BRASILIA, Brazil (AP) — Each week, patients at the Support Hospital of Brasilia receive visits from a special breed of therapist: dogs trained to help them recover from disease or injury.

In this Nov. 24, 2016 photo, Nivaldo Lopes, a 60-year-old geriatric patient, pets a Schnauzer dog named Paola on his bed at the Support Hospital of Brasilia, Brazil. The hospital's pet therapy project began this year and now counts dozens of volunteers who bring their pets to the hospital in Brazil's capital each week. At right is Shitzu therapy dog named Mille, its owner and a doctor. (AP Photo/Eraldo Peres)

Big and small, from German shepherds to Shih Tzus, the dogs get into bed with some patients to snuggle during the 15-minute visits. Folks who are more mobile may take an animal to a crafts class, or play with it in the hallways.

In this Nov. 17, 2016 photo, Priscila Cremer walks a German shepherd named Pacato to visit another patient as they make their rounds as part of a pet therapy program every Thursday at the Support Hospital of Brasilia, Brazil. In addition to receiving training, animals who are part of the hospital's pet therapy program have undergone extensive health checks, including vaccinations and deworming. (AP Photo/Eraldo Peres)

Designed for people who have advanced-stage cancer, live with chronic disease or are recovering from trauma, the program of canine interactions assists with both mental and physical rehabilitation.

In this Nov. 17, 2016 photo, 20-year-old patient Gleisiane Oliveira watches Shitzu dog named Mille be given a treat on her bed at the Support Hospital of Brasilia, Brazil. The animals are the "stars of the project," according to Nayara Brea who coordinates a pet therapy program for patients with advanced cancer, those living with chronic diseases and recovering from trauma. (AP Photo/Eraldo Peres)

"A bit of the sadness goes away," said Jaqueline Castro, a 27-year-old patient with a degenerative nerve disorder who received three visits in a month.

In this Nov. 17, 2016 photo, Antonio Araujo, a 67-year-old geriatric patient, gets a visit from a Shitzu dog named Mille as he rests in bed at the Support Hospital of Brasilia, Brazil. Therapy dogs, big and small, from Shih Tzus to German shepherds, spent 15 minutes with patients every Thursday as part of a pet therapy program. (AP Photo/Eraldo Peres)

The project began about five months ago and now counts 60 volunteers who bring their pets to the hospital in Brazil's capital each week.

In this Nov. 17, 2016 photo, a Schnauzer dog named Paola lays with Jaqueline Castro, who is being treated for a degenerative disease, in her bed during a 15-minute visit at the Support Hospital of Brasilia, Brazil. Patients who are more mobile can bring the pet therapy animals to classes or play with it in the hallways. (AP Photo/Eraldo Peres)

But not just any old mutt can make the cut: Only about one out of every 10 dogs whose owners volunteer is accepted, according to program coordinator Nayara Brea.

In this Nov. 17, 2016 photo, Soraya Avila shows off her dog Raja running through an obstacle course set up in the hallway of the Support Hospital of Brasilia, Brazil. In addition to receiving training, animals who are part of the hospital's pet therapy program have undergone extensive health checks, including vaccinations and deworming. (AP Photo/Eraldo Peres)

The animals must pass extensive health checks and undergo training, as they are brought right into the wards of the hospital. They must be exceptionally calm to avoid stressing out the patients. They can't bark, and they have to be gentle with both humans and other canines.

In this Nov. 17, 2016 photo, Euripedes Carreira, a 67-year-old being treated for cancer, interacts with a Shitzu dog named Mille and German Shepherd named Pacato, as part of a pet therapy program at the Support Hospital of Brasilia, Brazil. Every Thursday, patients here receive visits from a special breed of therapists: dogs trained to help them in their recovery from disease or injury. (AP Photo/Eraldo Peres)

A therapy dog "accepts the patients without any judgment," said Valeria Carvalho, who brings her miniature Schnauzer, Paola, to the hospital. "People start to have a different perspective on life, on health."

In this Nov. 17, 2016 photo, volunteers lead their therapy dogs into the Support Hospital of Brasilia to visit patients in Brasilia, Brazil. The hospital's pet therapy project began about five months ago and now counts 60 volunteers. (AP Photo/Eraldo Peres)