Kate Ryan who is awaiting a liver transplant receives the AstraZeneca COVID-19 vaccine during the round for medically vulnerable people at the Aviva Stadium mass vaccination centre, amid the coronavirus disease (COVID-19) pandemic, in Dublin, Ireland, April 4, 2021. REUTERS/Clodagh Kilcoyne 

Kate Ryan who is awaiting a liver transplant receives the AstraZeneca COVID-19 vaccine during the round for medically vulnerable people at the Aviva Stadium mass vaccination centre, amid the coronavirus disease (COVID-19) pandemic, in Dublin, Ireland, April 4, 2021. REUTERS/Clodagh Kilcoyne 

People walk in a corridor of the hospital Auxilio Mutuo, that houses liver and kidney transplant centers, in San Juan, October 20, 2015. Puerto Rico is trying to build its medical tourism industry, from a current level of about $80 million a year to $300 million by 2017, as part of efforts to heal its chronically sick economy. Puerto Rico's potential as a transplant center is partly based on a macabre statistic - the Caribbean island had a murder and nonnegligent manslaughter rate of 19.2 per 100,000 people in 2014 compared to 4.5 per 100,000 in the United States according to Federal Bureau of Investigation data. Picture taken October 20, 2015. To match Feature USA-PUERTORICO/TRANSPLANTS REUTERS/Alvin Baez

The hospital Auxilio Mutuo, that houses liver and kidney transplant centers, is seen in San Juan, October 20, 2015. Puerto Rico is trying to build its medical tourism industry, from a current level of about $80 million a year to $300 million by 2017, as part of efforts to heal its chronically sick economy. Puerto Rico's potential as a transplant center is partly based on a macabre statistic - the Caribbean island had a murder and nonnegligent manslaughter rate of 19.2 per 100,000 people in 2014 compared to 4.5 per 100,000 in the United States according to Federal Bureau of Investigation data. Picture taken October 20, 2015. To match Feature USA-PUERTORICO/TRANSPLANTS REUTERS/Alvin Baez

Surgeon Juan Del Rio poses for a photograph at the hospital Auxilio Mutuo, that houses liver and kidney transplant centers, in San Juan, October 20, 2015. Puerto Rico is trying to build its medical tourism industry, from a current level of about $80 million a year to $300 million by 2017, as part of efforts to heal its chronically sick economy. Puerto Rico's potential as a transplant center is partly based on a macabre statistic - the Caribbean island had a murder and nonnegligent manslaughter rate of 19.2 per 100,000 people in 2014 compared to 4.5 per 100,000 in the United States according to Federal Bureau of Investigation data. Picture taken October 20, 2015. To match Feature USA-PUERTORICO/TRANSPLANTS REUTERS/Alvin Baez

Surgeon Juan Del Rio poses for a photograph at the hospital Auxilio Mutuo, that houses liver and kidney transplant centers, in San Juan, October 20, 2015. Puerto Rico is trying to build its medical tourism industry, from a current level of about $80 million a year to $300 million by 2017, as part of efforts to heal its chronically sick economy. Puerto Rico's potential as a transplant center is partly based on a macabre statistic - the Caribbean island had a murder and nonnegligent manslaughter rate of 19.2 per 100,000 people in 2014 compared to 4.5 per 100,000 in the United States according to Federal Bureau of Investigation data. Picture taken October 20, 2015. To match Feature USA-PUERTORICO/TRANSPLANTS REUTERS/Alvin Baez

Former France defender and Olympiakos Piraeus player Eric Abidal arrives for a news conference at Karaiskaki stadium in Piraeus, near Athens December 19, 2014. Abidal, who returned to playing after undergoing a liver transplant in April 2012, announced on Friday he was ending his career for 'personal reasons'. REUTERS/Alkis Konstantinidis (GREECE - Tags: SPORT SOCCER PROFILE) 

Former France defender and Olympiakos Piraeus player Eric Abidal reacts during a news conference at Karaiskaki stadium in Piraeus, near Athens December 19, 2014. Abidal, who returned to playing after undergoing a liver transplant in April 2012, announced on Friday he was ending his career for 'personal reasons'. REUTERS/Alkis Konstantinidis (GREECE - Tags: SPORT SOCCER PROFILE) 

Former France defender and Olympiakos Piraeus player Eric Abidal reacts during a news conference at Karaiskaki stadium in Piraeus, near Athens December 19, 2014. Abidal, who returned to playing after undergoing a liver transplant in April 2012, announced on Friday he was ending his career for 'personal reasons'. REUTERS/Alkis Konstantinidis (GREECE - Tags: SPORT SOCCER PROFILE) 

