Daniel Perez writes on a wooden heart the names of his friends who died, during a memorial in honor of the people who died from the coronavirus disease (COVID-19), in Ciudad Juarez, Mexico October 23, 2021. REUTERS/Jose Luis Gonzalez 

A man writes on a tape attached to a windmill in memory of a friend and other people who died due to the coronavirus disease (COVID-19) in Sao Paulo, Brazil October 6, 2021. It reads "For those who are gone". REUTERS/Amanda Perobelli 

Pople write on poster during a protest over the Thai government's handling of the coronavirus disease (COVID-19) pandemic and to demand Prime Minister Prayuth Chan-ocha's resignation, in Bangkok, Thailand, September 3, 2021. REUTERS/Soe Zeya Tun 

1st grader Joseph stands while his mother writes his name on a name tag before entering Benbrook Elementary School on the first day of school amid the coronavirus disease (COVID-19) pandemic in Houston, Texas, U.S., August 23, 2021. REUTERS/Go Nakamura 

A woman writes a message on a greeting card, as part of a display for the Postal Museum's COVID-19 project at the O2 Arena, in London, Britain, July 19, 2021. REUTERS/Beresford Hodge 

A person writes a message on a greeting card, as part of a display for the Postal Museum's COVID-19 project at the O2 Arena, in London, Britain, July 19, 2021. REUTERS/Beresford Hodge 

A patient suffering from the coronavirus disease (COVID-19) writes a message on her mobile phone at Hospital del Mar, where an additional ward has been opened to deal with an increase in coronavirus patients in Barcelona, Spain July 15, 2021. REUTERS/Nacho Doce 

A health worker writes on the glass of a bus the time workers at the Irish auto parts manufacturer Aptiv were vaccinated with a dose of the Pfizer-BioNTech coronavirus disease (COVID-19) vaccine during a mass vaccination program for employees at the Mexico Technical Center in Ciudad Juarez, Mexico July 12, 2021. REUTERS/Jose Luis Gonzalez 

Health workers write a sign as they attend a demonstration in front of the National Palace to ask Mexico's government employment stability as the coronavirus disease (COVID-19) outbreak continues in Mexico City, Mexico July 6, 2021. The sign reads: "Yesterday heroes, today unemployed. IMSS, INER, Citibanamex". REUTERS/Edgard Garrido 

New York City Schools Chancellor Meisha Porter (R) embraces workers at a coronavirus disease (COVID-19) vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A teenage student rolls up his sleeve to receive a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) during a vaccination event for local adolescents and adults, outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A local resident receives a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19), during a vaccination event for adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A man looks through a fence at a coronavirus disease (COVID-19) vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A small group of anti-vaccine demonstrators protest outside a public coronavirus disease (COVID-19) vaccination event for local adolescents and adults, outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A small group of anti-vaccine demonstrators protest outside a public coronavirus disease (COVID-19) vaccination event for local adolescents and adults, outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A local resident eats ice cream at a coronavirus disease (COVID-19) vaccination event for adolescents and adults, outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

72-year-old Jay Hernandez receives a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19), during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

Anti-vaccine demonstrators protest outside a public coronavirus disease (COVID-19) vaccination event for adolescents and adults, outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A man looks through a fence at a coronavirus disease (COVID-19) vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

Anti-vaccine demonstrators protest outside a public coronavirus disease (COVID-19) vaccination event for adolescents and adults, outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

An anti-vaccine demonstrator holds a placard as he argues with a local resident outside a public vaccination event for adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

Jarmal Samuels escorts his 14-year-old daughter Aniyah Jennings past a small group of anti-vaccine demonstrators as they arrive for Aniyah to receive a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19), during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

14-year-old Aniyah Jennings embraces her father Jarmal Samuels after receiving a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

An anti-vaccine demonstrator yells outside a public vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A small group of anti-vaccine demonstrators protest outside a public vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

A teenage student receives a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

14-year-old Aniyah Jennings holds hands with her father Jarmal Samuels, just before receiving a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar TPX IMAGES OF THE DAY 

Registered nurse Sheba Phillip administers a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) to 14-year-old Angel Rodriguez, during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

12-year-old Justing Concepcion receives a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19) from registered nurse Angela Nyarko, during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

New York City Schools Chancellor Meisha Porter gives the thumbs up to 14-year-old Angel Rodriguez, after he received a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19), during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

