Argentines are sticklers for fumigation and men in white coats make regular house visits to spray into those dark corners. In Buenos Aires, they’re usually after ants and cockroaches, which are quite a problem in the summer. South America’s really nasty creepy crawlies don’t make it as far south as Buenos Aires or Patagonia.
Further north, however, where it’s hotter, and especially in low-lying tropical areas, it’s advisable to take malaria pills. Obviously the best approach is to avoid being bitten by mosquito’s altogether. Dengue fever, which is prevalent in some areas, is also transmitted by mosquitoes. Other dangers in the north include leishmaniasis and Chagas’ disease. Chagas’ disease is transmitted through the bite of the vinchuca beetle, causing arteries to harden and long-term complications that eventually lead to death. The beetle likes adobe buildings with dirt floors and decrepit roofs and usually comes out at night, so avoid sleeping in such dwellings if you can. If you have no choice, tuck up your feet (the beetles go for these) and use a mosquito net. If you think you’ve been bitten by a vinchuca, seek medical advice immediately. If you’ve been in a malarial area and show symptoms even as late as a year after your trip, see a doctor immediately.