As coronavirus spreads around the globe, health experts and aid groups fear some of the world's most vulnerable countries could become new hotspots for COVID-19.

Key points: Health systems are already stretched thin in the Pacific

Health systems are already stretched thin in the Pacific Conflict zones in the Middle East and Africa could compound the health crisis

Conflict zones in the Middle East and Africa could compound the health crisis Dense living makes physical distancing impossible in parts of Asia

Most are concerned about over-crowded refugee camps and countries that are already facing a crisis — whether that be conflict, malnutrition, another epidemic or over-burdened healthcare systems.

Analysis from aid organisation CARE listed 15 "very high risk countries", most of them in the Middle East and Africa — Syria, Iraq, Yemen, Afghanistan, Somalia, Sudan, South Sudan, the Democratic Republic of Congo, Ethiopia, Nigeria, Uganda, the Central African Republic, Chad, Niger and Haiti.

It found they had three times higher exposure to epidemics and six times higher risk in terms of accessing healthcare.

Most high risk countries are in the Middle East and Africa, according to CARE. ( AP )

"This data shows a stark and chilling picture of what we can expect as we start to see the COVID-19 pandemic spread to many Africa and Middle Eastern countries," said Sally Austin, CARE International's head of emergency operations.

An outbreak of coronavirus in parts of the Pacific and Asia could also prove devastating, humanitarian workers warn.

What regions might be at risk, and what are the conditions that could hasten the spread of disease or deepen its impact?

Health systems can't handle an epidemic: The Pacific

The health systems in most Pacific countries were already struggling without a pandemic. ( WHO Western Pacific )

Across the Pacific, countries have been locking down or declaring national emergencies in response to COVID-19 — some even before recording a case of coronavirus.

The health systems in several Pacific countries are already under strain and struggling without a pandemic.

In the face of their vulnerabilities, most countries in the region are implementing strong, pre-emptive measures to try to ensure the virus is stopped before it can get a foothold.

More than 100 cases have now been confirmed in six countries: Guam, French Polynesia, Fiji, New Caledonia, Northern Marianas and Papua New Guinea.

Some countries have also battled other recent outbreaks; the measles epidemic in Samoa killed more than 80 people, mostly children, in recent months; while two years ago PNG saw a resurgence of polio, almost two decades after it had been eradicated.

In Papua New Guinea, the Police Minister has said the country's health system is not capable of dealing with an epidemic and measures are being put in place to stop people "clogging" up hospitals.

A state of emergency was announced in PNG following a confirmed case of coronavirus. ( ABC News: Catherine Graue )

After one case was confirmed in PNG, a 14-day state of emergency was declared that closed the international borders and significantly restricted domestic travel.

The patient was a FIFO mine worker who has since been returned to Australia and so far, no other cases have been recorded, but the lockdown remains in place.

Prime Minister James Marape apologised for the inconvenience but said it was necessary.

"In the limitations of resources, the limitations of infrastructure and the limitations of our health care system, we are absolutely ready to deal with any crisis, if it does emerge," he said.

Around $22 million of Australia's aid to PNG will be redistributed to be used to help prepare for COVID-19.

Fiji has five cases and in response has locked down Lautoka — the country's second-largest city.

The Solomon Islands, Vanuatu, Kiribati and Tonga have all introduced measures to declare national emergencies, lock down borders or restrict activities, despite having not yet recorded any cases of COVID-19.

PNG's Police Minister said measures are in place to stop people "clogging" up hospitals. ( ABC News: Bethanie Harriman )

Katherine Gilbert, from the University of Melbourne's Nossal Institute for Global Health, said there had been strong leadership in the Pacific health sectors, but that many were spread thinly in remote locations and she was concerned about access to personal protective equipment.

"People in Solomon Islands and PNG still rely on traditional medicine or custom medicine as their first port of call to seek care, so you have the possibility of those that do have symptoms delaying presenting to the formal health system," she said.

She worried about the impact of isolation on gender-based violence in the Pacific — a consequence of lockdowns that had reverberated in other countries, including Australia.

"It's definitely something we should be talking about — and there are some great local service providers in the Pacific, but like the health systems, they will be stretched during this time," she said.

