(CNN) An outbreak of Ebola in the Democratic Republic of Congo that began April 22 has resulted in at least one death and possibly two others, according to the World Health Organization.
The Congo Ministry of Health notified the WHO on Tuesday of nine suspected cases of Ebola illness and three deaths in the Likati health district within the northeastern province of Bas-Uele, which shares a border with the Central African Republic.
On Thursday, the Ministry of Health informed the WHO that of five samples, one tested positive for the Zaire strain of the Ebola virus at the National Institute of Biomedical Research laboratory in Kinshasa, the capital.
Additional laboratory samples are being tested. Six people remain hospitalized.
Officials suspect that the two other deaths were also caused by the highly infectious virus, which spreads through contact with bodily fluids, according to WHO spokesman Christian Lindmeier in Geneva.
Symptoms such as fever, headache, muscle pain, fatigue, diarrhea, vomiting, abdominal pain and hemorrhaging can begin two to 21 days after exposure.
The Zaire strain of the virus is one of the most lethal. A 2007 outbreak of this strain in Congo had a fatality rate of 74%, claiming 200 lives.
There is no approved vaccine to prevent the virus, and there is no approved treatment or cure. Clinical trials of an experimental vaccine are ongoing in West Africa.
"An investigation team led by the Ministry of Health and supported by WHO and partners has deployed and is expected to reach the affected area in the coming days," said Dr. Peter Salama, the WHO's executive director for health emergencies.
This is the eighth outbreak of Ebola that Congo has faced since 1976. The last epidemic began in August 2014 in the Boende region.
In 2014, more than 11,300 people were killed in the worst-ever outbreak of the virus in West Africa, most of them in Guinea, Sierra Leone and Liberia. During that outbreak, which was declared a "public health emergency of international concern" by the WHO, the Western Hemisphere also saw its first Ebola patients. Seven Americans who had been working in Africa became infected and were transported to the United States for treatment. In addition, two American nurses were infected after caring for a Liberian man who died from the virus in the hospital where they worked in Texas.
A team of first responders will be on site in Congo Friday or Saturday, including epidemiologists, biologists and specialists in the areas of social mobilization, risk communication, community engagement and water, hygiene and sanitation, said Dr. Allarangar Yokouidé, a WHO representative.
Dr. Matshidiso Moeti, regional director of WHO Africa, will arrive in Kinshasa this weekend for a meeting regarding the situation hosted by the Ministry of Health.
The US Centers for Disease Control and Prevention said it has not been called in to help. Médecins Sans Frontières, the United Nations Children's Fund (UNICEF) and other international organizations are standing by, ready to support the effort, according to WHO.
Bas-Uele province, with a population of 900,000 in 2007, is mostly inhabited by people of the Boa tribe, who live mainly through subsistence farming and hunting and conduct some trade by way of the Uele River.