The latest U.S. doctor to contract Ebola in Africa was working with outpatients in 100-degree temperatures that made it difficult to wear protective gear when he was exposed to an obstetrics patient stricken with the deadly disease, said another American physician who worked in the same hospital.

Dr. Rick Sacra, a 51-year-old physician from Massachusetts, was working in the obstetrics unit of the massive Elwa Hospital in the Liberian capital of Monrovia, far from the Ebola unit, said Dr. Jeff Deal, a South Carolina doctor who traveled to Liberia to help battle the crisis engulfing much of Africa. Doctors and other health care workers often do not wear protective gear in the general part of the hospital, most of which has no air conditioning. With high temperatures compounded by equatorial humidity, many doctors and healthcare workers outside of the Ebola unit skip protective gear.

"I was pretty shocked when I heard," Deal said. "At first I thought should I isolate myself, but now I have been a little comforted that I have been wearing protective clothing at all times, and no one who has followed the proper protocols has fallen sick.”

Although the hospital's Ebola Treatment Unit is sanitized constantly, including through the use of an ultraviolet ray-emitting machine Deal arranged for, outpatients who see workers in other parts of the facility, who have not been diagnosed and may be in denial about their symptoms— often come in contact with unprotected staff, Deal said.

Nurses at the hospital went on strike Monday, in part for better pay due to hazardous conditions, but also for access to more complete protective gear.

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In the latest case, Sacra was treating a patient for an obstetric condition and told staff the woman was "highly suspicious" and displaying Ebola symptoms.

Doctors Without Borders, the medical charity that runs the Ebola unit, use three-layered, disposable uniforms that include a hood, boots, apron, bib, gloves and goggles. Deal said working in the suits is exhausting, and doctors can last little more than 3-4 hours in them. Deal said it takes more than 30 minutes to get out of the suit, and a bleach solution must be applied on each newly-exposed layer.

Sacra, who is a missionary with SIM USA, a faith-based charity headquartered in Charlotte, N.C., isolated himself in the hospital's Ebola unit immediately after experiencing symptoms and is doing well, according to officials with SIM, which originally stood for Sudan Interior Mission when it was founded in 1893.

"My heart was deeply saddened, but my faith was not shaken, when I learned another of our missionary doctors contracted Ebola," said Bruce Johnson, president of SIM USA. "As a global mission, we are surrounding our missionary with prayer, as well as our Liberian SIM/ELWA colleagues, who continue fighting the Ebola epidemic in Liberia. We have gifted Liberian doctors, medical staff and support staff who are carrying on the fight."

Deal said Sacra will be treated with a balance of electrolytes and intravenous nutrition and likely has the same survival outlook as those who have been brought back to the U.S. for treatment. He said the high mortality rate for Africans is likely due to delays in getting treatment and the fact that patients may have other diseases, including malaria or dengue fever.

Deal said Sacra will likely be brought back to the U.S. in the event his condition worsens.