An outbreak of yellow fever in Angola in which hundreds have already died could be "a threat to the entire world", the World Health Organisation has warned.
Cases of the mosquito-borne virus were first reported in Angola's capital Luanda in December. The disease has now spread to 16 of the country's 18 provinces.
So far, thousands of people are suspected to have been infected with the disease and 238 people have died, WHO has reported.
"The evolution of the situation in Angola is concerning and needs to be closely monitored," it stated in a report.
People travelling from Angola have already exported the virus to China, Kenya and the Democratic Republic of Congo, where at least 21 people are reported to have died.
The trend has sparked concerns among the WHO, which fears the virus is at risk of spreading further because of the large international communities living in Angola that regularly travels to neighbouring countries.
Countries where there are Aedes mosquitos, carriers of the yellow fever virus, are particularly at risk. Areas where there have been previous outbreaks of Dengue, Chikungunya or Zika virus would also be fertile grounds for the disease to spread.
WHO has called for "an urgent need to strengthen the quality of the response in Angola" and increase the control of travellers' immunisation status, when coming from areas affected by the virus.
Together with UNICEF, the Centers for Disease Control and Prevention and Médecins Sans Frontières (MSF), WHO is monitoring the situation in Angola and a situation of emergency has been declared.
No travel or trade restrictions to Angola have yet been advised.
