Train and bus operator Go-Ahead warned today that its profits could be hurt by coronavirus but said so far it had seen minimal impact on demand. 

"At this moment in time it is not affecting us, not in any dramatic way because people haven't changed their travel patterns yet," CEO David Brown said in an interview today. 

But over the coming months, that could change. "If people are told not to travel, that would not be good," he said. 

Go-Ahead operates the GTR rail network in London and south east England, as well as London buses and buses in other parts of the UK. It also operates bus services in Ireland. 

When ask if coronavirus was a risk to this year's profit guidance, Brown said it was, although he said Go-Ahead was helped by the fact that three-quarters of its revenue is based on contracts. 

The company today downgraded its annual profit outlook "slightly" for the year to 27 June due to higher costs in its regional bus business, and from the impact of storms in recent weeks in the UK. 

Adverse weather means people travel less, said Brown, while in its regional bus units, worsening congestion in towns was hurting profitability at the same time as costs rise as it invests in greener vehicles. 

Shares in Go-Ahead plunged 19% in London trade today.