The Hantavirus has an incubation period from 1 to 4 weeks.
So if you've been exposed to the Hantavirus you can expect to get the symptoms as early as 1 week or even sometimes 6 weeks later.
When you do have the Hantavirus you'll have symptoms that seem like the flu and other illnesses including Headaches and Fevers as well as myalgias.
If you do have the Hantavirus you should go seek medical attention as it can be deadly if not treated.