One of  Bilthoven Biologicals’ (BBio) employees became infected with the polio virus during his work. Until the cause is completely clear and all processes have been checked again, BBio will cease activities with active polio virus.

Protection of people and the environment

The investigation into the sewage contamination at the Utrecht Science Park in Bilthoven has shown that an employee of Bilthoven Bioloigicals became infected with poliovirus during his work. Because the employee is vaccinated, he has not become ill and is in good health, although he is going through an infection making it a threat to the unvaccinated. That is why, immediately after this discovery, it went into isolation. The isolation is only lifted after the person no longer excretes the virus.

Jan-Eric Zandbergen, CEO BBio: “I am very sorry that one of our colleagues is experiencing a polio infection and is now in isolation. As long as it is not clear how exactly this could have happened, we will not start any activities with poliovirus. We have to find out the exact cause of the infection and look closely at our methods. We have a responsibility to ourselves, but also to our environment. They must be able to rely on us to control our processes and working methods.”

Do everything right

Zandbergen: “Fortunately, at BBio we know how to do this and we will reassess and improve all activities with active poliovirus. All departments will immediately map out the consequences of this and decide which actions will be initiated. Only when we are completely sure that we are doing everything right in our processes, we will again do what we do best: making vaccines to protect people against polio.”

Since 2017, BBio has had some spills due to technical and procedural errors. In the event that a spill occurs or someone becomes infected, the authorities will act. That collaboration is important for our Public Health. In the Netherlands, a well-functioning system is in place, with legislation regulating every step in the process of our polio production. BBio is committed to this. Safety and quality are paramount. Only if we can guarantee this we can ensure that people are vaccinated against polio and prevent them from having to live with the consequences of this disease.


At the moment, deliveries to our customers are not at risk. There is still enough stock to meet the current demand. It is in everyone’s interest that we can produce again under all the right conditions.

Global Polio Eradication Initiative

Since the late 1980s, the WHO has been working successfully to eradicate the disease poliomyelitis in order to make vaccination obsolete. However, vaccination will still be necessary for decades, while the disease will no longer exist, less and less vaccination will be done. The organizations designated by the WHO must then ensure that no more poliovirus is released during the production and testing of vaccines in order not to start new outbreaks where the disease is reintroduced because there is then less protection due to reduced vaccination. The WHO already drew up guidelines for this in 2015, on the basis of which BBio has built a new factory. Next year, a laboratory that complies with these Global Action Plan (GAP) rules will also be delivered. Although the production and testing of polio vaccines will always remain human work, Bilthoven Biologicals remains committed to the WHO goal of eradicating polio as a disease worldwide.