An Ecuadorean woman in coronavirus-ravaged Guayaquil city learned on Friday that her sister was alive, weeks after cremating a misidentified body health authorities had released to her after declaring her sibling dead.

Alba Maruri, 74, was admitted to an intensive care unit on March 27 suffering from a high fever and difficulty breathing, and medical personnel told her family later that day that she had died, Maruri's sister Aura said by telephone.

A week later, health authorities released what they thought were Maruri's remains to her relatives, who had the body cremated.

On Friday, health workers came to the family's home to speak to them.

"An ambulance arrived with a doctor, a psychiatrist and the social worker. They apologised, and they tell us 'Your sister is alive,' and we were in shock," said Aura Maruri. "It is a miracle of God what has happened."

Maruri was suspected to have contracted COVID-19, the respiratory disease caused by the novel coronavirus, but was never diagnosed with it because she was not tested.

Her family was not able to visit her until Saturday because of curfew measures enacted to prevent the continued spread of the disease.

Aura Maruri says she does not know what to do with the ashes of the body they received by mistake.

"I couldn't sleep because I was afraid they would take her (remains) to those containers for the dead," said Maruri, referring to refrigerated containers set up as mobile morgues as the pandemic spread through Guayaquil.

"There was a failure by the hospital."

Overwhelmed health system

The incident underlines the difficulties facing Ecuador, where the coronavirus pandemic has overwhelmed the health system and left sanitary workers struggling to collect and identify the burgeoning number of bodies.

Reuters was unable immediately to obtain comment from Alba Maruri or from Abel Gilbert Ponton Hospital, where she is still being treated but is no longer in intensive care.

Health Minister Juan Carlos Zevallos told reporters that the case was under investigation, adding that health authorities guarantee the identification of corpses and hospitals keep track of the deceased.

The country has recorded nearly 23,000 cases of the coronavirus, 576 deaths, and another 1,060 people who are suspected to have died from it.

But the government recognises that the total number of deaths during the pandemic has been much higher than normal, and that many have died before being tested.