Deputies said the victim's personal belongings were also in the cage.
The woman was locked in the cage at night to prevent her from wandering off, police said.
Spokeswoman Dawn Panepinto told The Advocated in a Thursday news release investigators "discovered that the accused conspired to transport the young woman to a specific location with the intention of prostituting her out to multiple male subjects for money." She was malnourished and had numerous insect bites, Panepinto said.
Tangipahoa Parish Sheriff Daniel Edwards told WBRZ the woman may have been living in those conditions since October 2015.
The woman and four juveniles were taken from the home and are in the custody of the Louisiana Department of Health's Adult Protective Services and the Louisiana Department of Child and Family Services.
Raylaine Knope, 40, Bridget Lambert, 19, Taylor Knope, 18, Jody Lambert, 21, and Terry Knope, 43, have been arrested and charged with human trafficking and cruelty to the infirmed.
Panepinto said the investigation is ongoing and more charges may be to come.
#BREAKING: Five people in Tangipahoa Parish are facing human trafficking and cruelty charges after a malnourished 22-year-old autistic woman was found living in a cage in the backyard.Posted by WGNO-TV | ABC26 on Thursday, July 7, 2016