Why is it so hard to combat flu epidemics?

09 Feb 2018 | Back to News, Publications and Annual Reports

Our country is currently in the grip of a major flu epidemic. Such epidemics occur every year. Like clockwork, a new flu epidemic will hit us every winter. It is hard to imagine a year passing without a flu outbreak. But why is it so hard to combat flu epidemics?

Flu is one of BPRC's fields of research. Across the world, many people die each year of flu, caused by the influenza virus. Generally, the victims are elderly people, young children and people with compromised immune systems. Flu shots do not always prevent people from getting the flu. For this reason, we really need better vaccines and medications to protect humans from a wider range of flu viruses.

Flu viruses are unpredictable

Flu viruses are hard to combat because they change all the time. It is even hard to predict which type of virus will hit in a particular winter. Moreover, new subtypes may develop all the time, to which our immune systems are not yet resistant. These new subtypes can result in epidemics or even pandemics (global outbreaks), which will involve many people falling ill and a high mortality rate.

Victoria or Yamagata?

This being the case, it is hard to predict which type of virus will hit a community. Nevertheless, the composition of flu shots administered at any given moment must be based on virus types that were prevalent nine (!) months earlier. This is because it takes nine months to produce a flu shot. This year, too, predictions turned out to be wrong. We are currently being hit by an Influenza B virus. There are two types of Type-B viruses, called Victoria and Yamagata. The current Influenza B virus is a Yamagata-type virus, but the flu shots that have been administered in the Netherlands lately contain a Victoria-type virus. There is nothing we can do about that now.

What we are doing to combat the flu

A significant part of our research focuses on the mechanisms of action of Influenza virus vaccines. BPRC seeks to develop a flu shot that targets many types of viruses at once, since this will make us less dependent on predictions, which we know are not always right. BPRC's vaccine is not produced in fertilised hen's eggs (as usual*), but rather using biotechnological methods (baculoviruses, insect cells). This method has allowed us to reduce production time from nine to three months, which means we will eventually be protected from several types of flu.

* Each dose of the vaccine requires a fertilised hen's egg, which means a lot of eggs are needed. This is one of the bottlenecks in the production of the vaccine.