Registered nurse Sheba Phillip prepares a syringe with a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19), during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

Registered Nurse Sheba Phillip prepares a syringe with a dose of the Pfizer-BioNTech vaccine for the coronavirus disease (COVID-19), during a vaccination event for local adolescents and adults outside the Bronx Writing Academy school in the Bronx borough of New York City, New York, U.S., June 4, 2021. REUTERS/Mike Segar 

Demonstrators hold the flag of the Misak people and Colombia's national flag while standing on the pedestal of the statue of South American independence leader Simon Bolivar during anti-government protests demanding the end to police violence, economic support as the coronavirus disease (COVID-19) pandemic batters incomes, and the withdrawal of a health reform, in Bogota, Colombia May 12, 2021. The writing on the mock coffin reads "The health reform wants us all in a box." REUTERS/Nathalia Angarita 

Demonstrators hold the flag of the Misak people while standing on the pedestal of the statue of South American independence leader Simon Bolivar during anti-government protests demanding the end to police violence, economic support as the coronavirus disease (COVID-19) pandemic batters incomes, and the withdrawal of a health reform, in Bogota, Colombia May 12, 2021. The writing on the mock coffin reads "The health reform wants us all in a box." REUTERS/Nathalia Angarita TPX IMAGES OF THE DAY 

A man wearing a protective face mask walks past writing on a wall that says 'no worries', as a phased reopening following Government guidance begins, after an extended lockdown due to the coronavirus disease (COVID-19) outbreak, in Dublin, Ireland, May 10, 2021. REUTERS/Clodagh Kilcoyne 

A firefighter administers a dose of the "Comirnaty" Pfizer BioNTech COVID-19 vaccine in a vaccination center in Reze near Nantes as part of the coronavirus disease (COVID-19) vaccination campaign in France, May 6, 2021. REUTERS/Stephane Mahe 

Rohan Aggarwal, 26, a resident doctor treating patients suffering from the coronavirus disease (COVID-19), writes down notes during his 27-hour shift at Holy Family Hospital in New Delhi, India, May 1, 2021. "If a patient has a fever, and I know he's sick but he's not requiring oxygen, I can't admit him," said Aggarwal. "That's the criteria. People are dying on the streets without oxygen. So people who don't require oxygen, even if they are sick, we don't admit them usually," he added. "Another choice is I have an old male and I have a young guy. Both are requiring high-flow oxygen; I have only one bed in the ICU. And I can't be emotional at that time, that he is a father to someone. The young have to be saved." REUTERS/Danish Siddiqui SEARCH "SIDDIQUI AGGARWAL" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES 

A nurse writes on a national flag during a symbolic protest and tribute for health workers on Labour Day, amid the spread of the coronavirus disease (COVID-19), in Brasilia, Brazil May 1, 2021. REUTERS/Ueslei Marcelino 

Dr. Mayank Amin writes a coronavirus disease (COVID-19) vaccination card for Donald B. Williams, a 101-year-old homebound patient, after he received his COVID-19 vaccine in Collegeville, Pennsylvania, U.S., April 29, 2021. REUTERS/Hannah Beier 

A demonstrator is being detained during a protest against the government, as it is seeking to block an approval made by Chile's lawmakers that would allow citizens to make another withdrawal from their privately-held pensions savings to combat economic hardship generated by the coronavirus disease pandemic (COVID-19), in Santiago, Chile April 23, 2021. The writing on the wall reads "Vengeance." REUTERS/Pablo Sanhueza 

A medical staffer writes down details of a woman who received the AstraZeneca vaccine against the coronavirus disease (COVID-19), at a medical center in Taiz, Yemen April 22, 2021. Picture taken April 22, 2021. REUTERS/Anees Mahyoub 

Venezuela's opposition leader Juan Guaido gestures while wearing a face mask with the writing "Vaccines, now!" during a protest to demand that all people get vaccinated against the coronavirus disease (COVID-19), in Caracas, Venezuela April 17, 2021. REUTERS/Leonardo Fernandez Viloria 

A person writes "Vaccines, now!" on the face mask of a healthcare worker during a protest to demand that all people get vaccinated against the coronavirus disease (COVID-19), in Caracas, Venezuela April 17, 2021. REUTERS/Leonardo Fernandez Viloria TPX IMAGES OF THE DAY 

