A mystery disease has killed at least eight people in Liberia since Monday, the deaths occurring in the Sinoe county, some 350 km (217 miles) from Monrovia, the capital.
The health ministry is testing blood samples of those who died with results expected this week, Reuters reported.
The World Health Organization (WHO) received a report from Liberian health authorities about the unexplained illness, and said the country’s health authorities were taking immediate precautionary measures to prevent further contagion.
“According to this report, since Monday 14 people have fallen sick. Eight people have died and six are seriously ill and still in the hospital. Health authorities are taking immediate precautionary measures such as isolating suspect cases, tracing contacts and engaging with the community and their leaders," WHO told Reuters.
According to an internal UN memo quoted by the BBC, seven people died on Tuesday morning and the deaths were linked to a case of an 11-year-old girl who had symptoms of "diarrhoea, vomiting and mental confusion".
The unknown disease has hit Liberia ten months after nearly 5,000 people died due to the outbreak of a hemorrhagic fever, known as Ebola, in the African nation.
Liberian authorities, however, rule out a possible return of Ebola to the country.
"Initial testing conducted by the Liberian Institute of Biomedical Research in Charlesville, Margibi County, has ruled out the Ebola virus disease as the cause of the deaths," the Chief Medical Officer of Liberia, Dr. Francis Kateh, told a news conference in Monrovia on Wednesday, according to Reuters.
Kateh also told the BBC’s Focus on Africa that further investigations were necessary to identify the disease. "We are worried... we are all having sleepless nights to make sure we find what is causing the deaths,"he said.
Liberia was one of the three West African countries – along with Sierra Leone and Guinea – worst affected by an Ebola outbreak that began in 2014. At least 11,310 people died and 28,600 were infected.
WHO declared Liberia Ebola-free in June 2016, officially ending the outbreak in West Africa. Sierra Leone was declared free from the virus on November 7, 2015, while Guinea was given the status on December 29.
However, Liberia had twice been declared free from Ebola, in May and September 2015, only for new cases of infection to emerge.
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