These are the countries where coronavirus cases are rising fastest as WHO warns the pandemic is 'one big wave'

Prime Minister Boris Johnson has expressed concerns that Europe is showing signs of a “second wave” of coronavirus, following a recent spike in cases in Spain.

Mr Johnson defended the government’s decision to impose a 14-day quarantine restriction on travellers who return from Spain, including the Balearics and Canary Islands, and warned the UK must be “vigilant” over the threat of a second wave here.

Is Europe seeing a second wave?

The World Health Organization has said that the current pandemic is in fact unfolding in “one big wave”, rather than surges, and there is no evidence that coronavirus follows the same seasonal variations as is common with flu or the common cold.

Margaret Harris, a spokesperson for the WHO, stressed that continued discussions of a resurgence or seasonal return of the virus is not helpful in understanding how coronavirus is spread.

Speaking at a virtual briefing in Geneva, Ms Harris warned that vigilance in applying and following measures to help slow transmission is of the utmost importance, as coronavirus spread appears to be accelerated by mass gatherings.

Ms Harris said: “People are still thinking about seasons. What we all need to get our heads around is this is a new virus and this one is behaving differently.

“It’s going to be one big wave. It’s going to go up and down a bit. The best thing is to flatten it and turn it into something lapping at your feet.”

However, some health experts argue that the term “second wave” should not be used to describe a surge in infections as the virus has not yet gone away.

As such, what countries such as Spain are seeing is rather a localised spike in the number of cases.

“Dozens of waves”

While the WHO has warned the pandemic is one large and still-accelerating outbreak, it is considering the rate of transmission from a global perspective, with worldwide cases doubling in the past six weeks.

However, when looking at cases regionally, what can appear as a second wave could in fact be the same country experiencing the epidemic in different phases, with one region slightly behind the other.

Keith Neal, emeritus professor in the epidemiology of infectious diseases at the University of Nottingham, told The Guardian: “What we are seeing are spikes in many countries, and in Leicester [in the UK] and other places.

“Some people might call these waves but if they do we are looking at dozens of waves.

“Even in Australia [in Victoria] there is clearly an upturn but the disease was only at low levels to start with, so it’s down to a vague terminology.”