Yellow Fever Kills 277, Infects 2,000+ in Angola: WHO

Yellow fever has killed 277 people in Angola and infected more than 2,000 others — and it's spread to other countries, too, the World Health Organization said Friday.

There's a global shortage of vaccine to protect people against the virus, which is a close cousin of Zika but much more deadly.

"The virus in Angola and Democratic Republic of Congo is largely concentrated in main cities and is likely to have been introduced to the cities following increased yellow fever viral circulation among monkeys in the forest," WHO said in a bulletin.

"There is a high risk of spread to neighboring countries."

Like its cousins Zika, chikungunya and dengue, yellow fever is spread by Aedes mosquitoes. But it kills 60,000 people a year. Up to half of those who get severely ill from yellow fever will die without intensive treatment.

There are no specific drugs to treat yellow fever, but good supportive care, such as giving fluids, can help patients survive.

"THERE IS A HIGH RISK OF SPREAD TO NEIGHBORING COUNTRIES."

WHO said the Democratic Republic of Congo had 38 cases of yellow fever exported from neighboring Angola, Kenya had two and one traveler had carried it to China.

"This highlights the risk of international spread through non-immunized travelers," WHO said.

Yellow fever vaccine is highly effective but it's mostly distributed by WHO, other U.N. agencies and non-profit groups such as GAVI. "The global supply of yellow fever vaccines has been insufficient for years," the Pan American Health Organization, WHO's Americas arm, says.

"The current outbreak in Angola has stretched existing yellow fever vaccine supplies."

Globally, around 80 million doses of yellow fever vaccine are made each year. But in parts of Africa, vaccination rates are below 50 percent.

Yellow fever also circulates in Latin America. This year so far, 20 cases have been reported in Peru, more than in many recent years. There were 21 cases in all of 2013 and the last time more than 20 cases were reported in a year was in 2007, when 29 cases were reported.

As in Africa, yellow fever infects monkeys so it remains a threat to people even with ongoing vaccination campaigns.