Former France defender and Olympiakos Piraeus player Eric Abidal speaks during a news conference at Karaiskaki stadium in Piraeus, near Athens December 19, 2014. Abidal, who returned to playing after undergoing a liver transplant in April 2012, announced on Friday he was ending his career for 'personal reasons'. REUTERS/Alkis Konstantinidis (GREECE - Tags: SPORT SOCCER PROFILE HEADSHOT) 

Former France defender and Olympiakos Piraeus player Eric Abidal speaks during a news conference at Karaiskaki stadium in Piraeus, near Athens December 19, 2014. Abidal, who returned to playing after undergoing a liver transplant in April 2012, announced on Friday he was ending his career for 'personal reasons'. REUTERS/Alkis Konstantinidis (GREECE - Tags: SPORT SOCCER PROFILE) 

Former France defender and Olympiakos Piraeus player Eric Abidal reacts during a news conference at Karaiskaki stadium in Piraeus, near Athens December 19, 2014. Abidal, who returned to playing after undergoing a liver transplant in April 2012, announced on Friday he was ending his career for 'personal reasons'. REUTERS/Alkis Konstantinidis (GREECE - Tags: SPORT SOCCER PROFILE) 

Barcelona's player Eric Abidal poses after their Spanish First division soccer league match against Mallorca at Camp Nou stadium in Barcelona, April 6, 2013. Abidal returned to the pitch two years after being diagnosed and treated for a liver tumour. Abidal's cousin Gerard had provided part of his liver for the transplant. The shirt reads: "Thanks to my cousin". REUTERS/Albert Gea (SPAIN - Tags: SPORT SOCCER HEALTH) 

Barcelona's player Eric Abidal poses after their Spanish First division soccer league match against Mallorca at Camp Nou stadium in Barcelona, April 6, 2013. Abidal returned to the pitch two years after being diagnosed and treated for a liver tumour. Abidal's cousin Gerard had provided part of his liver for the transplant. The shirt reads: "Thanks to my cousin". REUTERS/Albert Gea (SPAIN - Tags: SPORT SOCCER HEALTH) 

King's College Hospital liver transplant surgeon, Wayel Jassem, speaks during a news conference at the Royal Society in London March 15, 2013. A donated human liver has been kept alive, warm and functioning outside a human being on a newly-developed machine and then successfully transplanted into patients in a medical world first. REUTERS/Luke MacGregor (BRITAIN - Tags: HEALTH SCIENCE TECHNOLOGY) 

Director of transplant surgery at King's College Hospital, Nigel Heaton (L), speaks as Oxford University professor of biomedical engineering Constantin Coussios and Oxford University professor of transplantation Peter Friend (R) listen, during a news conference at the Royal Society in London March 15, 2013. A donated human liver has been kept alive, warm and functioning outside a human being on a newly-developed machine and then successfully transplanted into patients in a medical world first. REUTERS/Luke MacGregor (BRITAIN - Tags: HEALTH SCIENCE TECHNOLOGY) 

Oxford University professor of biomedical engineering, Constantin Coussios (L), speaks as Oxford University professor of transplantation, Peter Friend, listens during a news conference at the Royal Society in London March 15, 2013. A donated human liver has been kept alive, warm and functioning outside a human being on a newly-developed machine and then successfully transplanted into patients in a medical world first. REUTERS/Luke MacGregor (BRITAIN - Tags: HEALTH SCIENCE TECHNOLOGY) 

Oxford University professor of biomedical engineering, Constantin Coussios (L), listens to Oxford University professor of transplantation, Peter Friend, speak during a news conference at the Royal Society in London March 15, 2013. A donated human liver has been kept alive, warm and functioning outside a human being on a newly-developed machine and then successfully transplanted into patients in a medical world first. REUTERS/Luke MacGregor (BRITAIN - Tags: HEALTH SCIENCE TECHNOLOGY) 

Barcelona's Leo Messi walks to the stadium before the start of their Spanish First Division soccer match against Sevilla at Ramon Sanchez Pizjuan stadium in Seville March 17, 2012. Eric Abidal's season is almost certainly over and he is unlikely to represent France at Euro 2012 after his club Barcelona announced he will undergo a liver transplant. His t-shirt reads, "Abi you will win again." REUTERS/Marcelo del Pozo (SPAIN - Tags: SPORT SOCCER) 