Australia's Prime Minister Scott Morrison has warned world leaders at an emergency G20 meeting that Pacific Island nations will need help to respond to COVID-19 and must be a focus of international support.

He said Australia has provided some supplies and expertise and is reconfiguring its aid in the region to ensure critical health services can continue to function.

Only 13 intensive care beds: Spotlight on Guam

The rate coronavirus has been spreading in Guam has alarmed local officials. ( ABC News: Greg Nelson )

The tiny US territory of Guam has recorded almost half of all COVID-19 infections in the Pacific Islands region, and the White House has declared it a major disaster site.

Guam is an island with a land mass of only 549 square kilometres and a population of just 164,000 people.

The rate coronavirus is spreading in Guam is alarming local officials, who have warned the health system could reach "break point" as early as this week.

"For those of you who've played Tetris, and you're getting to the point where you're about to lose and you're scrambling to make room for the bricks as they keep coming through — we've been at that point even before COVID-19," Chief Medical Officer Dr Felix Cabrera said.

"Now, the bricks are coming much quicker."

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Guam recorded its first COVID-19 case in mid-March and it has grown steadily since, with 56 cases now recorded and one death.

Guam only has 250 staffed hospital beds, which includes 13 staffed intensive care beds.

"At our current spread rate, Guam's critical care break point could occur by this week," Dr Cabrera said.

If that happens, Dr Cabrera said the number of deaths could "skyrocket", but he said there is still time to try to turn things around.

"By aggressively slowing the spread rate, we might prevent a break."

Guam's Governor Lou Leon Guerrero said there is still a "small window of opportunity" for Guam to "counter the worse impacts" and said from Tuesday all arrivals will be quarantined for fourteen days in a government facility.

It's not just local transmissions Guam has to contend with, a United States navy aircraft carrier has been diverted to the island after reporting an outbreak of coronavirus while at sea.

At least 36 sailors have coronavirus and all 5,000 people on board are being tested.

The disaster declaration will make more funding available and Guam's Governor has previously requested testing kits and a deployment of the national guard.

Extreme poverty and overcrowding: Africa

Many countries in Africa were already struggling with epidemics and an ongoing food crisis. ( Reuters: Feisal Omar )

In Africa, many countries already struggle with epidemics like HIV, making people immunocompromised, as well as malaria, measles and Ebola. The Horn of Africa is also facing an ongoing food crisis.

"Although there aren't the volume of cases yet in some of these countries, we know that they're very weak in terms of having the ability to understand the epidemic to test and to follow up patients," said Dr Clair Mills from Doctors Without Borders.

Dr Mills pointed out the population is generally much younger in Africa than Europe, with about 50 per cent under the age of 20.

"In many countries, however, there's also extreme poverty and often overcrowding, particularly in urban areas," she said.

"So obviously that's a very good environment for coronavirus to spread very fast."

'In a pandemic, everything changes': Spotlight on DRC

The DRC is still grappling with the world's second largest Ebola outbreak. ( Samuel Sieber/Médecins Sans Frontières )

The Democratic Republic of the Congo is already reeling from a measles outbreak that last year claimed the lives of 6,000 people.

The DRC is still grappling with the world's second largest Ebola outbreak, killing more than 2,200 and infecting 3,400 since the outbreak was declared in August 2018, although Dr Mills said the peak of that epidemic had passed.

"The whole health system there is extremely fatigued from a year and a half of an Ebola outbreak," she said.

"Children who have just had measles do often have immune systems which are suppressed a little, and are really vulnerable to malnutrition and other infections."

She said malaria season was going to start soon for many countries in Africa, and it was too early to tell what toll coronavirus would have on the continent.

"We cannot be clear about the impact in Africa yet. We know that there'll be a lot of mortality related to the fact that if health systems collapse, people won't be able to seek treatment for other things which are also deadly, like malaria, like TB, like HIV, and other infectious diseases which are still common," she said.

"In a pandemic, everything changes and everything's uncertain."

'We fear another Wuhan': The Middle East

NGO's such as CARE have struggled to access certain humanitarian hotpots in the Middle East. ( AP: Oded Balilty )

Sally Austin from CARE said her group had for months faced serious issues accessing humanitarian hotspots in Yemen, Syria and Iraq.

"If COVID-19 spreads in those hard-to-reach places, the consequences could be devastating. People here are already weakened by months and years of violence, lack of health services and malnourishment," she said.

