DOWNEY, Calif. — A high school wrestler died from complications of a drug-resistant staph infection and a teammate was being treated for the illness.

Noah Armendariz, 17, died Sunday at Children's Hospital of Orange County from methicillin-resistant Staphylococcus aureus, or MRSA.

"The medication was doing its job but the infection was too aggressive," said his grandfather, Frank Magana.

Armendariz, of Downey, developed a rash and flu-like symptoms after returning from a high school wrestling camp in Lake Arrowhead last month, said his mother, Cynthia Magana.

He became progressively sicker, contracted pneumonia and had holes in his lungs, she said.

A teammate who did not attend the camp tested positive for staph a week after Armendariz became ill but his condition is not serious, Downey High School wrestling coach Miguel Soto said Wednesday.

Four other wrestlers got rashes but tested negative for staph, he said.

MRSA is resistant to some antibiotics but can be treated with other medications. It mainly causes skin infections but can prove deadly. An estimated 90,000 people in the United States fall ill each year from MRSA. In 2005, about 18,650 died from MRSA infections, according to a study last year by the Centers for Disease Control and Prevention.

Outbreaks have been reported in jails, schools, gyms and on sports teams.