A prisoner from the Pedrinhas prison is carried to receive medical help after he was injured during a fight between rival gangs inside the jail, in Sao Luiz, capital of Maranhao state, January 8, 2014. The recent posting on a major Brazilian news website of a video filmed last December 17 by Pedrinhas prisoners of the decapitated and tortured bodies of rival inmates inside the jail has highlighted some of the problems present in the country's prison system which houses nearly twice as many prisoners as its capacity, according to official statistics. (Photo by Douglas Cunha/Reuters/O Estado do Maranhão)

Coloured X-ray of a barn owl. A physicist has used X-ray to create an extraordinary collection of artwork. Arie van't Riets pictures reveal birds, fish, monkeys and flowers in an incredible new light. The 66-year-old, from Bathmen in the Netherlands, began X-raying flowers as a means to teach radiographers and physicians how the machine worked. But after adding a bit of colour to the pictures, the retired medical physicist realised the potential for an exciting new collection of art. (Photo by Arie van't Riet/Barcroft Media)

Medical residents, who removed their clothes to protest against working conditions, take part on a protest during a strike in Barcelona, Spain, Tuesday, October 20, 2020. Regional authorities across Spain continue to tighten restrictions against a sharp resurgence of coronavirus infections that is bringing the country’s cumulative caseload close to one million infections, the highest tally in western Europe. (Photo by Emilio Morenatti/AP Photo)

Medical staff in Belgrade, Serbia on February 5, 2021. Vaccination of employees in the city's social protection institutions has begun at the Belgrade Fair, who have expressed interest in receiving the Russian Sputnik V vaccine, and according to the city secretary for social protection Natasa Stanisavljevic, about 150 employees in those institutions will receive the vaccine today and tomorrow. (Photo by Zoran Zestic/Tanjug)

A medical worker wearing a full protective outfit tests a man for Covid-19 symptoms in a street in Wuhan, China, 01 April 2020. Wuhan, the epicenter of the coronavirus outbreak, partly lifted the lockdown allowing people to enter the city after more than two months. According to Chinese government figures over 2,500 people have died of Covid-19 in Wuhan since the outbreak began. (Photo by Roman Pilipey/EPA/EFE)

A grasshopper in a protective mask created by microminiaturist Anatoly Konenko in Omsk, Russia on May 21, 2020. Mini-masks about the size of a rice grain are made of a special high-density medical fabric with a built-in air filter. Anatoly Konenko is one of Russia's most famous microminiaturists; his works include a grasshopper playing a violin, a shod flea, a miniature bass guitar, a camel train in a needle's eye, and over 200 miniature books. (Photo by Yevgeny Sofiychuk/TASS)

An amazing artist transforms scrap metal into incredible sculptures of insects, birds, fish, and other animals. Edouard Martinet from Brittany, France, creates the sculptures from all manner of salvaged parts and junk, including car and bicycle parts, typewriters, and medical equipment. Photo: An ant by Edouard Martinet. (Photo by Edouard Martiniet/Caters News)

A girl who suffers from hearing and speech disorders reacts to the camera at a rehabilitation centre supported by Bhopal Medical Appeal, for children who were born with mental and physical disabilities, in Bhopal November 11, 2014. The rehabilitation centre only treats families they believe have been affected by the Union Carbide gas leak 30 years ago. Human rights groups say that thousands of tonnes of hazardous waste remain buried underground, and the government has conceded it is contaminated. There has, however, been no long-term epidemiological research which conclusively proves that birth defects are directly related to the drinking of the contaminated water. (Photo by Danish Siddiqui/Reuters)