Brigitte Latrille, triple medallist and Olympic champion of fencing in 1980 and one of the four specialists in the world to raise leeches for plastic and reconstructive surgery, holds a jar with leeches as she poses in the laboratory of the Ricarimpex company in Eysines, Southwestern France, December 5, 2016. Picture taken December 5, 2016. REUTERS/Regis Duvignau 

Cocoons, each containing about 20 individuals leeches which will be used on average 18 months later, are seen at the Ricarimpex laboratory in Eysines, Southwestern France, July 22, 2016. The leech, Hirudo medicinalis, is an invertebrate 3 cm long in adulthood which after being considered indispensable in the 19th century to cure many affections such as osteoarthritis, phlebitis, tension, then fell in desuetude while it harboured qualities that made it indispensable today in plastic surgery. Picture taken July 22, 2016. REUTERS/Regis Duvignau 

A leech in quarantine is seen in a jar at the Ricarimpex laboratory in Eysines, Southwestern France, July 22, 2016. The leech, Hirudo medicinalis, is an invertebrate 3 cm long in adulthood which after being considered indispensable in the 19th century to cure many affections such as osteoarthritis, phlebitis, tension, then fell in desuetude while it harboured qualities that made it indispensable today in plastic surgery. Picture taken July 22, 2016. REUTERS/Regis Duvignau TPX IMAGES OF THE DAY

A researcher checks leeches in quarantine in a jar at the Ricarimpex laboratory in Eysines, Southwestern France, July 22, 2016. The leech, Hirudo medicinalis, is an invertebrate 3 cm long in adulthood which after being considered indispensable in the 19th century to cure many affections such as osteoarthritis, phlebitis, tension, then fell in desuetude while it harboured qualities that made it indispensable today in plastic surgery. Picture taken July 22, 2016. REUTERS/Regis Duvignau 

Practitioner Al Sheikh Mohamed El-Sayed uses a leech, which sucks blood from a patient, with another form of cupping therapy inside a treatment room at a medical center in Shubra El-Kheima on the outskirts of Cairo, Egypt, August 13, 2016. Hijama or cupping therapy, an ancient treatment that uses glass cups and suction to help circulate blood and relieve muscle tension, was put into the spotlight during the Olympics after prominent athletes like U.S swimmer Michael Phelps hit the pool in Rio with circular red marks on his back. Picture taken August 13, 2016. REUTERS/Amr Abdallah Dalsh 

Practitioner Al Sheikh Mohamed El-Sayed uses a leech, which sucks blood in the mouth, with another form of cupping therapy inside a treatment room at a medical center in Shubra El-Kheima on the outskirts of Cairo, Egypt, August 13, 2016. Hijama or cupping therapy, an ancient treatment that uses glass cups and suction to help circulate blood and relieve muscle tension, was put into the spotlight during the Olympics after prominent athletes like U.S swimmer Michael Phelps hit the pool in Rio with circular red marks on his back. Picture taken August 13, 2016. REUTERS/Amr Abdallah Dalsh 

Actor Allen Leech arrives on the red carpet for the annual White House Correspondents Association Dinner in Washington, U.S., April 30, 2016. REUTERS/Jonathan Ernst 

The cast of Downton Abbey, from left, Phyllis Logan, Tom Cullen, Lesley Nicol, Sophie McShera, Joanne Froggatt, Raquel Cassidy, Kevin Doyle,Tom Cullen, Allen Leech, and Jeremy Swift, hold their awards for Outstanding Performance by an Ensemble in a Drama Series during the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

The cast of Downton Abbey, from left, Phyllis Logan, Tom Cullen, Lesley Nicol, Sophie McShera, Joanne Froggatt, Raquel Cassidy, Kevin Doyle,Tom Cullen, Allen Leech, and Jeremy Swift, hold their awards for Outstanding Performance by an Ensemble in a Drama Series during the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

The cast of Downton Abbey, from left, Phyllis Logan, Tom Cullen, Lesley Nicol, Sophie McShera, Joanne Froggatt, Raquel Cassidy, Kevin Doyle,Tom Cullen, Allen Leech, and Jeremy Swift, hold their awards for Outstanding Performance by an Ensemble in a Drama Series during the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

The cast of Downton Abbey, from left, Phyllis Logan, Tom Cullen, Lesley Nicol, Sophie McShera, Joanne Froggatt, Raquel Cassidy, Kevin Doyle,Tom Cullen, Allen Leech, and Jeremy Swift, hold their awards for Outstanding Performance by an Ensemble in a Drama Series during the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

