Update May 10
The World Health Organization said on Wednesday, May 10, that it was informed two days previously by the Ministry of Health of Liberia that samples from four deceased people had tested positive for meningitis C (Neisseria menigitidis).
WHO said that, although this points to meningitis as the probable cause, “the investigation is still ongoing to determine if this bacteria is responsible for other reported illnesses in this cluster.”
Since May 5, one further person has died, bringing the total to 13, and three additional cases have been reported.
The World Health Organization said on Friday, May 5 that 12 people have died in Liberia from an unexplained illness over the previous two weeks.
The unexplained deaths initially raised fears that Ebola may have returned to the country, less than a year after WHO declared Liberia free of transmission. The 2013 outbreak killed more than 11,300 people, mostly in Liberia, Guinea and Sierra Leone.
— Tanu Jalloh (@jalloh_tanu) April 26, 2017
But WHO said 21 specimens have tested negative for both Ebola virus disease and Lassa fever. Additional samples were sent to the United States and the WHO Reference Laboratory in South Africa for analysis.
Preliminary test results from water sources serving the affected areas also ruled out bacterial contamination.
On April 25, the Ministry of Health of Liberia notified WHO of a cluster of sudden deaths in Sinoe County. The event began two days earlier when an 11-year-old girl was admitted to the Francis J. Grante Hospital in Greenville with diarrhea, vomiting and mental confusion. She died within an hour.
As of May 4, a total of 28 cases were reported in Sinoe County and Montserrado County. Ten people in Sinoe and two in Montserrado have died, a fatality rate of 43 percent. WHO says most of the people who died are under the age of 21.
All 26 cases in Sinoe County and one case in the capital Monrovia, Montserrado County, were people who attended the April 22 funeral of a religious leader in Greenville.
In the Monrovia case, a man who attended the funeral presented on April 27 and died in hospital. His partner did not attend the funeral but became ill and died on April 29.
Low risk of spread
WHO said it believes the risk of the illness spreading is low, because the cases are clustered among people who attended the funeral, and the number of cases and deaths reported since April 25 has decreased sharply.
Forty-two people in Montserrado County who attended the funeral are being monitored, along with others who are close contacts of the couple who died.
The Liberian government requested toxicological testing at labs outside the country, and WHO says it is actively investigating the possibility of food, drink or water contamination.
The 2014 Ebola outbreak hit Liberia hard, killing an estimated 4,809 people and infecting more than 10,600 others.
Liberia was first declared free of Ebola in May 2015 but a flare-up was reported seven weeks later. The country was finally declared Ebola-free on June 9, 2016.
The country is now working to expand access to mental health care for Ebola survivors, who are also likely suffer chronic pain and other lingering physical ailments, according to Médecins Sans Frontières. MSF found that over one-fifth of Ebola survivors in Sierra Leone were at high risk of developing PTSD.
WHO says Ebola vaccine trials of 11,000 people in Guinea resulted in a vaccine that is highly protective against the virus.