Britain's Prince William and Catherine, Duchess of Cambridge meet with Head of Pharmacy Sotiris Antoniou, Respiratory Physio Isobel Fale and Medical Oncology Trainee and Chief Registrar Dr Myria Galazi as they visit St. Bartholomew's Hospital in London, Britain October 20, 2020. Matt Dunham/Pool via REUTERS

A female trainee, Reham Salhieh, works out at a gym, amid the spread of the coronavirus disease (COVID-19), in Riyadh, Saudi Arabia September 24, 2020. Picture taken September 24, 2020. REUTERS/Ahmed Yosri

Dancer Sabrina Olivieri, 23, from New Jersey, a trainee at the Jose Limon Dance Company, dances in front of the Revson Fountain in the Lincoln Center, home to the Metropolitan Opera House and New York City Ballet, who have had to cancel their shows due to the coronavirus disease (COVID-19) in Manhattan, New York City, U.S., September 26, 2020. REUTERS/Andrew Kelly

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a training center in Sanaa, Yemen September 1, 2020. Picture taken September 1, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a house in Sanaa, Yemen September 5, 2020. Picture taken September 5, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a training center in Sanaa, Yemen September 1, 2020. Picture taken September 1, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer performs drills with trainees at the yard of their house in Sanaa, Yemen September 5, 2020. Picture taken September 5, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer walks with a trainee on a street in Sanaa, Yemen September 8, 2020. Picture taken September 8, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a training center in Sanaa, Yemen September 1, 2020. Picture taken September 1, 2020. REUTERS/Nusaibah Almuaalemi TPX IMAGES OF THE DAY

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a house in Sanaa, Yemen September 5, 2020. Picture taken September 5, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a house in Sanaa, Yemen September 5, 2020. Picture taken September 5, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a training center in Sanaa, Yemen September 1, 2020. Picture taken September 1, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer practices self-defense moves with a trainee at a house in Sanaa, Yemen September 5, 2020. Picture taken September 5, 2020. REUTERS/Nusaibah Almuaalemi

Martial arts trainer Seham Amer performs drills with trainees at the yard of their house in Sanaa, Yemen September 5, 2020. Picture taken September 5, 2020. REUTERS/Nusaibah Almuaalemi

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Trainees learn how to build and operate an EUV machine at the training center at ASML Holding in Tainan, Taiwan, August 20, 2020. REUTERS/Ann Wang

Bride Sarneet Singh, a geriatric trainee at St Mary's, and groom Neil Bhadresha, a doctor at St Thomas, leave Kensington and Chelsea Register Office at Chelsea's old town hall, after getting married after guest restrictions were lifted, following the coronavirus disease (COVID-19) outbreak, in London, Britain August 15, 2020. REUTERS/Simon Dawson

People watch a live-stream of bride Sarneet Singh, a geriatric trainee at St Mary's, and groom Neil Bhadresha, a doctor at St Thomas, getting married at Kensington and Chelsea Register Office at Chelsea's old town hall, after guest restrictions were lifted, following the coronavirus disease (COVID-19) outbreak, in London, Britain August 15, 2020. REUTERS/Simon Dawson

People watch a live-stream of bride Sarneet Singh, a geriatric trainee at St Mary's, and groom Neil Bhadresha, a doctor at St Thomas, getting married at Kensington and Chelsea Register Office at Chelsea's old town hall, after guest restrictions were lifted, following the coronavirus disease (COVID-19) outbreak, in London, Britain August 15, 2020. REUTERS/Simon Dawson

People watch a live-stream of bride Sarneet Singh, a geriatric trainee at St Mary's, and groom Neil Bhadresha, a doctor at St Thomas, getting married at Kensington and Chelsea Register Office at Chelsea's old town hall, after guest restrictions were lifted, following the coronavirus disease (COVID-19) outbreak, in London, Britain August 15, 2020. REUTERS/Simon Dawson

Bride Sarneet Singh, a geriatric trainee at St Mary's, and groom Neil Bhadresha, a doctor at St Thomas, leave Kensington and Chelsea Register Office at Chelsea's old town hall after getting married, after guest restrictions were lifted following the coronavirus disease (COVID-19) outbreak, in London, Britain August 15, 2020. REUTERS/Simon Dawson

