Brewer native Sheila Davis is in West Africa, at the heart of the Ebola outbreak. She is surrounded by a deadly virus that has instilled fear in many Americans who will never come face to face with its devastation, and wants the public to know Ebola can be stopped — with science, not hysteria.

Davis, 49, a nurse practitioner who graduated from Brewer High School in 1983, traveled to Liberia in early October to lead the Ebola response for Partners In Health, a Boston-based international aid organization focusing its relief efforts in the rural countrysides of the region.

“The panic in the media and misinformation is unfortunate and is hurting rather than helping this epidemic,” Davis wrote in an email from Liberia. “This epidemic CAN be stopped if we let the science and epidemiology drive our strategy and stop this in West Africa.”

The Ebola outbreak — the worst in recorded history — has claimed the lives of more than 4,500 people at its epicenter in Liberia, Sierra Leone and Guinea. Many patients lack adequate treatment, and some children have lost both parents and extended family. The stigma and fears about Ebola complicate efforts to return children to their villages, Davis said.

Sadly, the challenge of children orphaned by disease is familiar to Davis, who previously worked in countries devastated by HIV and AIDS.

Ebola’s death grip on West Africa has advanced beyond those stricken with the disease, preventing hospitals from treating day-to-day illnesses and injuries, she said. Some are overwhelmed with Ebola patients, while other clinics have closed because of panic or because the virus has sickened medical staff.

“Routine medical problems are not able to be treated because most of the hospitals are closed to Ebola — people are dying from treatable illness such as malaria, motor vehicle accidents, treatable diarrheal infections and women in childbirth,” Davis wrote. “This is a tragedy that extends far beyond Ebola.”

Food prices have spiked rapidly, and concerns grow serious about potential security issues as governments crumble under the weight of the epidemic, she said. The World Bank has projected the cost of the outbreak could hit $32 billion by the end of 2015 if it spreads to neighboring countries.

But there are signs of hope.

While many U.S. headlines have focused on missteps by a Texas hospital, where two nurses became infected after treating an Ebola patient, thousands of health care workers in West Africa have avoided infection while working in far less ideal circumstances, Davis said. Her team trained with the U.S. Centers for Disease Control and Prevention in Atlanta before leaving for Liberia. She said the risk of infection is greatly reduced with the correct personal protective gear, including impermeable suits, hoods, masks, boots, goggles and gloves; and strict protocols for patient care and donning and removing the equipment.

“There is fear here but also a strong sense of commitment and urgency to help in this tragic epidemic,” Davis wrote. “The health system in the U.S. is very strong — there are problems of course — but if Ebola entered the U.S. in a large way, we have a way to stop and to treat it.”

Health officials continue to stress that the risk of an outbreak in the U.S. is very low.

Another African country, Nigeria, was officially declared free of Ebola on Monday, months after an infected air traveler introduced the virus to Lagos, its most populous city.

Ebola patients can survive with treatment by trained health care workers equipped with the right supplies and system to support them, she said. A co-founder of her organization, Dr. Paul Farmer, blamed weak health care systems for the outbreak’s high rates of death in an essay published last week by the London Review of Books.

“An Ebola diagnosis need not be a death sentence,” Farmer wrote. “Here’s my assertion as an infectious disease specialist: if patients are promptly diagnosed and receive aggressive supportive care — including fluid resuscitation, electrolyte replacement and blood products — the great majority, as many as 90 percent, should survive.”

Partners In Health aims to treat Ebola cases and collaborate with local groups to contain the disease’s spread. It is working alongside Last Mile Health in Liberia and Wellbody Alliance in Sierra Leone, two grass-roots organizations.

The Boston organization plans to open its first Ebola treatment unit in Liberia in a few weeks, with 50 beds, said Davis, who serves as its chief nursing officer. The nonprofit — also collaborating with local governments, ministries of health, the United Nations and the World Health Organization — hopes to open at least three of the units in Liberia and 15 or more in Sierra Leone, where Davis is now headed. Their efforts also include educating people in rural areas about the disease and strengthening the overall health system, Davis said.

“It is a challenging time for both countries,” she wrote. “There is a lot of fear but the leaders and people of Liberia are working very hard to combat this epidemic.”

If the U.S. chooses to institute travel restrictions, the critical work of mobilizing health care workers and resources from around the globe will only suffer, Davis said.

“The best way to prevent Ebola from entering the U.S. in a widespread way is to treat it IN West Africa where the epidemic is. … (If) the U.S. closes its borders and prevents people from going over to help and get home safely, then we will end up with a huge global epidemic which will be impossible to stop,” she wrote.

Calls for travel restrictions have grown louder in the U.S. in recent days. U.S. House Republicans are demanding President Barack Obama impose new travel restrictions from countries ravaged by the virus to protect Americans from the outbreak. Obama has said “a flat-out travel ban is not the way to go,” while U.S. CDC Director Tom Frieden told lawmakers a ban could worsen the crisis by making potentially infected travelers determined to enter the U.S. harder to trace.

Nearly half of Americans say they’re avoiding international air travel because of the Ebola outbreak, a Reuters/Ipsos poll found.

After spending a few weeks in Sierra Leone, Davis plans to fly back to her home in Boston for a short time before returning to Africa to continue battling the outbreak.

Her father, Bill Davis of Brewer, says he’s proud of his daughter but is constantly worried about her. He shares updates about her work in West Africa on his Facebook page, asking friends for “prayers and positive vibes.”

In her emails to him, she describes walking through bleach baths and having her temperature taken everywhere she goes, and she shares her concerns about the dire need for more nurses and physicians. Partners In Health has taken responsibility for an area in the southeast of Liberia largely inaccessible by car or truck, home to a mining camp where supplies and staff must be flown in by helicopter, she wrote in an email to her father, a professor emeritus of education at the University of Maine.

“We decided early on to laugh rather than cry,” she wrote to her father. “So our approach to stress relief is thus far working, but I fear we are all exhausted at this point, and it will not be possible to maintain this pace.”

A sense of responsibility continues to drive her work, one she believes all of society shares.

“We have a moral imperative to help each other as human beings regardless of where we were born and where we live,” Davis wrote. “We live in a global community — we cannot ignore what is happening across the ocean.”