Zika and yellow fever-vaccines without eggs

A team led by researchers from the Max Planck Institute for Dynamics of Complex Technical Systems in Magdeburg is developing methods with which viruses for vaccines can be replicated in significantly higher concentrations than before. 

The researchers produce the pathogens in cell cultures in small bioreactors. The production of vaccines currently requires about half a billion chicken eggs per annum, which causes some problems.

The production of vaccines often suffers from complications and bottlenecks. Because production must be planned years in advance, changes in vaccination recommendations, quality defects or even economic calculations by the few companies in the vaccine market have far-reaching consequences for the supply of the protective substances.

A team led by Yvonne Genzel and Alexander Nikolay from the Max Planck Institute for Dynamics of Complex Technical Systems is working on preventing such problems from occurring in the future. Researchers are combining several approaches for the production of flaviviruses under ideal conditions, including the pathogen that causes yellow fever.

First they multiply animal cells in a bioreactor filled with nutrient solution, which serve as hosts for the viruses. Researchers have achieved cell concentrations in the bioreactor up to 75 times higher than the usual standard.

The researchers then infect the cells with yellow fever viruses. In doing so, they use another trick to achieve the highest possible virus concentration. The scientists use a pathogen that they have previously adapted to multiply particularly well in animal cells. With the new production method, the number of yellow fever viruses that multiply in a bioreactor with one litre capacity in two weeks is equal to the number required for ten million vaccine doses.