The key in the battle against coronavirus is to "test, test, test", according to the World Health Organisation.
Speaking at a press conference on Monday, Dr Tedros Adhanom Ghebreyesus, director general of WHO, said finding out that you are suffering from Covid-19 is the best way to treat it.
Currently, only people who are hospitalised are being tested for coronavirus in the UK, where there has now been 1,543 confirmed cases and a total of 53 virus-related deaths.
"The most effective way to prevent infections and save lives is breaking the chains of transmission, and to do that, you must test and isolate," Dr Tedros said.
"You cannot fight a fire blindfolded and we cannot stop this pandemic if we don’t know who is infected.
"Once again, our key message is: test, test, test.
"This is a serious disease.
"Although the evidence we have suggests that those over 60 are at highest risk, young people, including children, have died."
The number of confirmed cases is constantly increasing across the western world and there are now more cases outside of China - the epicentre of the respiratory disease - than inside it.
"In the past week, we have seen a rapid escalation of cases of Covid-19," the WHO chief said.
"More cases and deaths have now been reported in the rest of the world than in China."
He said there had been "a rapid escalation in social distancing measures, like closing schools and cancelling sporting events and other gatherings.
"But we haven't seen an urgent enough escalation in testing, isolation and contact tracing, which is the backbone of the response."
WHO feel there is a need to lengthen quarantine periods for those who contract coronavirus.
"People infected with Covid-19 can still infect others after they stop feeling sick, so these measures should continue for at least two weeks after symptoms disappear."
Prime Minister Boris Johnson has said "drastic action" now needs to be taken as he outlined new measures to try and combat coronavirus.
In the first of the Government's daily briefings, Mr Johnson said that "now is the time for everyone to stop non-essential contact and to stop all non-essential travel".
England's chief medical officer has defended the Government's position on testing people for Covid-19.
Professor Chris Whitty said there was "complete surveillance" testing in intensive care in the UK, while hospitals were also testing patients with pneumonia and GPs were testing in the community.
"We do intend to continue to scale up testing," he said, adding efforts were already "substantial" with more than 44,000 tests conducted overall.
Coronavirus: Everything you need to know