WHO declares global health emergency for Ebola: What Americans should know

The World Health Organization declared a public health emergency of international concern over an outbreak of a rare Ebola virus in central Africa.

On May 17, WHO Director-General Tedros Adhanom Ghebreyesus announced the outbreak of the Bundibugyo virus, a species of Ebola, that has killed at least 80 people with nearly 250 suspected cases in eastern Democratic Republic of Congo as of May 16.

In neighboring Uganda, officials said laboratory results confirmed two cases in the capital of Kampala − including one death − among people traveling from Congo with no apparent link to each other. Another laboratory-confirmed case was also reported in Kinshasa, Congo's capital, infecting someone returning from the eastern Congolese province of Ituri where the outbreak is centered.

The WHO said the spread doesn't yet meet pandemic levels under international health regulations. Health experts told USA TODAY risk to Americans is low at this time.

The outbreak speaks to growing concerns among critics of the Trump administration around more limited global public health efforts. The United States, which withdrew from WHO under President Donald Trump, previously played a key role in surveilling emerging outbreaks.

“This is a serious and potentially devastating Ebola outbreak,” Dr. Tom Frieden, the former director of the U.S. Centers for Disease Control and Prevention during a major 2014 Ebola outbreak in West Africa, told USA TODAY in an emailed response. 

Frieden said that, by the time health workers detected this latest outbreak, cases have outnumbered those reported at the start of the 2014 Ebola epidemic in West Africa, which caused over 28,000 cases and 11,325 deaths over two years. Current insecurity in Congo, which faces civil unrest and armed conflict, makes control measures difficult, he noted.

“The world again faces grave risk and needs an urgent response,” Frieden said, alleging that the United States’ withdrawal from the WHO and other Trump administration actions have been “reckless.”

The Department of Health and Human Services did not immediately respond to USA TODAY's request for comment. The CDC has warned people traveling in the area should practice enhanced precautions.

The WHO said neighboring countries sharing land borders are considered at high risk for further spread because of travel and trade. Ebola spreads through bodily fluids from an infected person or contaminated objects, and animals can spread it to people, according to the CDC.

In a news conference on May 17, the CDC said it has activated its emergency response center. The agency said it's also coordinating with interagency partners and providing in-country support for surveillance and contact tracing, among other prevention measures. On the call, Dr. Satish Pillai declined to answer multiple questions from reporters asking whether any Americans have been exposed.

Pillai said individuals are at risk of transmitting the Bundibugyo virus when they're in contact with someone who is symptomatic. He added that identifying those infected, ensuring quarantine or isolation measures are taken, and providing supportive care are the most critical public health interventions right now.

Today, "risk to the American people is low," he added.

Where has the outbreak spread?

The outbreak has rapidly spread in a conflict zone in Congo’s border region since the Africa Centers for Disease Control and Prevention announced May 15 it was convening an urgent meeting with Congo, Uganda and South Sudan, along with global partners. The Bundibugyo virus is concerning compared with past outbreaks of the more commonly known Zaire virus because Bundibugyo has no vaccine or antiviral medication. 

However, Bundibugyo has a lower death rate in recent outbreaks, at around 32% in a 2007 Uganda outbreak, and at about 34% in Congo's 2012 outbreak, according to CDC estimates. Ebola was first identified in 1976 after a flare up in present-day Congo, which in decades since has had successive Ebola epidemics.

It’s not clear how quickly the latest Ebola outbreak is spreading, said Lina Moses, a Tulane University epidemiologist and disease ecologist who conducted contact tracing in Sierra Leone in the 2014 Ebola outbreak. Meanwhile, adequate lab testing is not in place, which may help explain why the Bundibugyo virus wasn’t identified earlier.

How Ebola spreads

A particular concern with Ebola is the timeline for when people show symptoms and become most infectious, according to Dr. Scott Roberts, associate medical director for infection prevention at Yale University's hospital. 

When disease symptoms present up to three weeks after contact with the virus, people experience a “dry” phase − marked by nondescript symptoms of fever, weakness and sore throat − that could be confused for influenza or malaria. 

After about four days, the “wet” phase begins as people become sicker. The symptoms include diarrhea, vomiting and unexplained bleeding. Roberts, an assistant professor at Yale School of Medicine, said this is when people become most contagious and when people might seek health care, putting hospital settings at risk for spread without adequate protections in place.

The current outbreak is already larger than the past two Bundibugyo surges, Roberts said.

“When you look at the scheme" of how Ebola spreads, he said, "this so far seems like it’s sort of a perfect storm of an outbreak."

(This story was updated to add new information.)

Contributing: Rachel Barber, USA TODAY

Eduardo Cuevas is based in New York City. Reach him by email at [email protected] or on Signal at emcuevas.01.