ABOVE: Abidjan, Ivory Coast

Update (September 1):  The World Health Organization announced yesterday in a statement that a woman suspected of having Ebola virus in Ivory Coast had no evidence of the virus when samples were retested at the Pasteur Institute in Lyon, France. According to the statement, none of the woman’s contacts have tested positive or started displaying symptoms of the virus, and the WHO is now downgrading its containment efforts in Ivory Coast.  

Ivory Coast’s Ministry of Health and the World Health Organization announced Saturday (August 14) that the first case of Ebola virus had been detected in the country since 1994. According to the Associated Press, Health Minister Pierre N’Gou Demba says the virus was detected in an 18-year-old woman who had traveled by bus from Guinea to Abidjan, a major metropolitan center and the largest city in Ivory Coast (Cote d’Ivoire). She tested positive for Ebola the day after she arrived, and according to Demba, was diagnosed and treated immediately by medical professionals.

“It is of immense concern that this outbreak has been declared in Abidjan, a metropolis of more than 4 million people,” Matshidiso Moeti, the WHO’s regional director for Africa, says in a statement.

“However,” he adds, “much of the world’s expertise in tackling Ebola is here on the continent and Cote d’Ivoire can tap into this experience and bring the response to full speed.” After an outbreak of the disease began in Guinea in February, the WHO provided support to Ivory Coast and five other African nations to “beef up” their Ebola readiness, according according to Moeti, and “this quick diagnosis shows preparedness is paying off.” There was also an outbreak of Ebola in the Democratic Republic of Congo this year.

According to the statement, in response to the case the WHO is coordinating the transfer of 5,000 Ebola vaccines from Guinea to Ivory Coast to inoculate people at high risk for infection, including first responders, healthcare workers, and contacts of the confirmed case.

Additionally, the statement says local WHO staff will be supported by a “multidisciplinary team of WHO experts” who will help with things such as contact tracing, treatment, and infection prevention. Currently, WHO has issued no travel advisories to or from Ivory Coast.

This year’s Ebola outbreak in Guinea, which totaled 16 confirmed infections and 12 deaths, was officially declared over on June 19. According to the statement, officials will need to perform additional testing and genomic sequencing to determine whether there is a link between that outbreak and the newly detected case in Ivory Coast. According to the Associated Press, there is evidence that people can harbor infectious Ebola virus long after symptoms subside. Genomic analysis suggests that Guinea’s 2021 outbreak may have been caused by someone infected in the 2014–2016 epidemic, which spread to Sierra Leone and Liberia and killed 11,325 people.

Since that epidemic, two vaccines and new treatments have been developed, the AP reports. According to the WHO statement, if patients receive early treatment and supportive care, their odds of survival improve significantly compared with the 25 to 90 percent fatality rates seen in past outbreaks.

Ebola virus can be spread through contact with infected bodily fluids and tissues, says the WHO, and symptoms of Ebola—including muscle aches and fever—are similar to symptoms of other diseases including malaria and typhoid fever.

Earlier this month, Guinea announced its first known human case of Marburg virus, which is closely related to Ebola virus and has similar symptoms and fatality rates.