Cuban cardiologist Alexey Lopez, 59, is sleeping a bit better since his salary got a bump -- part of government efforts to stop its renowned health care system from bleeding doctors amid the island's worst economic crisis in decades.

But Lopez fears the wage boost will not be enough to lure back his colleagues who are among some 40,000 Cuban medical staff that quit in 2022 and 2023, according to official figures.

He told AFP "we were losing sleep" making ends meet before incentive bonuses were introduced last month for night and weekend shifts, seniority, and work in specialized or risky services.

The communist island has been battling sky-high inflation and shortages since the pandemic plus a tightening of US sanctions in 2021, combined with structural weaknesses, sent the economy into a tailspin.

The bleak circumstances have pushed some five percent of the population to flee, mostly to the United States, in the biggest wave of emigration since Fidel Castro's revolution.

Cuba's famed medical system has also taken a blow, with some health care workers leaving the country while others have ditched their white coats for better-paid work elsewhere, like the tourism industry.

To try to halt the exodus, some 400,000 doctors, nurses and technicians have been given the incentive bonuses.

The cardiologist Lopez, who works at Havana's Calixto Garcia Hospital, saw his salary more than double from 6,500 to 17,000 Cuban pesos with the bonuses, meaning he now earns $141 per month according to the official rate, but only $56 at the street rates which tend to govern prices.

"I know people who have quit and these measures are not yet enough to encourage them to come back," he told AFP.

Physiotherapist Amanda, who preferred not to give her surname, said that despite her salary being increased by a third, she will "have to find other solutions to generate money" to survive.

Deputy health minister Luis Fernando Navarro told AFP the measure aimed to "improve the living conditions of staff," even though he admits "this increase does not respond to the current cost of living in Cuba."

Navarro said the doctor shortage was most being felt in specialized fields.

He said that while the country has general practitioners in all of its health centers, "this is not the case for specialized care" in hospitals or "hyper-specialized care" for complex illnesses.

The country's universal health care system boasts 89 doctors for every 10,000 inhabitants, compared to 33 in France and 35 in the United States, according to the World Health Organization.

The export of skilled health care professionals in so-called "white coat diplomacy" has been a valuable source of foreign currency, and in some years -- such as 2018 -- was the country's main earner, bringing in some six billion dollars.

At home, Cuban doctors often have to buy their own stethoscopes and equipment.

With old heart monitors beeping in the background, Dr Lopez said the economic crisis was being felt "in shortages of doctors, equipment, and medicine."