Table 1. Sero-prevalence of tetanus antibody protection at enrollment.

	Days since tetanus toxoid vaccination
	0	14	28	42
	N (%)	N (%)	N (%)	N (%)
Total, N	620 (100)	237 (100)	213 (100)	147 (100)
Interpretation: Laboratory results
Insufficient immunity	354 (57.0)	17(7.3)	8 (3.8)	0
Need booster	153 (24.7)	18 (7.6)	9(4.2)	0
Booster needed 2–5 years	53 (8.5)	8 (3.4)	14 (6.6)	6 (4.1)
Booster needed 5–10 years	39(6.3)	35 (14.8)	44 (20.7)	38 (25.9)
Booster needed over 10 years	21 (3.4)	159 (67.1)	138 (64.8)	103 (70.1)