division wrote ‘that the relative effectiveness difference between the cell-culture and high-dose vaccine wasn't statistically significant.’ 

Moreover, these CDC researchers ‘believe that the increased effectiveness of the cell-culture vaccine was likely due to the H3N2 cell-derived component.’ 

"The lessons learned from these studies will help improve influenza vaccines and vaccination strategies, which will optimize the protection provided by seasonal influenza vaccines," they wrote. 

The CDC says the influenza virus is a common, highly contagious infectious disease that can cause severe illness and life-threatening complications in many people. 

To reduce the risk of serious outcomes, the CDC encourages annual flu vaccinations for all individuals aged 6 months and older. 

This CDC recommendation includes pregnant women. 

Two recent studies reported positive safety outcomes when pregnant women received the Inactivated influenza vaccine (IIV).   

On November 23, 2018, a prospective cohort study of 8,827 Australians “FluMum”, published in Clinical Infectious Disease, found that regardless of the trimester, women who received an IIV influenza vaccine did not report adverse birth outcomes, when compared with unvaccinated mothers. 

This comprehensive flu guide from Alarms.org covers everything from flu basics to up-to-date statistics and resources.

If you have flu vaccine questions, it's best to speak with your doctor, nurse or pharmacist, says the CDC. 

There are various flu vaccines available for the 2018-19 season.

The CDC Vaccine Price List provides private sector prices for general information. 

Flu vaccine discounts can be found here.

Vaccines, like any medicine, can have side effects. You are encouraged to report negative side effects of vaccines to the FDA or CDC.