Two boys look out from the Mangueira slum towards the Maracana Stadium that is hosting the Rio's 2016 Summer Olympics opening ceremonies, in Rio de Janeiro, Brazil, Friday, August 5, 2016. (Photo by Leo Correa/AP Photo)

A sofa floats in the polluted waters of Jacarepagua Lagoon, during a press tour in Rio de Janeiro, March 9, 2015. A press tour was organised by biologist Mario Moscatelli, to call attention to pollution on the waters of the lagoons which surround the Rio 2016 Olympic Park. (Photo by Ricardo Moraes/Reuters)

Children play in an outdoor shower as a soldier takes part in a surprise operation in the Manguinhos slum in Rio de Janeiro, Brazil, Thursday, January 18, 2018. Troops have been sent to Rio due to the increase of the violence, and in an attempt to help restore order, but so far have had little impact. The operation on Thursday took place three weeks ahead of Carnival, when thousands of tourists are expected to arrive in the city. (Photo by Leo Correa/AP Photo)

Men look on from the banks of Rio Doce (Doce River), which was flooded with mud after a dam owned by Vale SA and BHP Billiton Ltd burst, as the river joins the sea on the coast of Espirito Santo in Regencia Village, Brazil, November 22, 2015. (Photo by Ricardo Moraes/Reuters)

In this November 17, 2014 photo, Pancho, a domesticated huitia, confronts a camera, in Bainoa, Cuba. With their rope-like, dark tails, long front teeth, and whiskers that appear to be vibrating, huitias look like giant rats. They measure nearly a foot long (about 30 centimeters), with the largest ones weighing in bigger than a small dog. (Photo by Ramon Espinosa/AP Photo)

A newly married bride is seen after a mass wedding ceremony in which 2,016 couples participated, at Zocalo square in Mexico City, Mexico, March 19, 2016. Thousands of couples took part in a mass wedding ceremony Saturday in Mexico City. More than 5,000 people descended on Mexico City’s central square for the festivities. Among them were 2,165 couples ready to get married. (Photo by Edgard Garrido/Reuters)

An Indian bride, sits during a mass marriage of 162 Muslim couples in Ahmadabad, India, Sunday, March 3, 2013. Mass marriages in India are organized by social organizations primarily to help the economically backward families who cannot afford the high ceremony costs as well as the customary dowry and expensive gifts that are still prevalent in many communities. (Photo by Ajit Solanki/AP Photo/LaPresse)

Performer from the Mangueira samba school parades during carnival celebrations at the Sambadrome in Rio de Janeiro, Brazil, Tuesday, February 9, 2016. (Photo by Silvia Izquierdo/AP Photo)