Venezuelan doctor Leonardo Acosta writes prescriptions for his patient Mauricio Forgione during a home treatment for the coronavirus disease (COVID-19), as Forgione's wife Laura Martinez looks on, in Caracas, Venezuela April 16, 2021. Picture taken April 16, 2021. REUTERS/Leonardo Fernandez Viloria 

Samantha Wiik's fourth grade class writes what the coronavirus disease (COVID-19) means to them at Kratzer Elementary School in Allentown, Pennsylvania, U.S. April 13, 2021. Picture taken April 13, 2021. REUTERS/Hannah Beier 

A woman wears a face mask as restaurant and small business owners gather during a protest calling for their businesses to be allowed to re-open, despite no authorization for the demonstration by the government, amid the coronavirus disease (COVID-19) outbreak, in Rome, Italy, April 12, 2021. The writing on the face mask reads: "Open!". REUTERS/Yara Nardi 

Long COVID sufferer Teresa Dominguez, 55, a social worker specialising in disabilities, poses for a photograph taken through blue plastic, in Collado Villalba, Spain, March 4, 2021. The photograph was taken through blue plastic to visualise the effects of long COVID. Dominguez had only missed work when she gave birth to her children. The "mental mist", as she describes her inability to concentrate, and permanent fatigue after performing the simplest of everyday tasks have constrained her life for the past year, since her March 2020 coronavirus infection. "I started writing a diary because when doctors asked me about my symptoms, I couldn't remember many of them. At first doctors didn't know much about long COVID and I felt like I could help them out and others in my situation by providing them with that information. It has often been difficult to make them believe that we are really sick, that we are not making this up," she said. REUTERS/Susana Vera SEARCH "SPAIN LONGCOVID" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY. 

A diary notebook belonging to long COVID sufferer Teresa Dominguez, 55, a social worker specialising in disabilities, is seen photographed through blue plastic, in Collado Villalba, Spain, March 4, 2021. The photograph was taken through blue plastic to visualise the effects of long COVID. Dominguez had only missed work when she gave birth to her children. The "mental mist", as she describes her inability to concentrate, and permanent fatigue after performing the simplest of everyday tasks have constrained her life for the past year, since her March 2020 coronavirus infection. "I started writing a diary because when doctors asked me about my symptoms, I couldn't remember many of them. At first doctors didn't know much about long COVID and I felt like I could help them out and others in my situation by providing them with that information. It has often been difficult to make them believe that we are really sick, that we are not making this up," she said. REUTERS/Susana Vera SEARCH "SPAIN LONGCOVID" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES 

An exercise band, a ball and a seed bag belonging to long COVID sufferer Jorge Martin, 44, the head of a higher-education association, are photographed through blue plastic, in Ansoain, northern Spain, March 17, 2021. The photograph was taken through blue plastic to visualise the effects of long COVID. Martin has been off work for more than a year due to long COVID. He developed double pneumonia when he got infected with coronavirus during the first wave of the disease. He has been battling with cognitive difficulties and a long list of physical problems ever since. "I would not have pictured myself at my age using rehabilitation tools, but I've welcomed them because they help me with my physical aches and provide me with some relief from the distress of looking at the calendar and realising that a year has gone by and I'm still not recovered," he said. Martin is worried about the toll the disease is taking on his job. "I forget the names of family members, even my own license plate. The other day, I was trying to write something down and I realised I was writing again what I had written two days before. My job is intellectual, what's going to happen if this gets worse?" REUTERS/Susana Vera SEARCH "SPAIN LONGCOVID" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES 

Long COVID sufferer Jorge Martin, 44, the head of a higher-education association, poses for a photograph taken through blue plastic, in Ansoain, northern Spain, March 17, 2021. The photograph was taken through blue plastic to visualise the effects of long COVID. Martin has been off work for more than a year due to long COVID. He developed double pneumonia when he got infected with coronavirus during the first wave of the disease. He has been battling with cognitive difficulties and a long list of physical problems ever since. "I would not have pictured myself at my age using rehabilitation tools, but I've welcomed them because they help me with my physical aches and provide me with some relief from the distress of looking at the calendar and realising that a year has gone by and I'm still not recovered," he said. Martin is worried about the toll the disease is taking on his job. "I forget the names of family members, even my own license plate. The other day, I was trying to write something down and I realised I was writing again what I had written two days before. My job is intellectual, what's going to happen if this gets worse?" REUTERS/Susana Vera SEARCH "SPAIN LONGCOVID" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES 

