Universal Flu Vaccine Protects Against Influenza A, B Virus Variants, Study Results Show

A new universal flu vaccine protects against variants of both influenza A and B viruses in mice, according to the results of a study by the Institute for Biomedical Sciences at Georgia State University.¹

Investigators designed a single, universal influenza vaccine candidate that has cross-protective and less variable parts of both influenza viruses, including multi-neuraminidase protein subtypes known to be major antiviral drug targets as well as the M2 ectodomain protein.¹

“We developed a single, universal vaccine entity that induced immunity to conserved M2 ectodomain and multi-subtype neuraminidase proteins and was found to be effective in conferring broad cross protection against antigenically diverse influenza A and B viruses in young and aged mice,” Sang-Moo Kang, PhD, a professor in the Institute for Biomedical Sciences at Georgia State University, said in a statement.“This study provides impactful insight into developing a universal influenza vaccine inducing broad immunity against both flu A and B variants in young and aged populations.”¹

The study results, published in PLOS Pathogens, showed that mice who were vaccinated with an immune stimulating virus-like particle were protected against influenza A seasonal variants, pandemic potential virus, and influenza B viruses, containing substantial antigenic variations.¹

The viral variants occur when flu pathogens change the surface hemagglutinin protein that binds to host receptor molecules, according to the statement.

Continuous mutational changed in the hemagglutinin proteins cause the emergence of variants that lead to severe flu spread.¹

Current vaccines are based on specific strains for immunity to hemagglutinin, and annual vaccination is recommended. However, the seasonal vaccine effectiveness is unpredictable and could be below 20%, because of continuous changes in these proteins.¹

The study results support a new strategy for creating a universal vaccine against influenza A and B viruses.¹

A single construct displaying multiple cross-protective proteins can also induce immunity to M2 and multi-subtype neuraminidase proteins of influenza A and B viruses.

This can also offer broad-cross protection against sickness and mortality, because of lethal flu virus challenges in mice, the study results show.¹

Vaccinating mice with the universal vaccine elicited broad neuraminidase inhibition, M2 ectodomain specific antibodies, and T cell immune responses. The cross protection was also comparable in aged mice.¹

The results warrant further testing of the unique, universal vaccine candidate in ferrets, which have similar respiratory tracts to humans, investigators said.¹

The National Institute of Allergy and Infectious Diseases of the National Institutes of Health funded the study.¹

The CDC estimates that 9 million to 41 million individuals had the flu, annually between 2010 and 2020. Additionally, there were approximately 140,000 to 710,000 hospitalizations and 12,000 to 52,000 deaths, annually, between 2010 and 2020.²

Although the effects of the flu vary, it burdens the health of individuals in the United States each year, according to the CDC.²

Reference

1. Universal flu vaccine protects against variants of both influenza A and B viruses, biomedical sciences researchers find. News release. EurekAlert. August 25, 2022. Accessed August 26, 2022. https://www.eurekalert.org/news-releases/962763

2. Disease burden of flu. CDC. Updated January 7, 2022. Accessed August 26, 2022. https://www.cdc.gov/flu/about/burden/index.html#:~:text=While%20the%20effects%20of%20flu,annually%20between%202010%20and%202020.