The cast of Downton Abbey, from left, Phyllis Logan, Tom Cullen, Lesley Nicol, Sophie McShera, Joanne Froggatt, Raquel Cassidy, Kevin Doyle,Tom Cullen, Allen Leech, and Jeremy Swift, hold their awards for Outstanding Performance by an Ensemble in a Drama Series during the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

(L-R) Brendan Patricks, Tom Cullen, Allen Leech, Kevin Doyle, and Jeremy Swift hold their awards for Outstanding Performance by an Ensemble in a Drama Series for "Downton Abbey" during the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

(L-R) Brendan Patricks, Tom Cullen, Allen Leech, Kevin Doyle, and Jeremy Swift hold their awards for Outstanding Performance by an Ensemble in a Drama Series for "Downton Abbey" during the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

Actors Kevin Doyle (L) Allen Leech, (C) and Tom Cullen of the drama series "Downton Abbey" arrive at the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

Actor Allen Leech of the drama series "Downton Abbey" arrives at the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

Actor Allen Leech of the drama series "Downton Abbey" arrives at the 22nd Screen Actors Guild Awards in Los Angeles, California January 30, 2016. REUTERS/Mike Blake 

Actor Allen Leech arrives for the first night of Lyndsey Turner's production of Hamlet, starring Benedict Cumberbatch, at the Barbican in London, Britain August 25, 2015. REUTERS/Luke MacGregor 

Actors Rob James Collier and Allen Leech arrive for the Downton Abbey Ball at the Savoy Hotel in central London, April 30, 2015. REUTERS/Suzanne Plunkett 

Actor Allen Leech attends the 65th annual ACE Eddie Awards in Beverly Hills, California January 30, 2015. REUTERS/Phil McCarten (UNITED STATES - Tags: ENTERTAINMENT HEADSHOT) 

Allen Leech of the ITV series "Downton Abbey" accepts the award for Outstanding Performance by an Ensemble in a Drama Series at the 21st annual Screen Actors Guild Awards in Los Angeles, California January 25, 2015. REUTERS/Mario Anzuoni (UNITED STATES - Tags: ENTERTAINMENT) (SAGAWARDS-SHOW) 

Actor Allen Leech (R) and Charlie Webster attend the Producers Guild Awards in Los Angeles January 24, 2015. REUTERS/Phil McCarten (UNITED STATES - Tags: ENTERTAINMENT) 

Actor Allen Leech, from "The Imitation Game," and TV personality Charlie Webster (L) arrive at the 20th Annual Critics' Choice Movie Awards in Los Angeles, California January 15, 2015. REUTERS/Kevork Djansezian (UNITED STATES - Tags: ENTERTAINMENT) (CRITICSCHOICE-ARRIVALS) 

Actor Matthew Beard (R) poses with fellow his "The Imitation Game" cast member Allen Leech and TV personailty Charlie Webster (L) as they arrive at the 20th Annual Critics' Choice Movie Awards in Los Angeles, California January 15, 2015. REUTERS/Kevork Djansezian (UNITED STATES - Tags: ENTERTAINMENT)

Director Morten Tyldum (2nd L) poses with cast members, (from L-R), Alex Lawther, Benedict Cumberbatch, Allen Leech and Matthew Beard, from "The Imitation Game," after they won the Ensemble Performance Award backstage at the 26th Annual Palm Springs International Film Festival Awards Gala in Palm Springs, California, January 3, 2015. REUTERS/Danny Moloshok (UNITED STATES - Tags: ENTERTAINMENT) 

Actor Allen Leech poses at the 26th Annual Palm Springs International Film Festival Awards Gala in Palm Springs, California, January 3, 2015. REUTERS/Danny Moloshok (UNITED STATES - Tags: ENTERTAINMENT) 

Actor Allen Leech poses at a Los Angeles screening of "The Imitation Game" at the Directors Guild of America Theater in Los Angeles, November 10, 2014. REUTERS/Danny Moloshok (UNITED STATES - Tags: ENTERTAINMENT) 

Actors Matthew Goode (L) and Allen Leech (R) pose at a Los Angeles screening of "The Imitation Game" at the Directors Guild of America Theater in Los Angeles, November 10, 2014. REUTERS/Danny Moloshok (UNITED STATES - Tags: ENTERTAINMENT) 

Cast member Allen Leech arrives at the "The Imitation Game" gala at the Toronto International Film Festival (TIFF) in Toronto, September 9, 2014. REUTERS/Mark Blinch (CANADA - Tags: ENTERTAINMENT) 

Actor Allen Leech attends a news conference to promote the film "The Imitation Game" at the Toronto International Film Festival (TIFF) in Toronto, September 9, 2014. REUTERS/Fred Thornhill (CANADA - Tags: ENTERTAINMENT) 

