Corona pandemic: Tracing the virus with Nextstrain

Richard Neher is a biophysicist and has been conducting research on epidemiological questions at the Biozentrum of the University of Basel since 2017. Yet never before has his opinion been so highly in demand as right now. Among scientists in Switzerland, he is one of the leading experts on the current pandemic. Managing the day-to-day flood of inquiries is a huge challenge. Diverse media and the authorities rely on him as a well-versed expert during these days dominated by the coronavirus. 

Richard Neher’s colleague Emma Hodcroft, who as a postdoc carries out research with him, is also in high demand as a point of reference since the outbreak of the coronavirus crisis. From day to day more people follow her on Twitter. “Before the coronavirus outbreak, I had a few hundred followers,” says Emma Hodcroft. “Meanwhile the number has grown to over 12,000. It’s incredible.” She is one of the few women who has joined the panel of epidemiological experts.

Open Science

Richard Neher is an advocate of Open Science. His work on the spread of viruses, now that the coronavirus has the world in its grip, highlights the importance of making research results publicly accessible. He and his team depend on this: it is the only way that they can track the spread of the virus.

That Richard Neher is so highly sought-after today is also the result of an innovative idea that he and his colleague Trevor Bedford from the Fred Hutchinson Cancer Research Center in Seattle had some years ago. They wanted to be able to follow in real-time how a pathogen spreads and, to this end, developed the web application Nextstrain. The website has been online since 2015 and has already been used to address diverse epidemiological questions. However, a breakthrough only has come with the coronavirus crisis. In recent weeks the platform has been literally overrun, the website has been accessed over 400,000 times. 

Nextstrain: Tracing viruses

Using Nextstrain, it is possible to trace in real time how the virus changes, that is, which mutations appear as it spreads. The smallest genetic changes provide information about the origin of the virus and the path it takes. As viruses are constantly mutating, due to the error-prone replication of their genetic material, they leave a trace that is easy to follow. 

These mutations are the basis for tracing the spread of the virus. “We could clearly demonstrate this for Italy,” says Richard Neher. “In Italy, the coronavirus was introduced at least via two different routes.” Knowing the routes of infection helps to control epidemics and enables health authorities to take measures to curb the spread of a virus in time, as is currently done by declaring a state of emergency in the case of the coronavirus pandemic.

“The measures taken in Switzerland are also based on the Nextstrain analyses,” says Richard Neher. “When I look at how the virus has spread, the measures to contain the pandemic are fully justified. We must act now to slow down the virus spreading and to prevent our health system from becoming overburdened. Those who are weakened or have an underlying health condition would otherwise pay the price. It is a balancing act between the social and economic consequences.”