Barcelona's Leo Messi (L) and teammates greet the crowd before the start of their Spanish First Division soccer match against Sevilla at Ramon Sanchez Pizjuan stadium in Seville March 17, 2012. Eric Abidal's season is almost certainly over and he is unlikely to represent France at Euro 2012 after his club Barcelona announced he will undergo a liver transplant. T-shirts read "Abi you will win again." REUTERS/Marcelo del Pozo (SPAIN - Tags: SPORT SOCCER) 

Barcelona's players are seen before the start of their Spanish First Division soccer match against Sevilla at Ramon Sanchez Pizjuan stadium in Seville March 17, 2012. Eric Abidal's season is almost certainly over and he is unlikely to represent France at Euro 2012 after his club Barcelona announced he will undergo a liver transplant. T-shirts read "Abi you will win again".
REUTERS/Marcelo del Pozo (SPAIN - Tags: SPORT SOCCER TPX IMAGES OF THE DAY) 

Barcelona's players pose before the start of their Spanish First Division soccer match against Sevilla at Ramon Sanchez Pizjuan stadium in Seville March 17, 2012. Eric Abidal's season is almost certainly over and he is unlikely to represent France at Euro 2012 after his club Barcelona announced he will undergo a liver transplant. T-shirts read "Abi you will win again".
REUTERS/Marcelo del Pozo (SPAIN - Tags: SPORT SOCCER) 

Debra Pennington (R) walks with people protesting against state Medicaid transplant budget cuts as she holds a picture of her husband Michael Allen Pennington, who needs a liver transplant in Phoenix, Arizona March 5, 2011.The measure enacted by Arizona Republican Governor Jan Brewer seeks to trim Medicaid spending in the desert state, which projects a 2011 budget deficit of $763.6 million and a full-year 2012 budget deficit of $1.15 billion, and has denied potentially lifesaving transplants to nearly 100 people. Two people have since died. REUTERS/Joshua Lott (UNITED STATES - Tags: HEALTH POLITICS BUSINESS) 

Liver transplant patient Anna Marceca, 7, waits in line to receive the H1N1 vaccine in Haltom City, Texas October 30, 2009. Tarrant County is distributing 1,600 injectable doses of the H1N1 vaccine to children ages 6 months to 18 years and pregnant women today. REUTERS/Jessica Rinaldi (UNITED STATES HEALTH) 

France's President Nicolas Sarkozy delivers a speech as Research Minister Valerie Pecresse (L) listens, after a visit at the liver transplant section of Villejuif Paul-Brousse hospital,Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE POLITICS HEALTH) 

France's President Nicolas Sarkozy delivers a speech as Research Minister Valerie Pecresse (L) listens, after a visit at the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE) 

France's President Nicolas Sarkozy delivers a speech after a visit at the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy was visiting the Paul-Brousse hospital to mark their 2500st liver transplant operation. REUTERS/Philippe Wojazer (FRANCE POLITICS HEALTH) 

France's President Nicolas Sarkozy (R) speaks with nurses as he arrives to visit the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE POLITICS HEALTH) 

France's President Nicolas Sarkozy (L) speaks with a patient as he visits the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE) 

France's President Nicolas Sarkozy (L) speaks with a patient (hidden by the computers) as he visits the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE) 

France's President Nicolas Sarkozy (L) and Paris Public hospital association (AP-HP) director Jean-Marie Le Guen (C) speak with a mother who holds a child as they visit the liver transplant section of Villejuif Paul-Brousse hospital,Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE) 

France's President Nicolas Sarkozy (L) checks a child temperature as Paris Public hospital association (AP-HP) director Jean-Marie Le Guen (C) looks on as they visit the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE) 

France's President Nicolas Sarkozy (2nd L) and Paris Public hospital association (AP-HP) director Jean-Marie Le Guen (3rd L) speak nurses as they visit the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE POLITICS HEALTH) 

France's President Nicolas Sarkozy (L) speaks with nurses as he arrives to visit the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE POLITICS HEALTH) 

France's President Nicolas Sarkozy (R) speaks with nurses as he arrives to visit the liver transplant section of Villejuif Paul-Brousse hospital, Paris suburb, September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE POLITICS HEALTH) 

