The World Health Organization (WHO) has declared the spread of Ebola in West Africa an international health emergency.

WHO officials said the possible consequences were "particularly serious" because of the virulence of the virus.

The announcement came after experts convened a two-day emergency meeting in Switzerland. So far more than 930 people have died from Ebola in West Africa this year.

The United Nations health agency said the outbreak was an "extraordinary event". "A coordinated international response is deemed essential to stop and reverse the international spread of Ebola," it said in a statement.

The outbreak involves transmission in Guinea, Liberia, Nigeria and Sierra Leone.

The WHO said there would be no general ban on international travel or trade. However, states should be prepared to detect, investigate and manage Ebola cases, including at airports, it said.

Ebola virus disease (EVD)
• Symptoms include high fever, bleeding and central nervous system damage

• Fatality rate can reach 90% - but the current outbreak is about 55%

• Incubation period is two to 21 days

• There is no vaccine or cure

• Supportive care such as rehydrating patients who have diarrhoea and vomiting can help recovery

• Fruit bats are considered to be virus' natural host

In order to help our Embassy Community better understand some of the key points about the Ebola virus we have consulted with our medical specialists at the U S State Department and assembled this list of bullet points worded in plain language for easy comprehension. Our medical specialists remind everyone that they should be following the guideline from the center for Disease Control and the World Health Organisation.

• The suspected reservoirs for Ebola are fruit bats.

• Transmission to humans is thought to originate from infected bats or primates that have become infected by bats.

• Undercooked infected bat and primate (bush) meat transmits the virus to humans.

• Human to human transmission is only achieved by physical contact with a person who is acutely and gravely ill from the Ebola virus or their body fluids. Continue...

• Transmission among humans is almost exclusively among caregiver family members or health care workers tending to the very ill.

• The virus is easily killed by contact with soap, bleach, sunlight, or drying. A washing machine will kill the virus in clothing saturated with infected body fluids.

• A person can incubate the virus without symptoms for 2-21 days, the average being 5-8 days before becoming ill. THEY ARE NOT CONTAGIOUS until they are acutely ill.

• Only when ill does the viral load express itself first in the blood and then in other bodily fluids (to include vomit, feces, urine, breast milk, semen and sweat).

• If you are walking around you are not infectious to others.

• There are documented cases from Kikwit, DRC of an Ebola outbreak in a village that had the custom of children never touching an ill adult. Children living for days in small one room huts with parents who died from Ebola did not become infected.

• You cannot contract Ebola by handling money, buying local bread or swimming in a pool.

• There is no medical reason to stop flights, close borders, restrict travel or close embassies, businesses or schools.

• As always practice good hand washing techniques, but you will not contract Ebola if you do not touch a dying person.

• US EMBASSY