SAN DIEGO -- Authorities released the name Wednesday of the first person to die from swine flu-related complications in the San Diego area.

Adela Chevalier, 20, succumbed to the illness in an emergency room at Palomar Medical Center in Escondido on Monday afternoon, two days after she began feeling sick, according to the county Medical Examiner's Office.

Chevalier, who lived in a San Marcos apartment with her brother, apparently had been healthy prior to contracting the virus and had not traveled recently, officials said.

Her death was the seventh swine flu-related fatality in California, according to the San Diego County Health and Human Services Agency.

10News learned from family members that Chevalier worked at a Kentucky Fried Chicken restaurant on Nordahl Road in San Marcos.

KFC representative Laurie Schalow issued the following statement:

"Our condolences go out to our employee’s family, friends and everyone mourning her loss. She will be missed by all who worked with her and knew her. While the H1N1 virus is not spread by eating or handling food, as a precautionary measure our restaurant has been thoroughly cleaned and sanitized and all employees are being tested for the H1N1 virus."

Additionally, Chevalier worked at the Mountain Shadows Care Center on El Norte Parkway in Escondido but her last day there was June 6, 2009, relatives told 10News.

The center is an assisted living facility for people with disabilities, and there are 200 employees and about 100 residents at the center.

The center's executive director told 10News' Juliette Vara that Chevalier was a part-time employee, but he did not know how long she had been employed.

No one has shown any symptoms of the H1N1 virus, but as a precaution staff members will be checking residents every day at 6 a.m. and 6 p.m. for flu-like symptoms, according to the executive director.

Chevalier's 23-year-old brother, Joel Rivera, lived with her and was taken to Palomar Hospital on Tuesday after a hospital spokesman said Rivera tested positive for the flu.

Rivera is in a private, isolated room to keep him from infecting anyone else, the spokesman said.

Hospital officials said they were waiting for county health officials to confirm whether or not Rivera has the swine flu.

Rivera told 10News' Joe Little that doctors have told him he has the H1N1 virus. He said he doesn't know when he will be released.

Rivera said he is still in shock over the loss of his sister. He told Little that he began coughing a little bit earlier this week and did not think anything of it.

Rivera said Chevalier did not think she was seriously ill when she began displaying symptoms.

He said his friends became even more concerned for him after his sister died.

"I didn't notice I was sick. My friends we're just bugging me about me going to the hospital Tuesday night. They brought me here and left me here," said Rivera.

When Rivera is released he said he will have to remain quarantined in his apartment for at least seven days.

10News learned that Rivera was employed at the Pizza Hut located on 705 Center Drive in San Marcos.

Pizza Hut representative Christopher Fuller issued the following statement:

"Like everyone else in the community, we are concerned about the situation and are monitoring it very closely. We've communicated with all employees about the seriousness of this flu and the procedures they should take if they display any flu-like symptoms."

County Public Health Officer Wilma Wooten called the young woman's lethal illness "a tragic reminder that the H1N1 virus is still very much active in our community."

"Residents of San Diego County still need to be vigilant about H1N1 and take the necessary precautions of covering their mouth when they cough, sneeze or blow their nose, and wash their hands frequently," Wooten said.

"We are still monitoring this virus and working with local, state and national health officials, but it will be several months before a vaccine is developed for H1N1."

There have been 275 confirmed cases of the disease in the San Diego region. Twenty-five of them have necessitated hospitalization.

People who had been in close contact with Chevalier recently have received post-exposure treatment, authorities said.