Researchers identify “airborne” H5N1 birdflu virus properties

New knowledge may help to prevent pandemics

Researchers at Erasmus MC Rotterdam have discovered which changes can make an H5N1 virus airborne transmissible. In the leading scientific journal Cell, they report today which combinations of mutations are responsible for virus transmission via the airways of mammals. They also identified the biological properties of the mutated virus. This is the first research into the genetic changes and the associated biological properties of the airborne transmissible H5N1 birdflu virus.

In previous work, the researchers discovered that the H5N1 birdflu virus required only few mutations to become airborne transmissible. Now, they identified which combinations of mutations are essential for virus transmission. Two mutations were found to improve the attachment of the virus to cells in the upper respiratory tract of mammals. A third mutation increased the stability of the virus, which is relevant for penetration of the cells. The two remaining mutations were responsible for subsequent efficient virus multiplication.

Some of these mutations can arise spontaneously when mammals become infected, and have already been found to occur in nature. ‘This means that the virus might evolve in nature to become transmissible via couching, sneezing, talking, or breathing. As a consequence, the H5N1 virus still represents a pandemic threat’, says virologist Ron Fouchier.

By increasing fundamental knowledge of virus transmission, it will be possible to improve surveillance programs and to identify potential pandemic threats as early as possible. In addition, the researchers will be able to better evaluate existing and new vaccines and drugs against a birdflu virus that is airborne transmissible between mammals.

The research was primarily funded through the EU FP7 programs ANTIGONE and EMPERIE and a contract with NIAID/NIH.  A link to the manuscript in Cell is here