General information about the blood donor eligibility can be found in the Donor Eligibilty section 

Post Donation: If you recently donated and have developed a fever or other symptoms that suggest a recent infection or you want to provide additional information about your donation please call 1-866-236-3276 for immediate assistance (Option 2 in the phone system). For your convenience, this number is available 24 hours a day, 365 days a year.