Macomb, IL – Even though Christmas is over for another year, blood collection agencies hope people are still in the mood to give. Jenny Garner of the Mississippi Valley Regional Blood Center says patients need blood every day of the year. But donations typically slow down during the summer months and again from Thanksgiving through mid-January. Garner says another challenge that's developed in recent years concerns who is allowed to give blood. She says blood collection agencies are coming across more potential donors who are either permanently or temporarily prohibited from giving. She says an example would be someone who was afflicted with West Nile virus. Garner says whenever a new infectious disease is identified, the blood center has to change its process for screening potential donors and testing blood.