To continue the long-term natural history of urinary tract infections in a cohort of girls who are now mostly in remission, found to have bacteriuria during school days by Dr. Calvin Kunin. To follow the incidence of bacteriuria in this cohort of girls to learn whether they continue to remain in remission or whether they eventually become infected. If they do become infected, to ascertain when, whether they will be symptomatic, and how the recurrences will be influenced during sexual activity, marriage and pregnancy. To compare the incidence and consequences of bacteriuria of this cohort of patients with a matched group of people derived from the same base population of school children and proven never to have had bacteriuria by the yearly screening studies of Dr. Kunin. To determine by routine urine cultures if the children of this group also have increased susceptibility to urinary tract infection. To continue to characterize the invading organisms to determine if the recurrences are due to reinfections as opposed to relapse or partial suppression. To determine the incidence of hypertension in these groups. To continue to evaluate the therapeutic program of short-term therapy combined with frequent followup examination, with the use of significant bacteriuria as the end point, as outlined by Dr. Kunin.