"Streptomycin is the most effective antibiotic against Y. pestis and the drug of choice for treatment of plague, particularly the pneumonic form. Therapeutic effect may be expected with 30 mg/kg/day (up to a total of 2 g/day) in divided doses given intramuscularly, to be continued for a full course of 10 days of therapy or until 3 days after the temperature has returned to normal. Gentamicin has been found to be effective in animal studies, and is used to treat human plague patients."
Yes, the disease is treatable with antibiotics if administered early. However, the countries involved here are Third World, and historically inept in dealing with medical crises by themselves. You have to realize that they may not have sufficient amounts of the proper drugs, and, even if they do, they have to get them to the stricken people very quickly. So they will be on their hands and knees asking for international assistance - at least that’s the prediction.