It appears that recent flooding in Nicaragua has caused an increase in reported/diagnosed cases of leptospirosis. Managua and the cities of Chinandega and Puerto Sandino appear to be the hardest hit. If you are headed to the area or already there, make sure to be on the look out for symptoms and try to minimize contact with standing water.
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For those who may be looking, good medical information concerning leptospirosis can be found here.