'Act quickly, act decisively, act robustly' to stop coronavirus outbreaks, WHO special envoy says

• Countries need to act fast and stop the coronavirus outbreak inside their borders before it grows into an exponential problem, David Nabarro, a special envoy on COVID-19 to the World Health Organization, told CNBC. 
• The quicker they act to limit the virus' spread, the less costly it would be for their respective economies, he said. 
• The global pandemic has infected more than 784,700 people worldwide and at least 37,638 have died, according to data compiled by Johns Hopkins University.

Countries need to act fast and stop the coronavirus outbreak inside their borders before it grows into an exponential problem, a special envoy to the World Health Organization told CNBC. 

Global cases of infection have exceeded 784,700 and at least 37,638 people have died, according to data compiled by Johns Hopkins University.

The outbreak was first reported in China's Hubei province late last year. But in March, the infection spread rapidly across the globe and countries like the United States, Italy and Spain saw exponential growth in the number of people affected by the virus and the disease it causes, COVID-19. 

"This set of outbreaks that are making up the pandemic increase in scale exponentially. They double in size every few days, like every three days," David Nabarro, a special envoy on COVID-19 to the WHO, told CNBC's "Squawk Box Asia" on Tuesday. "Trying to get in ahead of an exponential problem is much easier if you're dealing with it early on." 

Countries are being forced to make difficult decisions as they try to contain the virus within their borders. They need to slow down the rate of infection to a level where their health-care systems can handle the strain and treat everyone. To do that, they are implementing strict lockdown measures that disrupt daily life and adversely impact economic activity, affecting businesses and workers alike. 

For example, Italy has been in a national lockdown since early March. People are only allowed to go to pharmacies and small grocery stores, but the country still has the second-largest number of cases and the highest death toll worldwide. 

India last week told most of its 1.3 billion people to stay indoors, which had an immediate impact on daily wage earners, low-income households and small businesses. Cases in India are relatively low so far, likely due to fewer tests being conducted.

But, places like Singapore have so far managed to avoid a total lockdown because of early decisive actions from the government that included rigorous contact tracing and isolation of suspected patients.

"The real point I have to keep on making is when you get an outbreak starting, suppress it quickly. It's much less costly, it's much less problem for your economy, you don't have to do a long lockdown," Nabarro said.

After implementing a lockdown, countries have to ensure necessary steps are in place such that as soon as the restrictions are lifted, they can quickly identify and isolate infected patients to prevent further transmission, he explained. 

"Act quickly, act decisively, act robustly, so that you're not caught having to deal with a much bigger, bigger problem two weeks later," Nabarro said, adding that it would help to limit the "bitter economic medicine that has to be taken."

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