Researchers One Step Closer to Personalized Flu Vaccines

The Centers for Disease Control and Prevention’s (CDC) FluView report for Week 46, ending November 18, 2017, was the first of the 2017-2018 flu season to include states reporting widespread influenza activity.

The health departments from the 2 states with widespread flu activity—Louisiana and Oklahoma—have reported outpatient visits for influenza-like illness rising above the regional baseline, and an increase in influenza-related hospitalizations. Most of the hospitalizations in Oklahoma have involved individuals 50 years of age and older and children under the age of 5. In Louisiana, where an estimated 3,000 flu-related hospitalizations and 500 deaths occur every year, the health department announced that it was instituting a flu vaccination clinic, which opened up to the public yesterday, November 28.

It is well-known that receiving a flu shot is the best way to prevent falling ill with the virus. However, health officials say that individuals who do catch the flu can still do their part to not spread it. “It is important to stay home from holiday gatherings if you have symptoms of influenza which are fever, chills, body aches, and a cough or a sore throat,” said Oklahoma state epidemiologist Kristy Bradley, DVM, MPH, in a recent press release. “It is better to miss out on some holiday fun than risk infecting others. Flu can be especially dangerous for pregnant women, young children, the elderly, and those who have underlying health conditions such as asthma and other lung diseases.”

The onset of flu season has taken a quick and early toll on California’s San Diego County, where officials already have their hands full with the ongoing hepatitis A outbreak. The county’s Health and Human Services Agency reported on November 22, 2017, the fourth flu death there this season. The most recent case involved a 92-year-old man who died after falling ill with influenza A. This time last season the region reported 174 flu cases and 1 death; already, there have been 574 laboratory-confirmed cases of the flu there this season.

However, things might be looking up when it comes to the fight against flu. In a new study recently published in the journal Vaccine, researchers from The Johns Hopkins Bloomberg School of Public Health made a discovery that could lead to the development of personalized versions of the live attenuated influenza vaccine (LAIV), which is made from weakened components of the flu virus.

Last year, the CDC stopped recommending the LAIV for the prevention of the seasonal flu after the vaccine showed a mere 3% effectiveness during the 2015-2016 season. In an interview with Contagion ^®, study author Andrew Pekosz, PhD, said that the H1N1 component of the LAIV, in particular, had failed to provide protection for several seasons.

“This was very unexpected and studies are still being done to determine why this happened, but it most likely is due to poor replication of the H1N1 component of the vaccine,” said Dr. Pekosz. “Not all studies agree on this, as there are some studies from outside the United States that show the LAIV is providing some protection from influenza.”

In their investigation, the study team found that by altering the mutation on the virus’s M2 protein, they could regulate how quickly the virus replicates, and thus, may be able to increase the virulence of the vaccine to cause a stronger immune response. The findings could lead to the development of vaccines that are more effective in specific populations, such as the very young or the elderly, who are at high risk for developing flu-related complications.

“We need to move our experiments into animal models of disease to show how the effectiveness of LAIV vaccines varies with or without the M2 protein mutations,” said Dr. Pekosz. “By making a panel of LAIV with different mutations, we might be able to make better vaccines for the current age groups (2-49 years of age) LAIV is used in, and perhaps make versions of LAIV that could be used in those younger than 2 or older than 65 — which are the two groups that are most affected by influenza disease.”