Its important to point out that the Dengue cases detected in the city of Buenos Aires and the greater Buenos Aires areas are not native cases. This means that those that are infected have been traveling in the areas of the north of the country (mostly the borders with Paraguay and Brazil) and have been infected in those areas - they have not been infected in Buenos Aires.

The question must be asked as to why then are city officials fumigating....? Because there is a (slim, but it does exist) chance that native mosquitoes can pick up the virus from a migrant/traveler and then spread it locally......