Bride Sarneet Singh, a geriatric trainee at St Mary's, and groom Neil Bhadresha, a doctor at St Thomas, pose for a picture after getting married at Kensington and Chelsea Register Office at Chelsea's old town hall, after guest restrictions were lifted following the coronavirus disease (COVID-19) outbreak, in London, Britain August 15, 2020. REUTERS/Simon Dawson

Bride Sarneet Singh, a geriatric trainee at St Mary's, and groom Neil Bhadresha, a doctor at St Thomas, pose for a picture after getting married at Kensington and Chelsea Register Office at Chelsea's old town hall, after guest restrictions were lifted following the coronavirus disease (COVID-19) outbreak, in London, Britain August 15, 2020. REUTERS/Simon Dawson

Britain's Prime Minister Boris Johnson talks to a paramedic and trainee paramedic, Darryl Dickson, all wearing masks, in an ambulance at the Northern Ireland Ambulance Service HQ during his visit to Belfast, Northern Ireland August 13, 2020. Brian Lawless/Pool via REUTERS

Britain's Prime Minister Boris Johnson talks to a paramedic and trainee paramedic, Darryl Dickson, all wearing masks, in an ambulance at the Northern Ireland Ambulance Service HQ during his visit to Belfast, Northern Ireland August 13, 2020. Brian Lawless/Pool via REUTERS

Britain's Prime Minister Boris Johnson elbow bumps trainee paramedic, Darryl Dickson, both wearing masks, in an ambulance at the Northern Ireland Ambulance Service HQ during his visit to Belfast, Northern Ireland August 13, 2020. Brian Lawless/Pool via REUTERS

Trainee doctors do a demonstration with medical dummy during a media visit to the Crown Prince Center For Training And Medical Research, in Riffa, Bahrain, June 18, 2020, REUTERS/Hamad I Mohammed.

A healthcare worker checks a trainee as she arrives to attend a training about mobile journalism at the office of Press House-Palestine, a media institution, as Palestinians ease the coronavirus disease (COVID-19) restrictions in Gaza City June 8, 2020. REUTERS/Mohammed Salem

A healthcare worker checks the body temperature of a trainee as she arrives to attend a training about mobile journalism at the office of Press House-Palestine, a media institution, as Palestinians ease the coronavirus disease (COVID-19) restrictions in Gaza City June 8, 2020. REUTERS/Mohammed Salem

A trainee is sanitized as she arrives to attend a training about mobile journalism at the office of Press House-Palestine, a media institution, as Palestinians ease the coronavirus disease (COVID-19) restrictions in Gaza City June 8, 2020. REUTERS/Mohammed Salem

Police trainees wearing personal protective equipment maintain social distancing in a train during a simulation exercise in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

Police trainees wearing personal protective equipment maintain social distancing at a train station during a simulation exercise in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

Police trainees wearing personal protective equipment maintain social distancing in a train during a simulation exercise in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

Police trainees wearing personal protective equipment maintain social distancing at a train station during a simulation exercise in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

Police trainees wearing personal protective equipment prepare to enter a train with social distancing measures during a simulation exercise in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

Police trainees wearing personal protective equipment maintain social distancing at a train station during a simulation exercise in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

A police trainee takes off her face shield to wipe her sweat during a simulation exercise at a train station, in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

Police trainees wearing personal protective equipment maintain social distancing at a train station during a simulation exercise in preparation for the resumption of train operations, amid the coronavirus disease (COVID-19) outbreak, in Manila, Philippines May 26, 2020. REUTERS/Eloisa Lopez

A trainee poses with a Pilatus PC-21 training aircraft during French Defence Minister Florence Parly's visit to the French Air Force pilot school at the BA 709 military air base of Cognac-Chateaubernard in Chateaubernard, France May 14, 2020. Mehdi Fedouach/Pool via REUTERS

