Masters, 63, died Sunday at Southeast Missouri Hospital in Cape Girardeau.
"It's a loss to the world," said Paul Walters of Alton, Ill., a former patient of Masters making the three-hour drive for today's visitation. "He was an amazing person."
Rusty Newton of Advance, Masters' sister, described Masters as "a renowned and beloved family physician."
"He loved being a doctor," she said. "Solving complicated medical cases was the challenge he relished most."
One of the biggest challenges Masters faced was the one he is best remembered for.
"He spent the better part of his medical career researching, documenting and treating tick-borne diseases and was internationally known for his work with Lyme disease," Newton said.
Due to his extensive research on Lyme-like diseases and a critical discovery, STARI (Southern tick-associated rash illness) is also known today as Masters disease.
"It should be called Masters disease," said Walters, who is among the many treated by Masters for Lyme-like diseases. "Ed Masters is the one who isolated it."
Doctors from all over the country would refer their patients to Masters advising he was "the one man who could help them," Newton said. "People would call to try to get an appointment to see him and couldn't get in."
Some managed to track Newton down at her former home in Kansas City and plead with her to ask her brother to schedule an appointment for them. "And he did on many, many occasions," she said.
Newton recalled how when some patients were too weak to make the drive down here, Masters would drive to meet them at the airport.
"The first time I came to see the man I was just amazed -- I saw license plates from all over the United States in the parking lot," Walters said.
"I had been off work for years trying to find a solution to my illness," he recalled.
And when Walters' health insurance wasn't accepted, "he refused to take my money," Walters said. "He was probably the most decent person I met in my entire life."
Newton noted that Masters also made lasting impressions at another level as a mentor for many promising young students who aspired to be physicians.
Among these is Chelsea Grigery who is now in her fifth year of a six-year bachelor's degree/medical school program at University of Kansas City.
"I credit my acceptance into this program to Dr. Masters," Grigery said. "It is because of him that I am where I am today. I credit my interest in medicine and research to Masters because he opened up so many avenues for me and provided me with so much experience and support."
Grigery worked with Masters on Lyme disease research projects as both a junior and a senior at Sikeston High School in 2004 and 2005.
In the second project, "Dr. Ed was extremely influential in helping that to be a successful experiment," she said. "He used his contacts in the Lyme disease circle of researchers to connect me with the people to help me with this project."
Masters then helped Grigery get the work published in Missouri Medicine.
"I was the youngest author to ever be published in that journal - that is totally thanks to him, Grigery said. "He was by far the most influential person in my young adult life -- a phenomenal physician, educator, researcher. I view him as a father figure -- I was that close to him. Both he and his wife, Miss Jackie, invited me into their home for hours on end to work on these programs and never made me feel unwelcome. Miss Jackie is just a phenomenal woman, an excellent wife and mother and friend. They treated me as one of their own children. He used to joke that I was his fifth child."
"Dr. Masters was most proud of his family. He delighted in their achievements and successes and was lovingly called "Papa Doc" by his grandchildren," Newton said. "He believed that his illness had a very positive gift and that was having more time with his family."
"He always tried to make sunshine out of the rain," Walters agreed.
"Dr. Masters will be remembered not only for his list of achievements but also for his brilliant intellect, wisdom, integrity, optimistic spirit, perseverance in the face of great obstacles, humanity, love of his family and his unique, contagious laugh," Newton said. "He was my hero."