Topline
Researchers are pitching a new vaccine method for infants that offers continued protection with just a single dose, even if the virus mutates, according to a new study that could set the stage for “universal vaccines.”
Key Facts
Vaccines for diseases like the flu are updated annually to accommodate for new variants, while vaccines for some diseases like COVID-19 are updated less frequently to target dominant variants of the virus circulating in the U.S.
There are different ways to create vaccines, but one of the most popular ways to make them is by including a weakened or inactive version of the virus, which in turn causes the body’s immune system to produce T-cells that attack the virus and prevent it from spreading.
This new vaccine strategy—tested on mice—also uses a modified version of a virus, but instead of relying on the body’s immune system response, it uses small interfering RNA molecules (siRNA), which stop the spread of disease, to create separate vaccines that target different diseases, according to a study published Monday in the Proceedings of the National Academy of Sciences.
Diseases thrive because they produce a protein that can block the production of siRNAs, but the new vaccine strategy creates and uses a mutant virus that can’t produce these proteins, which allows the body’s siRNAs to weaken the virus, regardless of if it mutates and makes a new variant.
The research team from the University of California, Riverside, believes because this strategy doesn’t rely on the body’s immune response to disease, it will also be suitable for babies, whose immune systems are still developing.
The researchers tested this method in baby mice and discovered they also produce siRNA, so they vaccinated them against a mouse disease called Nodamura, and they found the vaccine induced “rapid and complete protection” against the virus.
Crucial Quote
“It is broadly applicable to any number of viruses, broadly effective against any variant of a virus and safe for a broad spectrum of people,” Rong Hai, a study author and virologist at the University of California, Riverside, said in a statement. “This could be the universal vaccine that we have been looking for.”
Key Background
Though there are some approved vaccines for infants, vaccines for diseases like measles, COVID-19 and the flu can only be administered to people over the age of six months. This is because of their immature immune systems that cause a diminished response to these vaccines, and a potential lack of effectiveness, according to a study published in Vaccine. However, this group of people is one of the most susceptible to severe infection. Infants younger than six months have the highest risk of being hospitalized due to flu infection, according to the Centers for Disease Control and Prevention. In order to protect this population from infection, it’s recommended that all household members and people who come into close contact with them get vaccinated from these diseases. Some research shows vaccinated mothers may pass antibodies to fetuses through the umbilical cord, and newborns via breast milk that can continue to protect the babies from infection. Respiratory syncytial virus (RSV) vaccines given to pregnant mothers have proven to protect infants up to six months after birth, according to the CDC.
Tangent
Though there aren’t any approved siRNA vaccines, researchers are working on ones that target COVID-19 and the flu. It was previously debated whether humans and other mammals use interfering RNA to kill viruses. However, the same team from the University of California, Riverside also conducted research in 2013 that discovered this theory was true. The team later went on to prove flu infection causes the body to produce interfering RNA, so they’re in the process of developing a flu vaccine that uses this strategy.
Surprising Fact
The researchers intend on creating this vaccine as a nasal spray rather than a shot. “Respiratory infections move through the nose, so a spray might be an easier delivery system,” Hai said. There’s already an approved nasal spray flu vaccine that’s shown to be as effective in children as flu shots, according to the CDC. Several research teams are working on nasal COVID-19 vaccines, and both China and India have approved the use of nasal sprays in the form of boosters.
