MONTEVIDEO • As a second deadly wave of Covid-19 batters Latin America, images have emerged of desperate people lining up for days to buy oxygen to ease the suffering of infected loved ones fighting for breath.

As demand soars, prices have skyrocketed and families have had to scrape together their last cents to pay for supplies of the essential gas.

On Jan 14 alone, a researcher estimates more than 100 people died of asphyxiation at hospitals in Brazil's northern Amazonas state.

According to the World Health Organisation, about one in five people with Covid-19 requires oxygen therapy to relieve respiratory distress. With more than 19 million recorded infections to date - likely an under-count, according to experts - this means almost four million people in Latin America have required oxygen therapy since the outbreak began.

Public health non-governmental organisation Path, which compiles a Covid-19 Oxygen Needs Tracker, says more than half of the hospitals in low-and middle-income countries - a category that includes most of Latin America - have an inconsistent supply of medical oxygen, or lack it entirely.

On a world map produced by Path to show daily oxygen needs, Brazil is marked with a large orange dot, indicating demand for some 327,000 cylinders, followed by Mexico with 89,700 cylinders, Colombia with 76,700, Argentina 56,200, and Peru 36,700.

Access can be thwarted by shortages in everything, from money to buy the oxygen to clinics to administer it, electricity to produce it, and navigable roads by which to transport the cylinders, said Path's senior market dynamics officer Lisa Smith.

Latin America's death toll of more than 610,000 is second only to that of Europe, which is about 762,000. Brazil and Mexico account for more than half of the region's deaths, with 228,000 and 162,000, respectively, and rank second and third in terms of mortality worldwide.

Peru is proportionally the hardest hit, with 125 deaths per 100,000 of its population of 33 million.

Brazil's Amazonas state and its capital Manaus were particularly assailed by the second wave this year, quickly running out of hospital beds, oxygen and burial space.

By mid-January, daily demand for oxygen in Amazonas was about 76,000 cubic m and supply at a mere 28,200 cubic m.

In Peru, the price of a 10 cubic m tank varies widely - between US$330 (S$438) and US$690 - while a cubic m of oxygen sells for anything between US$5 and US$13.

In Mexico, the authorities say they have not detected any shortage or hoarding of oxygen. However, there was a 700 per cent increase in demand between Dec 20 and Jan 20, and a shortage of cylinders. On the Mexican black market, consumers say they are paying 45,000 pesos (S$2,970) for a 9,500-litre tank and 32,000 pesos for a 6,000-litre tank, about triple the normal price.

In impoverished Nicaragua, the price of a tank of oxygen could be as high as US$1,500, according to Dr Roger Pasquier, president of the Nicaraguan Anaesthesiology Association.

AGENCE FRANCE-PRESSE