In the 1980s, outbreaks in Tanzania and Kenya were controlled by the use of 26 million doses of vaccine, and a recurrence of the disease in 1997 was suppressed by an intensive vaccination campaign.
1980-ndatel ohjati Tansaania ja Keenia puhanguid 26 miljoni vaktsiinidoosi abil ja 1997. aastal korraldati haiguse taasilmumise korral selle allasurumiseks ulatuslik vaktsineerimiskampaania.