In Afghanistan, thousands of displaced Afghans are flowing over the border from Iran — one of the worst-hit countries in the coronavirus pandemic.

"We fear that Herat will turn into another Wuhan," Afghanistan's minister of public health, Ferozuddin Feroz, said last week, according to the New York Times.



'An outbreak will cause mayhem': Spotlight on Syria

There are many vulnerable people living in makeshift shelters in Syria.

Last week, the war-torn country recorded its first cases of COVID-19. The country has been ravaged by conflict and is under the strain of a fresh offensive in Idlib, leading to mass displacement.

In a statement, CARE said they were concerned about the inability to test for the virus and that many more cases could go undiagnosed.

"Nine years of conflict have left Syria in a shambles," said Nirvana Shawky, CARE's Regional Director for the Middle East and North Africa.

"Not only are many vulnerable people living in tents and makeshift shelters, but civilian infrastructure, including hospitals and health care centres, have been decimated."

She said medical items were scarce and hand sanitiser difficult to find.

The organisation also feared there was limited testing capacity — there were around 900 testing kits made available last week in Idlib, but only one lab, meaning around 20 tests could be processed per day.

It was highly likely, they said, that the virus has been spreading unchecked.

"An outbreak will cause mayhem in an area that has already gone through so much suffering," CARE said.

Cases spreading undetected: Asia

Observers have questioned some Asian nations' ability to detect the coronavirus. ( Reuters: Danish Ismail )

With many people in parts of Asia living hand to mouth, working in jobs that are impossible to do from home, and living in close quarters with family members, the ability to self-isolate and physically distance themselves to stop the spread is limited.

Observers have also questioned some nations' ability to detect the virus. For example, Indonesia was slow to report cases, and until last week had a low rate of testing.

With its population of 270 million, Indonesia has more than 1,200 cases.

But modelling suggests the true number of infections in Indonesia is in the tens of thousands and, depending on the rate of transmission, could be as many as 250,000.

But the low rate of testing isn't confined to Indonesia — there are concerns potential infections could be going unrecorded in countries like Laos and Myanmar too, and that migrant workers travelling to their home provinces in Thailand and Cambodia could be unwittingly carriers of the virus.

'Not passive victims': Spotlight on Bangladesh

Bangladesh hosts more than 850,000 Rohingya refugees in Cox Bazaar. ( Reuters: Mohammad Ponir Hossain )

Over the weekend, a leaked United Nations memo forecasted that without intervention, between 500,000 and 2 million lives could be lost in Bangladesh during the COVID-19 epidemic wave.

Bangladesh currently has 48 cases and five deaths.

Katherine Fell, senior program manager at Plan International Australia with expertise in Bangladesh, said people living in the densely-populated country of 170 million were already badly affected by climate change and where whole families were tightly packed into the slums of Dhaka.

"There are large slum areas where there is no opportunity to socially isolate — it's just not feasible in a place as populous as Bangladesh," she said.

There are tens of thousands of Bangladeshi migrant workers in Italy, and Ms Fell said locals were concerned many may have flocked home, bringing the infection with them.

Bangladesh's Ministry of Manpower did not respond to the ABC's questions about potential recently returned migrant workers from Europe.

Bangladesh also hosts more than 850,000 Rohingya refugees from neighbouring Myanmar in Cox's Bazar. One case has been recorded there, but not in the refugee camp.

"In that part of the world, especially in Cox's Bazar, you're going to be dealing with high levels of density and malaria, and levels of malnutrition, especially in those refugee populations," Ms Fell said.

Another major challenge for Cox's Bazar was the lack of connectivity, with the internet shut down since September last year. Human Rights Watch and others have said communication is essential to spread awareness of the virus and save lives.

To address this, Plan International Australia said it was distributing communications in Cox's Bazar to educate refugees about the virus and dispel myths, as well as increasing access to water, soap, menstrual health kits and providing mental health support.

Despite the challenges, Ms Fell said Bangladeshis knew how to deal with hardship — a case in point being Bangladesh scientists developing a coronavirus test kit.

"They're definitely not passive victims of this. This is a dynamic country full of dynamic people trying to get by," she said.

Additional reporting by Michael Walsh.