France's President Nicolas Sarkozy (L) and Paris Public hospital association (AP-HP) director Jean-Marie Le Guen (2nd L) speak with mothers, one who holds a child, as they visit the liver transplant section of Villejuif Paul-Brousse hospital, near Paris on September 18, 2009. Sarkozy visits the Paul-Brousse Hospital to mark their 2,500th liver transplant operation. REUTERS/Philippe Wojazer (FRANCE POLITICS HEALTH) 

Apple Inc.'s Chief Executive Officer Steve Jobs (bottom row R) stepped back into the spotlight for the first time in nearly a year on September 9, 2009, drawing a standing ovation. Jobs, a pancreatic cancer survivor, returned to work in June after six months of medical leave, during which he underwent a liver transplant. Jobs is shown in this combination photographs dating (top row L to R) 2000, 2003, 2005,(bottom row L to R) 2006, 2008 and 2009. REUTERS/Files (UNITED STATES BUSINESS SCI TECH IMAGES OF THE DAY) 

Lorene Parker watches outside through a window at her house, which is in foreclosure in Detroit, Michigan December 11, 2008. Parker of Detroit fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

A view of Lorene Parker's house, which is in foreclosure in Detroit, Michigan December 11, 2008. Parker of Detroit fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker waits at a hall of the court for her appointment her on foreclosure house case in Detroit, Michigan December 11, 2008. Parker of Detroit fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker (R) washes the dishes as her daughter Latifa walks behind her at her her house, which is in foreclosure, in Detroit December 11, 2008. Parker fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker stands at her house, which is in foreclosure, in Detroit December 11, 2008. Parker fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker cleans her house, which is in foreclosure, in Detroit December 11, 2008. Parker fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker leaves the court house with her attorney after news that her foreclosure case is postponed to next year in Detroit, Michigan December 11, 2008. Parker fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and was scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker (L) leaves the court house with her attorney after news that her foreclosure case is postponed to next year in Detroit, Michigan December 11, 2008. Parker fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and was scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker (R) and her attorney smile as the news of her foreclosure case is postponed to next year in Detroit, Michigan December 11, 2008. Parker fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and was scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker waits at a hall of the court for her appointment on her foreclosure house case in Detroit, Michigan December 11, 2008. Parker fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker watches outside through a window at her house, which is in foreclosure in Detroit, Michigan December 11, 2008. Parker of Detroit fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Lorene Parker stands next to boxes of clothes, packed in preparation of her foreclosure decision, in Detroit, Michigan December 11, 2008. Parker of Detroit fell behind on her mortgage with Bank of America when she had large medical bills from heart and liver double transplant. Parker's home is in foreclosure and scheduled for sheriff sale on Thursday in court. REUTERS/Carlos Barria (UNITED STATES) 

Surgeons operate to extract the liver and the kidneys from a brain-dead woman at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin in this January 12, 2008 file picture. Germany's doctors are holding their annual 'Deutscher Aerztetag' (German doctors day) meeting in the German city of Ulm May 20, 2008. REUTERS/Fabrizio Bensch/files (GERMANY) 

A nurse prepares a brain-dead woman for surgery to extract her liver and kidneys for transplantation, in the intensive care department at the Unfallkrankenhaus Berlin (UKB) in Berlin in this January 12, 2008 file picture. Germany's doctors are holding their annual 'Deutscher Aerztetag' (German doctors day) meeting in the German city of Ulm May 20, 2008. REUTERS/Fabrizio Bensch/Files (GERMANY) 

Surgeons extract the liver and kidneys of a brain-dead woman for organ transplant donation at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

Surgeons extract the liver and kidneys of a brain-dead woman for organ transplant donation at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

Surgeons extract the liver and kidneys of a brain-dead woman for organ transplant donation at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

Surgeons extract the liver and kidneys of a brain-dead woman for transplantation donation at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

Surgeons extract the liver and kidneys of a brain-dead woman for transplantation donation at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

Surgeons extract the liver and kidneys of a brain-dead woman for donation at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

Medical personnel bring a brain-dead woman into an operating room to extract the liver and kidneys for donation at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

A surgeon hands over to a colleague a plastic bag containing a kidney after an operation to extract the liver and the kidneys from a brain-dead woman at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were be transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY) 

Surgeons pack a plastic bag containing a liver after an operation to extract the liver and the kidneys from a brain-dead woman at the Unfallkrankenhaus Berlin (UKB) hospital in Berlin January 12, 2008. The vital organs were be transported for transplantation to patients in three German cities. REUTERS/Fabrizio Bensch (GERMANY)