Universal, Live-Attenuated, One-Shot Flu Vaccine Could Be Available Within Five Years

Scientists announced a big break in the search for a universal flu vaccine in the wake of the news that this year’s seasonal flu vaccine was only about 25 percent effective. A universal flu shot would help avoid the predicament Americans have found themselves in this year. Each year, flu vaccinologists attempt to create a flu shot based on the anticipated strain for the season, but sometimes, as was the case this season, they choose the wrong strain. The research about the potential universal, live-attenuated flu vaccine was published in the Journal of Virology.

The universal flu shot that the researchers are working on would be to protect against flu illnesses from influenza A, according to Medical News Today, and will help to prevent pandemic flu situations. While this universal flu shot would be expected to protect against a broad range of influenza A viruses, unfortunately, it would not protect against influenza B, as IFLScience pointed out.

The big break came from researchers at McMaster University and the Icahn School of Medicine at Mount Sinai, and it could mean that instead of yearly shots against the flu, people could be given just one flu shot, one time, and it would work universally, even when the virus mutates. The team isolated antibodies that were universal. They even found the antibodies in their natural setting: human blood.

In the past, universal vaccine type antibodies were far less effective at neutralizing the flu virus, but when they grabbed the antibodies from human blood, the universal vaccine became as effective as the individual strain type of vaccines, according to the findings. The researchers also said that they discovered that a live-attenuated version of a flu vaccine would be more effective than an inactivated universal vaccine.

The press release explained how it would work.

“The inactivated vaccine (or ‘flu shot,’ as it is commonly known) consists of virus particles which are grown in eggs under controlled conditions and are then killed using a detergent-based method. The attenuated vaccine, on the other hand, was created by reducing the virulence of the pathogen, but still keeping it viable or ‘live.’ The attenuation allows the virus to replicate harmlessly in the upper respiratory tract so that an immune response can be generated, but renders it useless at infecting the lung where disease normally occurs.”

Currently, the nasal spray offers a live-attenuated version of the seasonal flu vaccine, but the nasal spray vaccine is not a universal flu vaccine, and it only offers seasonal protection. The current live-attenuated seasonal flu vaccine is preservative free, and there is evidence that this version of the flu vaccine may work better for children than other flu vaccines. Still, given that it includes a weakened, but live, virus, the CDC says that young children with asthma, for example, and pregnant women should not get the live-attenuated version. There is also a small chance that it could spread the weakened virus to others, according to the CDC, but it has not associated with severe illness.

“Data indicate that both children and adults vaccinated with nasal spray flu vaccine can shed vaccine viruses after vaccination, although in lower amounts than typically occurs during shedding of wild-type influenza viruses. Rarely, shed vaccine viruses can be transmitted from vaccine recipients to unvaccinated persons.”

It’s unclear if the researchers will be making it so that the future universal, live-attenuated version of the flu vaccine will be more universally tolerated, but for many, this one-time-only flu vaccine could be just what the doctor ordered, according to the media buzz.

[Photo by AJC1 on Flickr]