French Defence Minister Florence Parly meets with servicemen and trainees during a visit to the French Air Force pilot school at the BA 709 military air base of Cognac-Chateaubernard in Chateaubernard, France May 14, 2020. Mehdi Fedouach/Pool via REUTERS

French Defence Minister Florence Parly meets with servicemen and trainees during a visit to the French Air Force pilot school at the BA 709 military air base of Cognac-Chateaubernard in Chateaubernard, France May 14, 2020. Mehdi Fedouach/Pool via REUTERS

French Defence Minister Florence Parly meets with servicemen and trainees during a visit to the French Air Force pilot school at the BA 709 military air base of Cognac-Chateaubernard in Chateaubernard, France May 14, 2020. Mehdi Fedouach/Pool via REUTERS

French Defence Minister Florence Parly meets with servicemen and trainees during a visit to the French Air Force pilot school at the BA 709 military air base of Cognac-Chateaubernard in Chateaubernard, France May 14, 2020. Mehdi Fedouach/Pool via REUTERS

French Defence Minister Florence Parly meets with servicemen and trainees during a visit to the French Air Force pilot school at the BA 709 military air base of Cognac-Chateaubernard in Chateaubernard, France May 14, 2020. Mehdi Fedouach/Pool via REUTERS

Trainee nurses Christin Schwibbe and Emma Stachelhaus leave the intensive care unit at the Asklepios clinic, as the spread of coronavirus disease (COVID-19) continues, in Pasewalk, Germany March 30, 2020. Picture taken March 30, 2020. REUTERS/Annegret Hilse

A trainee nurse Christin Schwibbe leaves the intensive care unit at the Asklepios clinic, as the spread of coronavirus disease (COVID-19) continues, in Pasewalk, Germany March 30, 2020. Picture taken March 30, 2020. REUTERS/Annegret Hilse

A passenger wearing a mask waits in line to check in for a flight as the Federal Aviation Administration (FAA) said it temporarily halted flights arriving at New York City airports and Philadelphia on Saturday after a trainee at the New York Air Route Traffic Control Center tested positive for coronavirus disease (COVID-19), at Miami International Airport, Miami, Florida, U.S., March 21, 2020. REUTERS/Carlos Barria

A passenger wearing a mask sits next to an airpot information screens as the Federal Aviation Administration (FAA) said it temporarily halted flights arriving at New York City airports and Philadelphia on Saturday after a trainee at the New York Air Route Traffic Control Center tested positive for coronavirus disease (COVID-19), at Miami International Airport, Miami, Florida, U.S., March 21, 2020. REUTERS/Carlos Barria

A coach instructs trainees at the KONE Academy of Finish elevators and escalators manufacturer KONE in Hanover, Germany, February 6, 2020. Picture taken February 6, 2020. REUTERS/Fabian Bimmer

A trainee works in an elevator at the KONE Academy of Finish elevators and escalators manufacturer KONE in Hanover, Germany, February 6, 2020. Picture taken February 6, 2020. REUTERS/Fabian Bimmer

A trainee works in an elevator at the KONE Academy of Finish elevators and escalators manufacturer KONE in Hanover, Germany, February 6, 2020. Picture taken February 6, 2020. REUTERS/Fabian Bimmer

A coach instructs trainees at the KONE Academy of Finish elevators and escalators manufacturer KONE in Hanover, Germany, February 6, 2020. Picture taken February 6, 2020. REUTERS/Fabian Bimmer

South Africa's President Cyril Ramaphosa looks on as German Chancellor Angela Merkel talks to Tiisetso Mafolo and Ditshego Sebothoma, trainees of BMW's Leadership Academy, during their visit at the BMW SA Group Plant in Rosslyn, Pretoria, South Africa, February 6, 2020. REUTERS/Siphiwe Sibeko

South Africa's President Cyril Ramaphosa greets Tiisetso Mafolo and Ditshego Sebothoma, trainees of BMW's Leadership Academy, as German Chancellor Angela Merkel looks on during their visit at the BMW SA Group Plant in Rosslyn, Pretoria, South Africa, February 6, 2020. REUTERS/Siphiwe Sibeko