'The global transfer of diseases became instrumental

‘The global transfer of diseases became instrumental in colonisation of Africa and South America’. Explain the statement.

This statement states the fact that the European conquest of colonies in Africa as well as South America was not just a result of superior, modern, sophisticated firepower but because of the germs such as those of smallpox that they carried with them. Smallpox in particular proved to be a fatal disease. Once it reached the continent, it started spreading deep into the condnent and also before reaching any European there.