Vaccinated Flu Patients Might Shed Infectious Fine Particle Viral RNA More Than Others, New Data Suggests

In one study, people infected with influenza A who'd been vaccinated against the flu two years in a row shed more virus in the fine particle aerosol than other people with influenza A or B.

Ted S. Warren / AP Images

In one study, people infected with influenza A who'd been vaccinated against the flu two years in a row shed more virus in the fine particle aerosol than other people with influenza A or B.

Multiple media reports warned us that simply breathing the air around someone sick with the flu might cause us to become infected thanks to fine particle viral RNA. Researchers at the University of Maryland School of Public Health reported in the Proceedings of the National Academies of Sciences that fine aerosol particles collected from the air around patients infected with influenza contained detectable flu virus. Merely exhaling releases the virus into the air if someone is infected. This fascinating new research triggered social media alarm about the flu virus, but there might be even more to the story.

Masks May Provide Little Protection

Earlier this week, an Inquisitr author reported on the story that the flu virus can stay suspended in the air for hours. Though that author and multiple other news sources this week reported that “experts recommend wearing a mask especially in closed areas like an airplane,” it’s not actually as easy as strapping on a surgical mask to avoid becoming infected. The researchers, led by Prof. Donald K. Milton, showed that viral RNA is suspended in air in fine aerosol particles. Surgical masks can protect people from large particles, but don’t perform well against these fine particle aerosols.

“There’s not much evidence that any of that works very well,” Professor Milton told a Time Magazine reporter. “Surgical masks block mostly the large droplet spray, but the surgical masks don’t block the fine particle aerosols very well. The route of infection matters.”

Earlier research conducted by the university showed that surgical masks only reduced fine particle aerosols by 2.8 fold. Yet, in the large particles, the viral copy numbers were reduced by 25 fold by wearing a surgical mask. The large particle viral RNA is not the so-called airborne kind. They are not the particles in the media spotlight about this newly published research.

Fine particle viral RNA may spread the flu through the air by just exhaling.
  Pavel Golovkin / AP Images

Smithsonian Magazine reported that they are currently trying to figure out if these infectious fine particle aerosols actually transmit the flu.

Association Noted Between Repeated Flu Vaccination And Increased Aerosol Generation

There’s even more to this story though, and it could have the potential to complicate things. In the summary published in PNAS, the team noted “an association between repeated vaccination and increased viral aerosol generation” that still needs to be replicated before drawing definite conclusions. Still, it’s not something most people would expect to read at all.

Indeed, these early results showed that the people that had been vaccinated against the flu two years in a row (but still became infected with influenza A) shed more virus in the fine particle aerosol than other people with influenza A or B. They didn’t shed more into the swab of the nose, but the airborne virus data gathered from these repeat-vaccinated people is surprising. The number of participants was clearly very small. The information needs to be confirmed and studied in depth before making any conclusions.

Could further research lead to new recommendations on how to prevent transmission in hospitals, classrooms, subway cars, and other enclosed spaces? According to Science Daily, improvements could at least be made to ventilation systems inside offices, schools, and public transportation at the least to reduce the number of flu cases.

New Game Plan?

It’s still too early to make a new game plan, experts say. Still, we can keep an eye on emerging research out of the University of Maryland and elsewhere. For example, some experts suggest that flu vaccines made using mammalian cells might offer more protection than vaccines made using eggs. Research hints that the egg-adapted H3N2 vaccine strain may result in mutations causing a less effective vaccine in humans. Meanwhile, earlier research into elderberry extract demonstrated that this natural remedy may relieve people of their symptoms by an average of four days when compared to a placebo. The CDC suggests that most people with the flu can seek prompt treatment with Tamiflu or another antiviral drug.

The new research from the University of Maryland certainly makes one thing clear: if you’re starting to show symptoms of the flu, stay home! You’re most infectious at the start of the illness, and no one wants your fine particle aerosols!