Aid workers and health officials battled Monday to contain west Africa's first outbreak of the deadly Ebola virus as tests on suspected cases in Conakry allayed fears that it had spread to the Guinean capital.
At least 59 people have died in an outbreak of the virulent virus raging through Guinea's southern forests but tests on three haemorrhagic fever cases—two of them fatal—in Conakry were negative, the government said.
"The Pasteur Institute in Dakar worked urgently all last night on samples taken from suspected cases here in Conakry, which were all negative," said Sakoba Keita, the health ministry's chief disease prevention officer.
"So for now, there's no Ebola in Conakry, but haemorrhagic fever whose nature remains to be determined."
The UN Children's Fund (UNICEF) said in a statement on Sunday the Ebola virus had quickly spread from the south to Conakry.
Keita said however that the Pasteur Institute was still working on identifying the virus behind the fever cases in the capital and would know more "in the coming hours".
"The total suspect cases recorded to date, amount to 86 cases with 59 deaths," the health ministry said in a statement, indicating that most cases reported since the start of the outbreak in early February were in the south.
The first analyses of samples conducted by the Pasteur Institute in the French city of Lyon showed that cases in southern Guinea were due to the Ebola virus.
To date, no treatment or vaccine is available for the pathogen, which kills between 25 and 90 percent of those who fall sick, depending on the strain of the virus, according to the WHO.
The disease, one of the world's most virulent, is transmitted by direct contact with blood, faeces or sweat, or by sexual contact and the unprotected handling of contaminated corpses.
The tropical virus—described in some health publications as a "molecular shark"—can fell its victims within days, causing severe fever and muscle pain, weakness, vomiting and diarrhoea—in some cases shutting down organs and causing unstoppable bleeding.
It was first discovered in the Democratic Republic of Congo (DRC) in 1976. The central African country has suffered eight outbreaks.
The most recent epidemic, also in the DRC, infected 62 people and left 34 dead between May and November 2012, according to the country's health ministry.
Although there have also been outbreaks among humans in Uganda, the Republic of Congo and Gabon, the disease had never before been detected in people in west Africa.
According to researchers, the virus multiplies quickly, overwhelming the immune system's ability to fight the infection.
Aid organisation Plan International warned that the epidemic risked spreading to neighbouring countries because of the free movement of people across borders.
"Communities, especially children, in the border areas between Guinea, Liberia and Sierra Leone are vulnerable and need immediate support," Ibrahima Toure, Plan's country director in Guinea, said in a statement.
Guinea's health ministry said it was offering free treatment in isolation centres and raising awareness through all the media of good hygiene.
Doctors Without Borders (MSF) and WHO teams already on the ground are distributing sanitation kits and protective equipment while tracking those who have been in contact with the infected.
Meanwhile, experts in haemorrhagic fevers were expected from Dakar and Lyon to help in the quick identification of further samples.
No neighbouring country has reported an outbreak but Senegal, Sierra Leone and Ivory Coast have reactivated their epidemiological surveillance systems while the French embassy in Liberia has warned its nationals to avoid travel to southern Guinea.
Sierra Leonean aid organisation the Health For All Coalition warned that "the tendency of its transmission remains high" in border areas.
"People, goods and animals—such as sheep, goats and cows used in Sierra Leone—come from Guinea and it is these districts that they are brought into. And in these areas, people hunt for birds, monkeys and baboons for food."
The country's chief medical officer Brima Kargbo warned against contact with birds as well as terrestrial animals but added that there was "no cause for alarm as no case has been diagnosed".
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