The viral haemorrhagic fever epidemic raging in Guinea is caused by several viruses which have similar symptoms—the deadliest and most feared of which is Ebola.
- The symptoms
Sudden onset of fever, with intense physical weakness, muscle pain, headaches and sore throat. This phase is often followed by vomiting, diarrhoea, rashes, kidney and liver failure and internal and external bleeding. The most serious cases are placed in intensive care and put on a drip to combat dehydration. No cure or vaccine is available, except for yellow fever. Ebola outbreaks have had mortality rates as high as 90 percent.
- The main viruses causing the fever
Four of the five known Ebola virus strains - Zaire, Sudan, Bundibugyo and Tai Forest - as well as Lassa, Marburg, Crimean-Congo and yellow fever, the best-known and oldest cause of hemorrhagic fever.
- Means of transmission
These viruses are spread by direct contact with blood, body fluids or tissues of the infected. However, some scientists suspect the possibility of contamination through the respiratory tract. Funeral rituals in which relatives and friends touch the body of the dead play an important role in transmission, as does handling dead or living animals carrying the virus.
- Viruses in Guinea
The Lassa virus is endemic throughout west Africa, and is present in Guinea alongside Ebola, but experts say yellow fever and Crimean-Congo are also likely culprits. The Ebola species detected in Guinea is Zaire, the most virulent.
This is the first Ebola outbreak among humans in west Africa. There was an epidemic of Tai Forest Ebola among chimpanzees in Ivory Coast in 1994, and a scientist who contracted the virus during an autopsy was treated in Europe without spreading it.
Experts have voiced astonishment that the Zaire strain—first observed in what is now Democratic Republic of Congo 38 years ago—has made the "substantial leap" to Guinea. Ebola outbreaks tend to be localised because, with the onset of symptoms occurring two to 21 days after infection, most victims have time to spread it too far before they are immobilised.
- Has the peak of the epidemic been reached?
Since the beginning of January, 78 people have died among 122 identified cases of haemorrhagic fever. Ebola has been detected in 22 samples from patients so far. The fever first appeared in southern Guinea, then spread to the centre of Guinea before showing up in the capital, Conakry.
Two cases of Ebola have been confirmed in Liberia from seven suspected cases and there are six suspected cases in Sierra Leone, none confirmed.
The World Health Organization (WHO), which coordinates the fight against the spread of epidemics, says the spread from southern Guinea has made predicting how the epidemic will play out impossible.
- Measures to prevent the spread
Aid agencies and Guinean health officials are focusing on prevention, education of at-risk populations on how to stay safe and isolation of patients. Experts say the quick identification of new samples is imperative, and mobile laboratories have been set up operational in Conakry and the southern town of Guekedou, according to the WHO.