Yellow Fever Outbreak Puts Pressure on Global Vaccine Supply

Officials in the Democratic Republic of Congo (DRC) declared an epidemic of yellow fever in three regions on Monday. The announcement comes amid an outbreak that is rapidly using up the global stockpile of vaccines for the mosquito-borne disease.

The outbreak was first identified in Angola in late December 2015, and so far that country has reported more than 3,100 cases. The DRC has reported more than 1,000 suspected cases, and Kenya and China have also reported cases of the disease imported by travelers. Most people infected with yellow fever have mild or no symptoms, but some experience fever, chills, aching, nausea and fatigue. In some cases, the disease can lead to organ failure.

Other countries, including Brazil, Chad, Colombia, Ethiopia, Ghana, Peru and Uganda are also reporting outbreaks of yellow fever that appear to be unrelated to the outbreak that started in Angola.

The World Health Organization (WHO) has not declared the outbreak a public health emergency but is concerned about a possible shortage of vaccines to prevent the disease. The agency reports that the global stockpile of 6 million vaccines for emergencies has been replenished twice already this year, despite the fact that the amount is usually enough to last a whole year. “This has never happened before,” the agency said in a statement. As a response, the agency concluded that one fifth of the regular dosage for the yellow fever vaccine could be used during emergency shortages.

“Right now we have enough vaccines in the global stockpile to cope with the ongoing outbreaks if there are no further extensions,”said Jon Abramson, chair of the WHO Strategic Advisory Group of Experts on Immunization, in a statement on June 17. “However, given the wide spread of the disease in Angola and the potential for it to get out of control in the city of Kinshasa, in the Democratic Republic of Congo, WHO and partners are seriously considering the use of this dose-sparing strategy to prevent transmission through large-scale vaccination campaigns.”

Close to 18 million doses of the vaccine have been distributed in Angola, the DRC and Uganda. “In the face of increasing demands this year, the four major manufacturers who supply the global stockpile of the yellow fever vaccine have been working around the clock to replenish the stockpile,” the WHO says.