A combination picture shows long COVID sufferer Teresa Dominguez, 55, a social worker specialising in disabilities, posing for a photograph taken through blue plastic, and her diary notebook photographed through blue plastic, in Collado Villalba, Spain, March 4, 2021. The photographs were taken through blue plastic to visualise the effects of long COVID. Dominguez had only missed work when she gave birth to her children. The "mental mist", as she describes her inability to concentrate, and permanent fatigue after performing the simplest of everyday tasks have constrained her life for the past year, since her March 2020 coronavirus infection. "I started writing a diary because when doctors asked me about my symptoms, I couldn't remember many of them. At first doctors didn't know much about long COVID and I felt like I could help them out and others in my situation by providing them with that information. It has often been difficult to make them believe that we are really sick, that we are not making this up," she said. REUTERS/Susana Vera SEARCH "SPAIN LONGCOVID" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY. 

A combination picture shows long COVID sufferer Jorge Martin, 44, the head of a higher-education association, posing for a photograph taken through blue plastic, and an exercise band, a ball and a seed bag belonging to Martin photographed through blue plastic, in Ansoain, northern Spain, March 17, 2021. The photographs were taken through blue plastic to visualise the effects of long COVID. Martin has been off work for more than a year due to long COVID. He developed double pneumonia when he got infected with coronavirus during the first wave of the disease. He has been battling with cognitive difficulties and a long list of physical problems ever since. "I would not have pictured myself at my age using rehabilitation tools, but I've welcomed them because they help me with my physical aches and provide me with some relief from the distress of looking at the calendar and realising that a year has gone by and I'm still not recovered," he said. Martin is worried about the toll the disease is taking on his job. "I forget the names of family members, even my own license plate. The other day, I was trying to write something down and I realised I was writing again what I had written two days before. My job is intellectual, what's going to happen if this gets worse?" REUTERS/Susana Vera SEARCH "SPAIN LONGCOVID" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES 

Venezuelan doctor Leonardo Acosta writes prescriptions for his patient Hogla Larez during a home treatment for the coronavirus disease (COVID-19), as Larez's daughter Aranza Valero looks on, in Caracas, Venezuela April 11, 2021. Picture taken April 11, 2021. REUTERS/Leonardo Fernandez Viloria 

A person writes a message on the National Covid Memorial Wall beside St Thomas' Hospital set as a memorial to all those who have died so far in the UK from the coronavirus disease (COVID-19), in London, Britain, April 8, 2021. REUTERS/Hannah McKay 

A person writes a message on the National Covid Memorial Wall beside St Thomas' Hospital set as a memorial to all those who have died so far in the UK from the coronavirus disease (COVID-19), in London, Britain, April 8, 2021. REUTERS/Hannah McKay 

A person writes a message on the National Covid Memorial Wall beside St Thomas' Hospital set as a memorial to all those who have died so far in the UK from the coronavirus disease (COVID-19), in London, Britain, April 8, 2021. REUTERS/Hannah McKay 

A man writes on the National Covid Memorial wall beside St Thomas' hospital set as a memorial to all those who have died so far in the UK from the coronavirus disease (COVID-19), amid the coronavirus pandemic in London, Britain April 8, 2021. REUTERS/Hannah McKay TPX IMAGES OF THE DAY 

A man walks past a graffiti of two people kissing while wearing face masks and the writing "In the face of the new strain, face mask for sure" amid a spike in infections of the coronavirus disease (COVID-19) that has led the government to extend lockdown measures, in Caracas, Venezuela April 6, 2021. REUTERS/Leonardo Fernandez Viloria 

A performing artist writes a message protesting the lack of financial support for the arts during the coronavirus disease (COVID-19) pandemic in Cape Town, South Africa, March 27, 2021. Picture taken March 27, 2021. REUTERS/Mike Hutchings 

A woman writes a name of her deceased loved one at the Old Town Square where thousands of crosses have been painted on a pavement to commemorate the first anniversary since the death of the first Czech coronavirus disease (COVID-19) patient in Prague, Czech Republic, March 25, 2021. Picture taken March 25, 2021. REUTERS/David W Cerny