Brazilian 99-year-old former WWII combatant Ermando Armelino Piveta gestures as he leaves the Armed Forces Hospital, after being treated for the coronavirus disease (COVID-19) and discharged, in Brasilia, Brazil, April 14, 2020.

Carlos Felipe Borges Bonfim, 34, sunbathes on the slab the day after being discharged from a hospital where he was being treated for the coronavirus disease (COVID-19 ) as its spread continues in Sao Paulo, Brazil, April 29, 2020. Picture taken April 29, 2020.

A patient recovering from the coronavirus disease (COVID-19) exercises in a swimming pool at the Casciana thermal baths spa, which has opened as a rehabilitation centre using its thermal water as part of treatment to help with respiratory difficulties, in Pisa, Italy, February 23, 2021.

Trader He Ximing, 52, a recovered COVID-19 patient who tested positive for the virus' antibodies after a number of negative tests, is seen during an interview with Reuters in his apartment after the lockdown was lifted in Wuhan, capital of Hubei province and China's epicentre of the novel coronavirus disease (COVID-19) outbreak, April 13, 2020.

Intensive Care Unit Nurse Merlin Pambuan, 66, is cheered by hospital staff as she walks out of the hospital where she spent 8 months with the coronavirus disease (COVID-19), at Dignity Health – St. Mary Medical Center, in Long Beach, California, U.S., December 21, 2020.

Cassia de Almeida, an ICU nurse of Sao Luiz Hospital, who was hospitalized with severe symptoms of coronavirus disease (COVID-19), hugs her daughter after being discharged in Sao Paulo, Brazil, May 30, 2020.

A doctor in protective suit visits a person suffering from the coronavirus disease (COVID-19) at her home in Bergamo, the epicentre of Italy's outbreak, April 16, 2020. Patients with symptoms that are not too severe are treated at home in Bergamo, to avoid overcrowding hospitals already overwhelmed with patients needing intensive care.

A patient recovering from coronavirus disease (COVID-19) waves as he is taken to a regular hospital room after spending more than fifty days at the intensive care unit (ICU) of the Infanta Sofia University hospital in Madrid, Spain, May 14, 2020.

Medical professionals release balloons as last patients leave the temporary field hospital at the Mane Garrincha Stadium, after being treated for the coronavirus disease (COVID-19) and discharged in Brasilia, Brazil, October 15, 2020.

Medical staff members surround patient Mang Phother, 61, who spent 16 days in the Intensive Care Unit (ICU) for the coronavirus disease (COVID-19), as he leaves the Clinique de l'Estree private hospital in Stains near Paris as the spread of the coronavirus disease continues in France, April 23, 2020.

Simon O'Brien, 36, looks on as his wife, Elizabeth Kerr, 31, reacts as she speaks, in a COVID-19 ward, days after they married in an ICU (Intensive Care Unit) when both had become critically ill with the coronavirus disease (COVID-19), and were uncertain of their chances of surviving, in Milton Keynes University Hospital, Milton Keynes, Britain, January 20, 2021.

Rusia Goes, a nurse who gave birth on April 26 hooked to a ventilator tube to help her breath as she battled severe symptoms of COVID-19, carries her daughter Luisa, her pre-mature birth baby, after she was released from the hospital, with her older daughter Julia and her husband Ednaldo Goes during the coronavirus disease (COVID-19) outbreak in Rio de Janeiro, Brazil, May 25, 2020.

Physiotherapist Ana Carolina Xavier of FamilyCare, a group specialising in mobile physiotherapy care, and who also works at the ICU of Lagoa-Barra field hospital for COVID-19 patients, applies a Brazilian physiotherapy method called RTA (Re-Balancing Thoracic-Abdominal), while attending a patient as she returns to work after recovering from the coronavirus disease (COVID-19), at the ICU, in Rio de Janeiro, Brazil July 2, 2020.

Yannis Ieremias, 70, is assisted by physiotherapist Georgia Bahou to keep his balance while walking during a session at the Theseus Rehabilitation Centre in Athens, Greece, February 1, 2021. Ieremias, who spend more than 50 days in the intensive care unit of an Athens hospital with the coronavirus disease (COVID-19), must undergo therapy to recover from mobility problems caused by his extend hospitalisation.

Francisco Garcia, 31, who spent almost four months in hospital with coronavirus disease (COVID-19), recovers at his home in Los Angeles, California, U.S., August 19, 2020.

A patient practices re-education exercises with physiotherapist Celine Pytlak at the post COVID-19 unit of the Bligny Hospital Center in Briis-sous-Forges during the outbreak of the coronavirus disease (COVID-19) in France, April 29, 2020.

