Influenza is a viral infection that attacks your respiratory system — your nose, throat, and lungs. Influenza is commonly called the flu, but it’s not the same as stomach “flu” viruses that cause diarrhea and vomiting.
For most people, the flu resolves on its own. But sometimes, influenza and its complications can be deadly. People at higher risk of developing flu complications include:
- Young children under age 5, and especially those under 6 months.
- Adults older than age 65.
- Residents of nursing homes and other long-term care facilities.
- Pregnant women and women up to two weeks after giving birth.
- People with weakened immune systems.
- People who have chronic illnesses, such as asthma, heart disease, kidney disease, liver disease, and diabetes.
Though the annual influenza vaccine isn’t 100% effective, it’s still your best defense against the flu.
Antibodies against the major surface glycoprotein hemagglutinin (HA) are critical for proving protection against influenza virus infection.
New Study Findings
Scientists from the University of Chicago and Icahn School of Medicine at Mount Sinai have identified a new Achilles’ heel of influenza virus, making progress in the quest for a universal vaccine.
Antibodies against a long-ignored section of the virus have the potential to recognize a broad variety of flu strains, even as the virus mutates from year to year. The results were reported in the journal Nature.
The influenza virus affects more than 20 million people in the United States in a year and leads to more than 20,000 deaths. Vaccines against influenza typically coax the immune system to generate antibodies that recognize the head of hemagglutinin (HA), a protein that extends outward from the surface of the flu virus. Unfortunately is one of the most variable proteins of the virus.
In the study, researchers characterized 358 different antibodies present in the blood of people who had either been given a seasonal influenza vaccine, were in a phase I trial for an experimental, universal influenza vaccine, or had been naturally infected.
The antibodies that stood out were the ones bound to the very bottom of the stalk, near where each HA molecule is attached to the membrane of the flu virion. They named this section of HA the anchor.
They identified 50 antibodies to the HA anchor and they recognized a variety of H1 influenza viruses, which account for many seasonal flu strains.
The researchers believe that in the near future, improved iterations of a universal vaccine could more purposefully aim to generate anchor antibodies and are planning future studies on how to design a vaccine that most directly targets this anchor of different influenza strains.
Jenna J. Guthmiller, et al. Broadly neutralizing antibodies target a hemagglutinin anchor epitope. Nature, 2021; DOI: 10.1038/s41586-021-04356-8.
Scripps Research Institute. “No more annual flu shot? New target for universal influenza vaccine.” ScienceDaily. ScienceDaily, 23 December 2021.