Chellie was in a hurry. A missionary was waiting for her at the wilderness lodge in Sossusvlei. Chellie was on her way to photograph children orphaned by AIDS. As she has so many times in the last three years, Chellie had left her home in Lake Oswego to gather African children on her knees, let them play with her hair and listen to their stories.

Chellie had been warned about traveling alone, but she needed pictures from Namibia for the last chapter of her book, whose profits will go to African AIDS orphans.

In Africa, 16 million children are without parents, Chellie says. "They smile all the time, even though some have watched their mothers and fathers die, the 47-year-old woman says. "And even if they're only 7 years old, they take responsibility for their siblings. There are towns in Zimbabwe where there are no adults left. And yet these beautiful children still have some kind of joy and hope."

According to UNAIDS, an umbrella organization that includes five United Nation agencies, including the World Health Organization, and the World Bank, 24.5 million people in sub-Saharan Africa have AIDS. UNAIDS says another 19 million already have died from the disease, leaving a generation of orphans, many of whom are infected themselves, many who've been abandoned by their extended families. The U.S. Agency for International Development says the number of orphans will grow to 28 million by 2010. Other experts say African orphans could number 40 million by then.

African orphanages can't begin to care for the huge numbers of children who are malnourished and rarely attend school.

Chellie learned of the orphans when her husband was transferred by his high-tech computer firm to South Africa five years ago. AIDS orphans in institutions and on the streets touched Chellie's heart. She organized fund-raisers and bought toys for the children. But it never felt like enough.

So after she and her family returned to Oregon three years ago, and her own children left for college, Chellie created a nonprofit organization called The "Q" Fund, and began making photographic expeditions to AIDS hot spots in Africa. Chellie plans to publish a book filled with the faces and stories of AIDS orphans. Later, Chellie says, she hopes to do books on AIDS orphans on other continents.

"I'm a good photographer. My aunt was a photographer for National Geographic, and I've had a camera in my hands since I was 6 years old." She also spent a few years in front of cameras in the 1970s, as a model in New York City. "I just felt compelled to use my skill to raise awareness and raise money for these children."

On March 14, Chellie had driven her rented Toyota truck for hours, racing to meet the missionary who was to be her guide, before she realized the gas gauge was stuck. "I got out a map and found a small symbol of a gas pump. So I pulled off the beaten path of the gravel road." Chellie drove a long way on a sand road and finally found the one-tank gas station.

After filling up, she headed back the way she'd come. "Suddenly in front of me is a herd of impala. . . . I swerved out of the way and hit a tremendous boulder headfirst." The truck flipped, Chellie's head smashed into the window, and the Toyota came to rest on the passenger side. "I woke up in complete darkness, still strapped into my seat belt. My head hurt badly, and the smell of gasoline was nauseating. I had gas all over my clothing."

Chellie freed herself from the seat belt. The passenger window beneath her had broken, leaving "shattered pieces of glass like sharp snowflakes under me. I put my suitcase over the open hole to block it. Snakes are so abundant in the desert."

The message on Chellie's rented cell phone told her, in a clipped British accent, "You are presently out of network range." "In that moment I almost surrendered to fear."

All night she watched the bowl of stars above and struggled, through a bad concussion, to focus her thoughts. "I'm in the middle of the desert where no one is ever, ever going to find me, because I've left the main road. It could have been weeks before someone came by. I couldn't find my water. And I knew the next day could go up to 120 degrees. I would have died in the truck. I knew I had to walk out."

It was 13 kilometers --more than 8 miles -- back to the gas station. Sossusvlei was a three-day walk in the other direction. She was in leopard country. "In Namibia leopards are as common as stray cats in Rome. They are everywhere." In the dark, Chellie licked the blood from her wounds from the broken glass. At dawn, she buried her urine. "Both are tart, delicious scents to the predator."

In the early light she saw leopard tracks around the truck. Fighting her fear, she set off with three figs, a bottle of herbal Rescue Remedy and her passport, "so if a leopard got me, at least my family would know what happened to me."

Chellie never saw a leopard, but she was followed by a large baboon for three hours. She also heard the calls of warning birds that scream when the cats are near. She believes the reek of gasoline kept her from being attacked.

Her head hurt fiercely. Her lips and tongue swelled, but she kept walking. "I thought about my children, the orphans, my life and what I've given up to do this book. I was afraid I might die. I had flashes of memories . . . as if it was a walk through my life."

Chellie walked nearly five hours before a hunter spotted her and took her to his home, where he called for help. She was transported to a hospital in Windhoek, the Namibian capital.

A day later she was released. Her brush with death, she knew, was nothing compared to the challenges and tragedies African orphans face. She flew home to Oregon, more determined than ever to continue her work.

"Photographs are very powerful," she says. "And because I know these children are out there, it's almost my duty to take care of them."

People ask Chellie all the time why she does this. She admits she has asked that question herself. "I realize for the last two years I've taken unbelievable risks with my life. I could easily be killed or contract malaria or who else knows what. My family is proud of me, but I also think they wonder where I've gone. And I think they worry. I have great kids, a great job, a great life. . . . But I'm compelled to do this. I feel almost like a lightning bolt came out of the sky and hit me. When you're tagged, you're it. You can't ask why."