The Director-General of WHO, Dr Margaret Chan, arrived today in Angola’s capital Luanda for a two-day visit to assess the situation of the current outbreak of yellow fever virus.

Since December 2015, Angola has been grappling with a yellow fever outbreak, which has infected more than 490 people and killed 198. The outbreak, which was first reported in the capital city Luanda, has since spread to 6 of the country’s 18 provinces.

“This is the most serious outbreak of yellow fever that Angola has faced in 30 years,” says Dr Chan, who visited a vaccination point in Luanda. “WHO is taking urgent action to support the Government to control this outbreak with a widespread vaccination campaign.”

Yellow fever virus is transmitted by infected mosquitoes, the most common species being Aedes aegypti – the same mosquito that spreads the Zika virus. Symptoms include fever, headache, muscle pain, nausea, vomiting and fatigue. A small percentage of infected people experience a second, more severe phase of illness which includes high fever, jaundice and internal bleeding. At least half of severely affected patients who don’t receive treatment die within 10 to 14 days.