Cuba's President Miguel Diaz-Canel announced over the weekend that the COVID-19 pandemic on the island was "under control" after eight straight days without any deaths.

He cautioned against complacency, noting a recent hike in new infections. But the news shone a spotlight on Cuba's healthcare system.

The country of 11.2 million people has reported 2,205 cases and 83 deaths since COVID-19 hit the island in March, according to a Johns Hopkins tally, resulting in a rate of about seven deaths per million people – far below most European, North American and Latin American countries, according to the World Health Organization (WHO) Coronavirus Disease Dashboard.

Compulsory masks, strict quarantining of people in isolated facilities, and fines or even prison sentences for violating health safety measures contributed to a limited spread of the disease. The island's geography allowed it to isolate itself by suspending air and sea traffic.

But for many, Cuba's free universal healthcare system also deserves much of the credit.

A WHO publication previously described it as "one of the world's most effective and unique" systems. Former UN Secretary-General Ban Ki-moon called it "a model" for other countries around the world. 

Despite its poor infrastructure, lack of funds and a decades-long U.S. embargo, Cuba has the highest percentage of physicians in the world, with 8.4 per 1,000 people, according to the World Bank.

People on the island have a life expectancy of 79 years – above the world average of 73 and just a few years less than wealthy nations like Japan, Switzerland or Singapore – and its child mortality rate is among the lowest in the world. 

Cuba has long focused on family medicine, community work and disease prevention, and a network of hundreds of polyclinics covers the country, alongside neighborhood-based family doctor-and-nurse offices.

This community approach came in handy when the epidemic struck.

Tens of thousands of family doctors, nurses and medical students were sent to knock on doors, going daily from home to home to check if residents had any COVID-19 symptoms, such as a cough or fever.

This helped to detect cases early, as well as communicate safety measures with the population.

Read more: Cuba controls COVID-19, but the risks remain

The method was not new: family doctors in Cuba have long done rounds to look for transmittable diseases. Every autumn, medical staff go door-to-door to check for cases of dengue, said one student.

"We don't have the technology of rich countries, but we have human personnel that is very qualified, with great solidarity and selflessness," a doctor doing neighborhood rounds told AFP news agency.

Cuban doctors are paid little and the healthcare system is plagued with crumbling facilities and medical supply shortages, but the island continues to churn out a large number of well-trained medical students, in part due to its prestigious Latin American School of Medicine (ELAM), and doctors have the people's trust.

While there has been criticism of the harsh quarantine measures for people suspected of having COVID-19 and their contacts – rather than requiring them to stay at home as others countries did – Cuba's centrally planned system meant the government was able to mobilize resources quickly to fight the pandemic, experts from University College London noted in a recent article.

William Leogrande, a specialist on Latin America at American University in Washington DC, agreed that Cuba's healthcare model was almost tailored to tackle COVID-19.

"We know scientifically that quick identification of cases, contact tracing and quarantine are the only way to contain the virus in the absence of a vaccine – and because it begins with prevention, the Cuban health system is perfectly suited to carry out that containment strategy," he told The Guardian.

An army of white coats

Cuba's medical experience is not just prized at home. 

When Indigenous communities in Canada appealed to the federal government in April for help in dealing with COVID-19, their petition included an incongruous note: "Many Manitoba Chiefs have requested that Cuban doctors be fast-tracked to assist the communities."

That a G20 country should require assistance from a much poorer Caribbean island for medical staff – Cuba's GDP per capita is less than one-fifth that of Canada or Germany – was not as unusual as it appeared.

Cuba has a long history of sending its doctors abroad in a display of "medical diplomacy". Over the past six decades, doctors have been dispatched all over Latin America, Asia and Africa: in all, Cuba has reportedly sent over 400,000 medical staff to work in over 160 countries.

Cuban doctors provided assistance in Pakistan after the devastating 2005 earthquake, in Haiti during the 2010 cholera epidemic, and in West Africa in 2014 during the deadly Ebola outbreak.

Canada's Indigenous communities were not the only ones then to look to Havana for help as COVID-19 exploded worldwide, especially as countries saw their hospitals and medical staff become overwhelmed.

Since the start of the pandemic, Cuban medical brigades have been dispatched to about two dozen countries, including South Africa, Mexico, Mozambique and northern Italy, one of Europe's worst-hit regions, where they have worked alongside local staff doing round in hospitals and treating patients, regardless of the language barrier.

The number of requests flooding into Havana surprised even Cuba's Health Minister Jose Angel Portal Miranda, who tweeted in late March: "Cuba has extended its hand many times, but never this often in such a short time." He described the spate of missions as "unprecedented".

This engagement abroad has earned the "army of white coats" international plaudits, as well as thanks from the local communities they have helped.

But more than a selfless gesture, the missions are also a moneymaker for Cuba. Doctors volunteer knowing they will earn more than at home. And for Cuba's government, the program has long been a public relations success, as well as a crucial export: according to The Economist, medical services made up 46 percent of the country's exports last year and six percent of GDP.

Critics have argued the doctors are exploited and mistreated, with Havana pocketing most of their pay. U.S. Secretary of State Mike Pompeo blasted recently that countries requesting Cuban doctors were "helping the Cuban government turn a profit on human trafficking"

But back home, Cuba's doctors remain a source of pride. CNN images from Havana of medics returning from Lombardy, Italy, on Tuesday showed people in the streets cheering them and waving flags.