The critical blood shortage issued by the American Red Cross last week continues to affect the Tennessee Valley. Donors of all blood types are needed now and are asked to donate this Wednesday, Aug. 10.Many donors are busy or traveling, school is out of session, and donations in May and June dropped to the lowest levels the Red Cross has seen during this time frame in over a dozen years. Demand for blood remained steady during the same period, which is why the Red Cross needs people more than ever to roll up a sleeve and give as soon as possible.