Actor Allen Leech attends a news conference to promote the film "The Imitation Game" at the Toronto International Film Festival (TIFF) in Toronto, September 9, 2014. REUTERS/Fred Thornhill (CANADA - Tags: ENTERTAINMENT) 

Leeches are seen in a bottle at the clinic of doctor Tatijana Gambar in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Tatijana Gambar, a doctor, looks at a bottle containing leeches at her clinic in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Tatijana Gambar, a doctor, looks at a bottle containing leeches at her clinic in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Pino Gambar, a medical assistant, inspects leeches in bottles at the clinic of his wife and doctor Tatijana Gambar in Porec, west Croatia December 17, 2013. For the last three years, Tatijana Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Leeches, which are kept in bottles, are displayed at the clinic of doctor Tatijana Gambar in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Leeches suck blood from the neck of a patient at the clinic of doctor Tatijana Gambar in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Leeches suck blood from the neck of a patient at the clinic of doctor Tatijana Gambar in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Tatijana Gambar, a doctor, places a leech on the neck of her patient during treatment at her clinic in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Tatijana Gambar, a doctor, removes a leech from the neck of her patient during treatment at her clinic in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Tatijana Gambar, a doctor, removes a leech from the neck of her patient near Pino, her husband and medical assistant, during treatment at their clinic in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Tatijana Gambar, a doctor, provides treatment for her patient using leeches near a bottle of leeches in her clinic in Porec, west Croatia December 17, 2013. For the last three years, Gambar, who is aided by her husband Pino, provide leeching as a form of medical treatment in their clinic. The clinic receives and treats patients with various ailments such as gout, skin allergies and migraine. Picture taken December 17, 2013. REUTERS/Antonio Bronic (CROATIA - Tags: ANIMALS SOCIETY HEALTH) 

Cast members of the TV drama "Downtown Abbey" (from L:) Phyllis Logan, Michelle Dockery, Allen Leech, Amy Nuttall and Sophia McShera, hold their awards for "outstanding performance by an ensemble in a drama series backstage at the 19th annual Screen Actors Guild Awards in Los Angeles, California January 27, 2013. REUTERS/Adrees Latif (UNITED STATES - Tags: ENTERTAINMENT) (SAGAWARDS-BACKSTAGE) 

Actors Sophie McShera (L) and Allen Leech (R) attend the Entertainment Weekly Screen Actors Guild Awards nominee party in Los Angeles January 26, 2013. REUTERS/Phil McCarten (UNITED STATES - Tags: ENTERTAINMENT PROFILE) 

Aberdeen's Scott Leech (2nd R) celebrates a goal against Celtic during their Scottish Premier League soccer match at Pittodrie Stadium in Aberdeen, Scotland February 13, 2010. REUTERS/Russell Cheyne (BRITAIN - Tags: SPORT SOCCER) 

An employee of the International Medical Leech Centre demonstrates with a leech on her face in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

An employee of the International Medical Leech Centre demonstrates with leeches in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

An employee of the International Medical Leech Centre changes water in jars with leeches in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

Jars with leeches stand in the International Medical Leech Centre in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

An employee of the International Medical Leech Centre changes water in jars with leeches in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

An employee of the International Medical Leech Centre changes water in jars with leeches in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

Jars with leeches stand in the International Medical Leech Centre in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

An employee of the International Medical Leech Centre changes water in jars with leeches in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

An employee of the International Medical Leech Centre demonstrates with a leech on her face in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH SOCIETY) 

An employee of the International Medical Leech Centre demonstrates with a leech on her face in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH) 

An employee of the International Medical Leech Centre changes water in jars with leeches in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH) 

Jars with leeches stand in the International Medical Leech Centre in the village of Udelnaya, some 30 km (18.6 miles) from Moscow, December 4, 2009. The leech farm makes a tidy profit shipping them to doctors worldwide. Like many discarded elements of traditional medicine, they have made a come-back as doctors have re-discovered their pain-killing properties, which come from the chemicals they inject into the skin when they bite it. Several medical trials have proven leeches help relieve the symptoms of arthritis and other conditions. REUTERS/Denis Sinyakov (RUSSIA HEALTH) 

Ghulam Nabi Hajam, a Kashmiri paramedic, cleans blood from the face of Abdul Ahad, who suffers partial blindness, after a leech therapy session inside a hospital in Srinagar May 2, 2008. REUTERS/Fayaz Kabli (INDIAN-ADMINISTERED KASHMIR) 

Leeches suck blood from the leg of a woman patient during a leech therapy session inside a hospital in Srinagar May 2, 2008. REUTERS/Fayaz Kabli (INDIAN-ADMINISTERED KASHMIR)