A research letter in this week’s issue of THE LANCET which describes a recent yellow fever outbreak in Guinea, Africa, highlights that there are insufficient stocks of yellow fever vaccine to cope with future outbreaks of the disease.
Yellow fever is a viral haemorrhagic fever that is caused by a flavivirus transmitted by mosquitoes. Case fatality ratios (CFR) exceed 50% in severe instances. The disease can be prevented by vaccination with the 17D yellow fever vaccine, which protects for at least 10 years. WHO estimates that 200 000 people in 34 endemo-epidemic countries of Africa and America are infected with the disease every year, resulting in 30 000 deaths.
Nicolas Nathan from Epicentre, Paris, France, and colleagues from the Guinean Department of Health describe a yellow fever epidemic that erupted in Guinea in September, 2000. A mass vaccination campaign was limited by insufficient international stocks. After the epidemic in Guinea, the International Coordinating Group on Vaccine Provision for Epidemic Meningitis Control decided that 2 million doses of 17D yellow fever vaccine, being stored as part of a UNICEF stockpile, should be used only in response to yellow fever outbreaks.
Nicolas Nathan comments: “Yellow fever epidemics are re-emerging in Africa and America, and the occurrence of repeated rural outbreaks increases the risk for major urban epidemics. However, as shown by the Guinean episode, the international stocks of yellow fever vaccines are not sufficient to provide an adequate and rapid response to large outbreaks. In 2000, an alert was sounded in Kano city (1.5 million inhabitants), Nigeria. No epidemic occurred, but had there been one the stocks of vaccines would not have been adequate. During the yellow fever consensus meeting, WHO recommended that an emergency stockpile of 1 million doses be retained in Africa and America for outbreak response.
Contact: Dr Nicolas Nathan, Epicentre, 75011 Paris, France; T) +33 1 40 21 28 48; f) +33 1 40 21 28 03; E) nnathan@epicentre.msf.org
The Lancet