Snorkelling masks are being used to make ventilators for hospitals in the epicentre of Europe’s coronavirus outbreak.

Italian engineers came up with the idea to 3D print respiratory valves, a crucial part of the makeshift mask that connects it to an oxygen tube.

The start-up business behind the masks, Isinnova, got involved after founder Cristian Fracassi, heard about the valve shortage by word of mouth in Italy’s Lombardy region, the worst hit of the virus outbreak.

“We were told the hospital was desperately looking for more valves,” Mr Fracassi told the Daily Mail.

“They're called Venturi valves and are impossible to find at the moment, production can't keep up with demand.”

The company plans to make 100 of the valves a day to hand out to doctors trying to get the crisis under control.

Ventilators are used by coronavirus patients suffering from respiratory complications — the most severe symptoms of the infection — and many hospitals are facing shortages of them.

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The hospital Isinnova is helping is in Chiari, near Brescia.

“When we heard about the shortage, we got in touch with the hospital immediately,” Mr Fracassi told the Mail.

“We printed some prototypes, the hospital tested them and told us they worked. So we printed 100 valves and I delivered them personally.”

At least 10 patients were using equipment containing the valves by the evening.

Mr Fracassi said it didn’t cost much to make the valves, which are made of plastic.

The outbreak has killed more than 6000 Italians, the highest death toll of any country, and pushed the health system to the breaking point.

Italy has seen at least 18 doctors with the coronavirus die.

Doctors and nurses across the world have pleaded for supplies such as masks and ventilators.

“There’s a wild race to get surgical masks,” Francois Blanchecott, a biologist on the front lines of testing, told France Inter radio.

Doctors have scrounged for masks from construction workers and factory floors.