The World Health Organization’s emergency committee is holding talks to discuss the Ebola epidemic.
The meeting in Geneva is examining screening measures at borders and considering whether stricter travel regulations should be put in place.
New rules in the US require travellers from the worst affected countries to arrive at one of five airports.
The known death toll is now 4,877 – a rise of 322 since the WHO’s last report five days ago.
Most of the victims died in Guinea, Liberia and Sierra Leone.
Meanwhile, first batches of an experimental vaccine against Ebola are due to arrive to Switzerland.
The vaccine, developed by Canada’s public health agency, combines fragments of Ebola with a non-fatal virus and could trigger the immune system to produce the necessary antibodies.However, the BBC’s Imogen Foulkes in Geneva says a fully tested and approved vaccine is not expected to become available for months or possibly years.
In Sierra Leone, a curfew has been imposed in a town after two people were shot dead in riots linked to the Ebola outbreak.
The riots in Koidu on Tuesday were sparked by attempts to place an elderly woman – said to be 90 years old – under quarantine.
The woman has since died but it is not clear whether she actually had Ebola, the BBC’s Umaru Fofana reports from the capital, Freetown.
In other developments
- An opposition MP in Guinea has revealed a photocopy of a report by scientists from the 1980s that challenges the assumption that Ebola is new to West Africa. The study carried out by those working at Guinea’s respected Pasteur Institute blames the virus for the deaths of 137 people in a remote area in 1982
- NBC freelance cameraman Ashoka Mukpo – who contracted Ebola in West Africa – has been declared free of the virus and will leave hospital in the US state of Nebraska on Wednesday
- UK International Development Secretary Justine Greening is in Sierra Leone to assess the impact of the government’s $200m (£125m) aid package
- Doctors in Spain said a second round of tests showed Teresa Romero, who became the first person to contract Ebola outside West Africa, was completely clear of the virus. The nurse fell ill after treating two infected patients in a Madrid hospital
- A Cuban medical team has arrived in Liberia to join the fight against Ebola.
The WHO’s emergency committee is meeting to discuss Ebola for the third time with the aim of assessing the efforts so far to contain and control the virus.
The world health body has faced criticism that it reacted too slowly to the spread of the disease.
New rules came into force in the US requiring air passengers from Sierra Leone, Liberia and Guinea to travel via O’Hare in Chicago, JFK, Newark, Washington’s Dulles or Atlanta airports, where they will undergo enhanced screening.
Elhadj As Sy, secretary general of the International Federation of the Red Cross, described calls for travel bans to contain the epidemic as “irrational” as it created panic and isolated affected countries.