Smallpox produced the death of up to thirty percent of those infected, so Jenner's preventive method spread quickly. The Spanish government designed and supported a ten-year effort to carry smallpox vaccine to its American and Asian territories in a chain of arm-to-arm vaccination of children. An expedition directed by Doctor Francisco Xavier de Balmis sailed from Corunna in November 1803, stopping in the Canary Islands, Puerto Rico, and Venezuela. Balmis led a subexpedition to Cuba, Mexico, and the Philippines; his assistants returned to Mexico in 1807, while Balmis took vaccine to China and returned to Spain (and again to Mexico, 1810–13). Vice-director José Salvany and his staff took vaccine to present-day Colombia, Ecuador, Peru, Bolivia, and Chilean Patagonia. The Spanish Royal Philanthropic Vaccine Expedition shows the first attempts to solve questions still important for the introduction of new immunizations—professionalization in public health, technology transfer, protection of research subjects, and evaluation of vaccine efficacy, safety, and cost.