You are congested, have a fever and a severe headache, and your whole body is in pain. An influenza virus has entered your airways, and now your immune system is responding. You feel quite ill. The simplest way to prevent influenza is to get vaccinated before flu season starts.
However, there’s a problem with the vaccines we have today – the influenza viruses that make us sick are continuously changing, and the vaccines must be adapted to each virus.
– Today’s vaccines are overwhelmingly virus specific. This means the vaccines need to be redeveloped each year in order to be effective against the various viruses we get infected with, says Gunnveig Grødeland, researcher at the University of Oslo.
In addition, vaccines take a long time to develop – each new influenza vaccine takes 7 months on average to develop. This weakens the effectiveness of the vaccine.
– Due to the long production times, we have to guess one year in advance which viruses are going to cause the following year’s influenza epidemic, she says.
Grødeland and her colleagues have now come up with a new way of developing vaccines that can protect us against several flu types simultaneously.
– With this method, we are able to develop influenza vaccines that give protection against more influenza types than the current vaccines, and give us broader defence against the disease. This goes for both the seasonal flu and potentially pandemic influenza types that can affect a great number of people, she explains.
Mixing several different influenza types
When scientists are developing a new vaccine, they include the protein haemagglutinin, which is the main surface protein of the flu viruses. As part of their research, Grødeland and her colleagues have combined haemagglutinin proteins from six different influenza viruses. They tested their new vaccine concept on mice.
– Upon vaccinating the mice we observed substantial immune responses towards all the influenza types covered by the vaccine, says Grødeland.
In addition, the researchers saw that by mixing several viruses in a single vaccine actually gave protection against viruses they did not include in the vaccine.
– The combination of viruses makes those parts that the many different influenza types have in common extra visible to the immune system, she says.
Providing us with broader protection
The findings of Grødeland and her colleagues are important for several reasons.
– If we can include several viruses in the vaccine, it will increase the likelihood of us guessing correctly which viruses are coming next time, she says.
Another consequence is that researchers also can include potentially pandemic influenza types in the regular vaccines against the seasonal flu, and that way establish a broader defence against influenza.
– With a mixed vaccine of this kind, we may be able to establish a broad defence against most, if not all types of influenza that may come our way in the future. This would be of great importance – particularly if we suddenly face an unexpected pandemic outbreak.
New ways of thinking about vaccines
For some, influenza can feel like a really bad cold. However, influenza can also cause serious illness, and can result in serious infectious diseases for some patients. It can also cause pandemics over vast geographical areas. We need to re-think our existing vaccine strategies.
– It might not be possible for us to produce enough vaccines in case of a pandemic outbreak. This is why we have been looking into concepts for providing broader protection, says Grødeland.
Reference
This article is based on the work of research line student Ane Marie Anderson, along with Bjarne Bogen and Gunnveig Grødeland.