CDC says American tests positive for Ebola in Africa, risk in the U.S. remains low

One American has tested positive for Ebola in the Democratic Republic of Congo in connection to the deadly outbreak in central Africa that global health agencies are racing to contain, the Centers for Disease Control and Prevention said on Monday.

The person was exposed as part of their work in Congo, developed symptoms over the weekend and tested positive late Sunday, Dr. Satish Pillai, the CDC's Ebola response incident manager, told reporters on a call. The CDC and State Department are working to move that individual and six other Americans exposed to Ebola to Germany for treatment, care and monitoring. 

But Pillai emphasized that no cases tied to the outbreak have been confirmed in the U.S., and that the overall risk to the American public and travelers remains low.

Still, the CDC also announced on Monday that for the next 30 days, it will restrict entry into the country for people without a U.S. passport who were in the Democratic Republic of the Congo, South Sudan or Uganda in the last three weeks.

The update came one day after the World Health Organization declared the Ebola epidemic a "public health emergency of international concern." The outbreak does not meet the criteria of a "pandemic emergency," but the WHO warned that the high positivity rate and increasing cases and deaths point toward a "potentially much larger outbreak" than what is being detected and reported.  

As of Sunday, more than 300 suspected cases and 88 suspected deaths have been reported, primarily in Congo but also in neighboring Uganda, according to the CDC.

The specific virus involved in this outbreak, called Bundibugyo, has no vaccine or treatment. Historically, that virus has death rates ranging from 25% to 50%, the CDC added. 

The symptoms of Ebola disease can be sudden and include fever, fatigue, muscle pain, headache and sore throat, according to the WHO. Those flu-like symptoms can be followed by vomiting, diarrhea, abdominal pain, rash and impaired kidney and liver functions.

"One concern, specifically with this outbreak, is that this Ebola strain is one that's not very common and really hasn't been seen recently, and we really don't know if the current Ebola vaccine is going to be effective to prevent disease, prevent infection," Dr. Dean Blumberg, chief of the division of pediatric infectious diseases at UC Davis Health, said in an interview.

CDC officials told reporters on Monday that work is underway to develop a monoclonal antibody therapy as a potential treatment for this specific strain of Ebola. But it's unclear how long that process would take.

Blumberg said cases in the U.S. may appear, but emphasized that the outbreak is unlikely to escalate to a Covid-style pandemic.

That's because there is "no person-to-person transmission in the pre-symptomatic phase, so there is no risk for someone who is appearing well," he said. Patients who have Ebola are going to be "very sick" and won't be out in public to expose others, so there should be "limited transmission."

The global awareness of this outbreak should also prompt screening of patients who have traveled to affected areas, he added. Those who do show symptoms should immediately be placed in isolation and will likely need treatment at a healthcare facility, he said.