Bloomfield said the definition of "coronavirus elimination" was getting down to a small number of cases that can be stamped out with rapid identification, isolation and contact-tracing.
Governments around the world are grappling with how to begin easing the coronavirus lockdowns imposed to stem the spread of the disease which has killed more than 83,000 people worldwide.
There are fears that continued strict social distancing not only risks a backlash from those forced to live with tight restrictions, but will also do lasting damage to national economies.
But while some countries have announced ways their lockdowns may be relaxed in the weeks to come, governments and health authorities around the world warn it must be done in a way that avoids a sudden resurgence in the spread of Covid-19.
In China - where the coronavirus first emerged - the authorities have begun gradually easing restrictions.
People were being allowed to leave the city of Wuhan, the first epicentre of the pandemic, for the first time from Wednesday, as long as they are in possession of a "green code" on an official smartphone app.
As infection rates dropped last month the authorities began easing the city's lockdown, allowing people out of their homes for two hours a day.
In other regions and cities, where the outbreak was less severe, the majority of shops, restaurants and workplaces have begun to reopen, although there are fears of a second wave of cases as people return to work.
From April, Chinese citizens returning from overseas will be required to declare their health status and travel history through a social media app prior to boarding.
Taiwan and Singapore have been praised for their containment of the coronavirus, but infections have spiked in recent weeks as citizens abroad return from the US and Europe.
Both governments have stepped up measures to limit travel and enforce social distancing, with
Singapore this week banning social gatherings, both indoors and in public.
This follows the decision last week to close schools and most workplaces for a month.
Taiwan stands out as one of the few countries that has not gone even under a partial lockdown, relying instead on early detection of imported cases.
But the throngs of people at domestic tourist destinations over the recent long weekend scared the authorities into issuing tougher rules, including a NT$15,000 ($820) fine for people who refuse to wear face masks on public transport.
People wear masks at a supermarket in Milan, Italy. Photo / AP
A team of academics at the National Taiwan University has suggested it would be more effective to contain neighbourhoods rather than ordering a blanket lockdown of an entire city.
As the first Western democracy to face the coronavirus pandemic, all eyes are on Italy to see how the country forges an exit strategy.
The national lockdown officially ends on Easter Monday, but is almost certain to be extended.
However, there is speculation that as the number of deaths and infections begins to gradually dip the government might give a few key industries and businesses permission to reopen.
Any such initiative would come with tight conditions, such as workers being required to maintain social distancing and wear facemasks at all times.
Pier Carlo Padoan, a former economy minister, said he feared that if the shutdown continued for too long, Italy risked "economic collapse".
Under an exit strategy to be devised by the Government's scientific committee, offices and shops could reopen but not bars, gyms, restaurants, nightclubs, cinemas or theatres. There is a strong chance that schools will not reopen until September.
There would be widespread testing of people as well as tracing of those who might have been newly infected.
In Brescia, one of the northern cities that was worst hit by Covid-19, it has been suggested that younger people should be allowed to return to work soonest, because they are less vulnerable to the virus. That could help restart the 70 per cent of the city's businesses that were shut down as a result of the emergency.
"People who are under 45 are at less risk, so they could return to work first," said Giuseppe Pasini, the president of Brescia's association of industrialists. "It's time to think about how we can live with the virus until a vaccine arrives."
But experts remain extremely cautious, warning that if the lockdown is relaxed too quickly, infections could flare again and Italy could find itself back at square one.
Spain
Cases: 146,690 Deaths: 14,555
In announcing the extension of Spain's strict lockdown regime through a sixth week until April 26, Prime Minister Pedro Sánchez warned that the restrictions would not end there.
The stubbornly high plateau at which the Covid-19 daily death rate has settled – more than 700 on Tuesday and Wednesday – means that the return to normality will have to be phased in and highly controlled.
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An exceptional 10-day measure to keep all non-essential workers at home lapses on Thursday, meaning that building sites, factories and call centres will start to operate again.
Spanish families suffer the strictest rules in Europe, with not even children allowed out to exercise. But Spaniards seem to have accepted the restrictions. A macro-survey of 146,000 people found that 44 per cent were happy to spend another month indoors, with 21 per cent prepared to last three months if required.
Spain plans to start mass testing to check for herd immunity from next week. Areas where sufficient herd immunity has been achieved will be able to relax social-distancing measures earlier than others.
Germany
Cases: 107,659 Deaths: 2017
The federal government has tried to downplay hopes of existing restrictions being eased soon, with Chancellor Angela Merkel saying it would be "irresponsible" to give a date for the ending of restrictions.
Doctors from France discuss in front of room where a COVID-19 patient from France is being treated at the University Hospital in Essen, Germany. Photo / AP
However the authorities are examining ways of achieving a lifting of lockdown measures through technology.
One such solution could involve the use of an app to monitor who individuals have been in contact with, so as to alert them to the need for testing.
This would rely on people freely reporting if they had tested positive and would need to be voluntary to accommodate the German obsession with privacy and fear of surveillance.
Austria
Cases: 12,738 Deaths: 2732
Austria said earlier this week it was turning a corner and would start reopening more shops after Easter, following a downward trend in the growth rate of new infections.
Chancellor Sebastian Kurz outlined a series of phases to return to normal life while minimising the risk of a surge in new infections.
Smaller non-essential stores and DIY shops will be opened on April 14, followed by all shops, malls and hairdressers on May 1. However, schools are to remain closed for the indefinite future.
Denmark
Cases: 5,386 Deaths: 218
Denmark has seen the number of hospital admissions and deaths stabilise over the past week, following its early closure of schools, restaurants, cafes, gyms and the nation's borders.
It plans to reopen day care centres and schools on April 15 as a first step to gradually easing the three-week lockdown.
Prime Minister Mette Frederiksen said: "If we go too fast it can go wrong. Therefore, we must take one cautious step at a time."
In the US, where the pandemic has reduced New York and other cities to ghost towns, there is unlikely to be any easing of restrictions for several weeks.
President Donald Trump has said federal social distancing guidelines will remain in place until at least the end of April, but he is eager to reopen the economy as soon as possible.
He has floated the idea of staggering the return of the workforce, suggesting "large sections" of the country that are not affected by coronavirus could be asked to get back to work.
However,Trump does not have sole control over the decision. State governors have put stay home orders in most US states which prevent many businesses from reopening, and it will be up to each state when they decide to lift those restrictions.
One decision that rests solely with the President is when he decides to lift travel restrictions.
Trump is being lobbied by US airlines which have been hit badly by the travel restrictions and he has talked repeatedly about protecting companies like Boeing.
But in White House briefings, officials have warned they will not lift travel restrictions to European countries until they have "recovered from the effects of the virus".
Iran
Cases: 67,286 Deaths: 4,003
After initially struggling to cope with the rapid spread of the virus Iran is now seeing the number of new cases fall.
In a bid to repair an economy already struggling with international sanctions President Hassan Rouhani announced that "low risk" business activity will resume from Saturday April 11).
Outside of Tehran, the epicentre of the outbreak, government employees will return to work, but schools, universities and various social, cultural, sports and religious events will remain suspended until at least to April 18.