Nurse Jorge Catarino, 35, holds a piece of plastic as part of his recovery therapy after suffering from the coronavirus disease (COVID-19) and being intubated for two weeks, at Physical Medicine and Rehabilitation Center of the Mexican Institute of Social Security (IMSS) in Mexico City, Mexico November 30, 2020.

Juan, 49, who recovered from the coronavirus disease (COVID-19) and whose father Jaime Florez, 80, died from the disease, poses for a photo as he holds a hat and the box containing Florez's ashes inside his apartment in Mexico City, Mexico September 11, 2020.

Belgian doctor Antoine Sassine, urologist at Chirec Delta Hospital, who survived the coronavirus disease (COVID-19) after 6 weeks in the intensive care unit and 3.5 weeks in a coma embraces his wife Alexandra as he leaves the hospital in Brussels, Belgium, April 19, 2020.

Judie Shape, 81, who had been diagnosed with coronavirus disease (COVID-19) and was a resident at Life Care Center of Kirkland, the long-term care facility linked to confirmed coronavirus cases in the state, leaves the center with her daughter, Lori Spencer, Kirkland, Washington, U.S. March 26, 2020.

Alessandra Said, 45, a doctor at Emergency Rescue Service (SAMU) embraces her mother Maria da Consolacao Said, 77, who recently recovered from the coronavirus disease (COVID-19), after monitoring her in Manaus, Brazil May 12, 2020.

Grocery worker Jackie Mayoral, 55, (C), who survived COVID-19 pauses for a moment of silence in front of a Dia de los Muertos, Day of the Dead, altar honoring 1,308 UFCW Local 770 grocery, drug store, and food processing essential union workers who have died from the coronavirus disease (COVID-19), in Los Angeles, California, U.S., October 26, 2020.

Wendolin Garcia, who recovered from the coronavirus disease (COVID-19) and lost 4 family members due to the COVID-19, watches TV on Christmas Eve while her children sleep, at her home in the municipality of Iztalapa, in Mexico City, Mexico December 24, 2020.

Florentina Martin, a 99 year-old woman who survived coronavirus disease (COVID-19), plays a digital puzzle with her great-grandson Pedro Valle at her home in Pinto, near Madrid, Spain, October 20, 2020.

Daw Thein Khin, a 100-year-old woman survivor of the coronavirus disease (COVID-19), poses for a photo at her home, amid the outbreak of the disease, in Yangon, Myanmar, October 13, 2020.

Recovered coronavirus patient John Walters takes a photo of his convalescent plasma donation bag at the Central Seattle Donor Center of Bloodworks Northwest during the coronavirus disease (COVID-19) global outbreak, in Seattle, Washington, U.S. September 2, 2020.

Geneva Wood, 90, who was a resident at Life Care Center of Kirkland, is pictured at home as her son, Keith Wood, prepares coffee after she recovered at Harborview Medical Center from coronavirus disease (COVID-19), during the coronavirus disease (COVID-19) outbreak, in Kirkland, Washington, U.S. March 24, 2020.

A nurse poses for a picture with a one-month-old Thai baby, the country's youngest coronavirus disease (COVID-19) patient that has successfully recovered, a day before being discharged from Bamrasnaradura Infectious Diseases Institute in Bangkok, Thailand April 22, 2020.

A volunteer wearing protective suit and face mask performs with a puppet to entertain children who were infected with the coronavirus disease (COVID-19) and have recovered in a quarantine ward, at a hospital in the holy city of Najaf, Iraq April 21, 2020.

Occupational Therapists Jason Smith and Grace Rowan assist recovering coronavirus patient Peter Dunn in walking again after the leaving intensive care unit at The Royal Blackburn Teaching Hospital in East Lancashire, following the outbreak of the coronavirus disease (COVID-19), in Blackburn, Britain, May 14, 2020.

Medical personnel in protective suits wave hands to a patient who is discharged from the Leishenshan Hospital after recovering from the coronavirus, in Wuhan, Hubei province, China March 1, 2020. China Daily via REUTERS

Claudio Facoetti, a 65-year-old man from the northern Italian city of Bergamo, near Milan, receives a farewell ceremony by intensive care nurses of the Saint Josef university clinic after recovering within six weeks from the coronavirus disease (COVID-19) in Bochum, Germany, May 9, 2020.

Brazilian judo coach, Diego Neves da Silva, 24, who suffers from the coronavirus disease (COVID-19) receives help from his friend, Paulo Vitor da Silva, at his home in Manaus, Brazil, January 31, 2021.

Eurenice Melo, 87, who suffers from coronavirus disease (COVID-19) undergoes physical therapy at her home in Manaus, Brazil March 2, 2021. Picture taken March 2, 2021.