Some time ago I wrote about Chagas (Break the Silence: Get the Word Out About Chagas). It recently turned up in the BBC News as a cause of stroke. Chagas disease is caused by a parasite passed on by a blood-sucking insect. The insect sucks your blood and leaves you a present—trypanosoma cruzi. This is one present you don't want.
If you get Chagas, your risk of stroke increases. Find out more by reading Parasite 'a growing stroke risk.'