CDC researcher Timothy Cunningham has not been since since going home sick two weeks ago

Dr Timothy Cunningham left his dog at home on the day he disappeared. Photo / Supplied

Timothy J. Cunningham had been a rising official at the Centres for Disease Control and Prevention.

The Harvard-educated epidemiologist was promoted in July at the US Public Health Service in Atlanta and contributed to responses to outbreaks of Zika, Ebola and health emergencies caused by Hurricane Sandy. He also was a prominent fixture in the Atlanta community, earning a spot in Atlanta Business Chronicle's 40 Under 40 Awards last year.

But the researcher, who studies disease patterns, was not feeling well on February 12 and left work around midday.

Cunningham, 35, hasn't been seen or heard from since, his family and police have said, sparking a $10,000 reward offered by the family in partnership with Crime Stoppers Greater Atlanta for information leading to an arrest and indictment for his disappearance.

"I feel like I'm in a horrible

Black Mirror

episode," his sister, Tiara Cunningham, told the

New York Times

, referencing the dystopian sci-fi television show. "I'm kind of lost without him, to be quite honest."

She told the paper she speaks with her brother often, but their conversation on February 12 worried her. "He sounded not like himself," she said. He did not reply to a text message she sent later, and their mother, Tia-Juana Cunningham, did not reach him either.

She and Cunningham's father, Terrell Cunningham, drove all night from their home in Waldorf, Maryland, to Atlanta, about 1000km away, arriving on Valentine's Day. What they discovered in their son's home raised more questions. Left behind were Cunningham's unattended dog, Mr Bojangles, and his wallet, cellphone and driver's license. His car was in the garage, the Times reported.

Terrell Cunningham also had concerns about recent interactions with his son, whom he described as focused on a host of professional and personal issues.

"The tone and the numerous exchanges gave us reason to be concerned about Tim," he said. "And I don't know if it's an instinct you have because it's your child, but it was not a normal conversation, and I was not comfortable."

The family did not immediately respond to a Washington Post request for comment.

The Atlanta Police Department said on Sunday it was still unable to find Cunningham after learning on February 16 about his disappearance and that it was depending on public awareness to help draw leads. Foul play is not suspected at this time, police spokesman Donald T. Hannah said.

The Centres for Disease Control described Cunningham as a "highly respected member of our CDC family", ABC News reported. CDC officials did not reply to a request for comment.

In his 40 Under 40 profile last year, Cunningham said he was "using the skills I have to improve and help the lives of others", referring to his work at the CDC.

The publication said he was continuing on his family's path into medical care; his father was an Air Force nurse for 30 years, and his mother worked for the state health department as a programme manager.

Leonte Benton, a friend who met Cunningham in a professional development group, said Cunningham "consistently made an impact on the local community and throughout the world".

The Cunningham family, meanwhile, continues their own dogged search as they sort out the bewildering disappearance.

"We just hope he will just come home safely. None of this makes sense. He wouldn't just evaporate like this and leave his dog alone and have our mother wondering and worrying like this. He wouldn't," Cunningham's brother, Anterio, told Fox 5 in Atlanta.